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Evaluation of performance improvements following either resistance training or sprint interval based concurrent training
Abstract
The purpose of this investigation was to examine the effects of concurrent sprint interval and resistance training (CST) vs. resistance training (RT) on measures of strength, power, and aerobic fitness in recreationally active females. Twenty-eight females (20.3 ± 1.7 years; 63.0 ± 9.1; 51.1 ± 7.1 one repetition max back squat (kg); 35.4 ± 4.1 ml·kg·min VO2max) were recruited to complete an 11-week training program. Participants were matched-pair assigned to CST or RT cohorts following preliminary testing which consisted of 1 repetition max back squat, maximal isometric squat, anaerobic power evaluations, and maximal oxygen consumption. All subjects trained 3 d⋅wk with sprint interval training occurring at least 4 h following resistance training in the CST cohort. Both CST and RT resulted in significant improvements (p < 0.05) in one repetition max back squat (37.5 ± 7.8; 40.0 ± 9.6 kg), maximal isometric force (55.7 ± 51.3; 53.7 ± 36.7 kg), average peak anaerobic power testing (7.4 ± 6.2; 7.6 ± 6.4 %), and zero incline treadmill velocity resulting in maximal oxygen consumption (1.8 ± 0.6; 0.8 ± 0.6 km⋅h) . Only zero incline treadmill velocity demonstrated a group by time interaction with a greater improvement following CST (p < 0.01). Rate of force development was not altered in either group. Results provide no evidence of interference to the adaptive process by CST. Coaches desiring improvements in strength, power, and endurance may want to evaluate how sprint / high intensity interval training might supplement programs already in place.
... To calculate the ES in CMA, pre-and post-training data for each group (mean, SD, and N) were used. In five of the included studies, the mean and SD were extracted manually from graphs [3,4,6,14,38]. Funnel plots stratified by training status were used to quantify potential publication bias. ...
... A total of 750 participants were included (523 men and 227 women), aged 20-38 years. Seven studies involved untrained individuals [11][12][13][14][21][22][23], 10 studies involved moderately trained individuals [3,5,10,15,16,[38][39][40][41]45], and 10 studies involved trained individuals [4,6,8,24,25,35,36,[42][43][44]. The corresponding authors of 16 studies were contacted [3-6, 14-16, 21, 22, 25, 36, 38-42] for clarification or missing information via e-mail, of whom five responded with additional information [5,15,16,36,39]. ...
... Of the studies, 12 performed concurrent resistance and endurance training within the same session (< 20 min between sessions) [4,5,13,14,16,21,23,25,36,40,43,45], 13 performed concurrent resistance and endurance trainings during different sessions (> 2 h between sessions) [3, 6, 10-12, 15, 24, 25, 35, 38, 39, 41, 44], two of the studies mixed performing concurrent resistance and endurance training during the same and different sessions during the training programme [8,22], and one study did not report whether the trainings were performed in the same or different sessions [42]. With regard to the outcome variables, 15 of the studies measured the maximal dynamic strength with leg press exercise (and two of these also measured squat exercise) [5, 6, 10-13, 15, 16, 21, 23, 24, 39-41, 45], and 14 with squat exercise [3,4,8,14,22,24,25,35,36,38,40,[42][43][44]]. ...
Background
The effect of concurrent training on the development of maximal strength is unclear, especially in individuals with different training statuses.
Objective
The aim of this systematic review and meta-analysis study was to compare the effect of concurrent resistance and endurance training with that of resistance training only on the development of maximal dynamic strength in untrained, moderately trained, and trained individuals.
Methods
On the basis of the predetermined criteria, 27 studies that compared effects between concurrent and resistance training only on lower-body 1-repetition maximum (1RM) strength were included. The effect size (ES), calculated as the standardised difference in mean, was extracted from each study, pooled, and analysed with a random-effects model.
Results
The 1RM for leg press and squat exercises was negatively affected by concurrent training in trained individuals (ES = – 0.35, p < 0.01), but not in moderately trained ( – 0.20, p = 0.08) or untrained individuals (ES = 0.03, p = 0.87) as compared to resistance training only. A subgroup analysis revealed that the negative effect observed in trained individuals occurred only when resistance and endurance training were conducted within the same training session (ES same session = – 0.66, p < 0.01 vs. ES different sessions = – 0.10, p = 0.55).
Conclusion
This study demonstrated the novel and quantifiable effects of training status on lower-body strength development and shows that the addition of endurance training to a resistance training programme may have a negative impact on lower-body strength development in trained, but not in moderately trained or untrained individuals. This impairment seems to be more pronounced when training is performed within the same session than in different sessions. Trained individuals should therefore consider separating endurance from resistance training during periods where the development of dynamic maximal strength is prioritised.
... The equivocal results were possibly due to methodological issues, such as differences in training volume and duration, muscle mass assessment (i.e., whole muscle vs muscle fiber cross-sectional area), and small sample sizes [31,33,34,37,38]. Recently, additional studies have investigated the effect of HIIT-based CT models on muscle strength and mass [3,8,11,16,19,21,[39][40][41][42][43][44][45][46][47]. Interestingly, data suggest that HIIT-based CT protocols (i.e., RST and SIT) impair neither muscle strength nor muscle mass gains compared to RT alone [11,[40][41][42][43][44]. ...
... Recently, additional studies have investigated the effect of HIIT-based CT models on muscle strength and mass [3,8,11,16,19,21,[39][40][41][42][43][44][45][46][47]. Interestingly, data suggest that HIIT-based CT protocols (i.e., RST and SIT) impair neither muscle strength nor muscle mass gains compared to RT alone [11,[40][41][42][43][44]. These results are exciting due to the potential practical application of those CT protocols in sport and health contexts. ...
... Other studies have compared the gains in muscle mass between HIIT-based CT protocols and RT alone protocols [8,19,22,[39][40][41][42]. As evidence suggests that HIIT protocols can increase [35,36,59] or have no effect [31,33,37,38] on muscle mass, it is reasonable to suggest that HIIT-based CT models could preclude the occurrence of the interference effect on muscle mass. ...
Previous research has suggested that concurrent training (CT) may attenuate resistance training (RT)-induced gains in muscle strength and mass, i.e.‚ the interference effect. In 2000, a seminal theoretical model indicated that the interference effect should occur when high-intensity interval training (HIIT) (repeated bouts at 95–100% of the aerobic power) and RT (multiple sets at ~ 10 repetition maximum;10 RM) were performed in the same training routine. However, there was a paucity of data regarding the likelihood of other HIIT-based CT protocols to induce the interference effect at the time. Thus, based on current HIIT-based CT literature and HIIT nomenclature and framework, the present manuscript updates the theoretical model of the interference phenomenon previously proposed. We suggest that very intense HIIT protocols [i.e., resisted sprint training (RST), and sprint interval training (SIT)] can greatly minimize the odds of occurring the interference effect on muscle strength and mass. Thus, very intensive HIIT protocols should be implemented when performing CT to avoid the interference effect. Long and short HIIT-based CT protocols may induce the interference effect on muscle strength when HIIT bout is performed before RT with no rest interval between them.
... Thus, it is reasonable to assume that the neuromuscular effects of very short efforts (i.e. 5 s) in a CT program could minimize the interference phenomenon, given that they provoke less metabolic disturbances and residual fatigue (Balsom et al. 1992a;Benitez-Flores et al. 2018). In addition, to the best of our knowledge, there are no data on the potential benefits of CT methods integrating shorter SIT for cardiometabolic health, as previous studies have mainly focused on neuromuscular adaptations (Cantrell et al. 2014;Laird et al. 2016). Such findings would improve our understanding of the benefit that SIT protocols may have on aerobic and anaerobic performance development, as well as cardiometabolic health-related parameters. ...
... In this regard, concomitantly training very short duration sprinting and resistance exercise bouts might promote a lower interference effect as they produce similar neuromuscular demands (Wilson et al. 2012). For instance, two previous studies reported that modified SIT of 20 s did not impair the gains in maximum strength of upper and lower limbs (Cantrell et al. 2014;Laird et al. 2016). The current findings are in line with these previous studies (Cantrell et al. 2014;Laird et al. 2016), as CTG improved power and force in the squat exercise to a similar extent than RESG. ...
... For instance, two previous studies reported that modified SIT of 20 s did not impair the gains in maximum strength of upper and lower limbs (Cantrell et al. 2014;Laird et al. 2016). The current findings are in line with these previous studies (Cantrell et al. 2014;Laird et al. 2016), as CTG improved power and force in the squat exercise to a similar extent than RESG. Furthermore, the present study demonstrated that performing cycling training prior to strength training did not impede on lower body strength development as previously reported (Eddens et al. 2017;Sabag et al. 2018). ...
Purpose
The aim of this study was to compare the combined effects of resistance and sprint training, with very short efforts (5 s), on aerobic and anaerobic performances, and cardiometabolic health-related parameters in young healthy adults.
Methods
Thirty young physically active individuals were randomly allocated into four groups: resistance training (RTG), sprint interval training (SITG), concurrent training (CTG), and control (CONG). Participants trained 3 days/week for 2 weeks in the high-intensity interventions that consisted of 6–12 “all out” efforts of 5 s separated by 24 s of recovery, totalizing ~ 13 min per session, with 48–72 h of recovery between sessions. Body composition, vertical jump, lower body strength, aerobic and anaerobic performances, heart rate variability (HRV), and redox status were evaluated before and after training. Total work (TW), rating of perceived exertion (CR-10 RPE) and mean HR (HRmean) were monitored during sessions. Incidental physical activity (PA), dietary intake and perceived stress were also controlled.
Results
Maximum oxygen consumption (VO2max) significantly increased in SITG and CTG (P < 0.05). Lower body strength improved in RTG and CTG (P < 0.05), while countermovement jump (CMJ) was improved in RTG (P = 0.04) only. Redox status improved after all interventions (P < 0.05). No differences were found in TW, PA, dietary intake, and psychological stress between groups (P > 0.05).
Conclusions
RT and SIT protocols with very short “all out” efforts, either performed in isolation, or combined, demonstrated improvement in several physical fitness- and health-related parameters. However, CT was the most efficient exercise intervention with improvement observed in the majority of the parameters.
... Multiple studies have assessed whether HIIT and RT can be trained concurrently without compromising the training outcomes (Balabinis, Psarakis, Moukas, Vassiliou, & Behrakis, 2003;de Souza et al., 2013;Fyfe, Bartlett, Hanson, Stepto, & Bishop, 2016;Gentil et al., 2017;Kikuchi, Yoshida, Okuyama, & Nakazato, 2016;Robineau, Babault, Piscione, Lacome, & Bigard, 2016;Robineau, Lacome, Piscione, Bigard, & Babault, 2017;Ross et al., 2009;Wilson et al., 2012). However, the results vary with some studies showing that HIIT does not impede strength development and hypertrophy (Cantrell, Schilling, Paquette, & Murlasits, 2014;de Souza et al., 2013;Laird et al., 2016), whilst others studies have reported contrary findings (Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016). ...
... The database search yielded 6036 potential studies ( Figure 1). Fourteen studies (Balabinis et al., 2003;Cantrell et al., 2014;de Souza et al., 2013;Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016;Laird et al., 2016;Leveritt, Abernethy, Barry, & Logan, 2003;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009;Sale, Jacobs, MacDougall, & Garner, 1990;Silva et al., 2012;Tsitkanou et al., 2016) met the eligibility criteria and were included in the systematic review and meta-analysis. Only 1 study (Gentil et al., 2017) was excluded from the meta-analysis for displaying a p score of <0.05 using Kendall's τ statistic. ...
... A summary of the intervention characteristics including the HIIT and RT frequency, volume, and intensity are displayed in Table 2. Seven of 14 studies performed cycling HIIT (Cantrell et al., 2014;Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016;Leveritt et al., 2003;Sale et al., 1990;Tsitkanou et al., 2016), whilst the remaining 7 studies performed running HIIT (Balabinis et al., 2003;de Souza et al., 2013;Laird et al., 2016;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009;Silva et al., 2012). Eight of the 14 studies (Balabinis et al., 2003;Cantrell et al., 2014;Gentil et al., 2017;Kikuchi et al., 2016;Laird et al., 2016;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009) performed sprintinterval or a variation of supramaximal training whilst the remaining 6 studies (de Souza et al., 2013;Fyfe et al., 2016;Leveritt et al., 2003;Sale et al., 1990;Silva et al., 2012;Tsitkanou et al., 2016) performed a variation of HIIT with peak workload intervals reaching but not exceeding 100% VO2max. ...
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... Multiple studies have assessed whether HIIT and RT can be trained concurrently without compromising the training outcomes (Balabinis, Psarakis, Moukas, Vassiliou, & Behrakis, 2003;de Souza et al., 2013;Fyfe, Bartlett, Hanson, Stepto, & Bishop, 2016;Gentil et al., 2017;Kikuchi, Yoshida, Okuyama, & Nakazato, 2016;Robineau, Babault, Piscione, Lacome, & Bigard, 2016;Robineau, Lacome, Piscione, Bigard, & Babault, 2017;Ross et al., 2009;Wilson et al., 2012). However, the results vary with some studies showing that HIIT does not impede strength development and hypertrophy (Cantrell, Schilling, Paquette, & Murlasits, 2014;de Souza et al., 2013;Laird et al., 2016), whilst others studies have reported contrary findings (Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016). ...
... The database search yielded 6036 potential studies ( Figure 1). Fourteen studies (Balabinis et al., 2003;Cantrell et al., 2014;de Souza et al., 2013;Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016;Laird et al., 2016;Leveritt, Abernethy, Barry, & Logan, 2003;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009;Sale, Jacobs, MacDougall, & Garner, 1990;Silva et al., 2012;Tsitkanou et al., 2016) met the eligibility criteria and were included in the systematic review and meta-analysis. Only 1 study (Gentil et al., 2017) was excluded from the meta-analysis for displaying a p score of <0.05 using Kendall's τ statistic. ...
... A summary of the intervention characteristics including the HIIT and RT frequency, volume, and intensity are displayed in Table 2. Seven of 14 studies performed cycling HIIT (Cantrell et al., 2014;Fyfe et al., 2016;Gentil et al., 2017;Kikuchi et al., 2016;Leveritt et al., 2003;Sale et al., 1990;Tsitkanou et al., 2016), whilst the remaining 7 studies performed running HIIT (Balabinis et al., 2003;de Souza et al., 2013;Laird et al., 2016;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009;Silva et al., 2012). Eight of the 14 studies (Balabinis et al., 2003;Cantrell et al., 2014;Gentil et al., 2017;Kikuchi et al., 2016;Laird et al., 2016;Robineau et al., 2016Robineau et al., , 2017Ross et al., 2009) performed sprintinterval or a variation of supramaximal training whilst the remaining 6 studies (de Souza et al., 2013;Fyfe et al., 2016;Leveritt et al., 2003;Sale et al., 1990;Silva et al., 2012;Tsitkanou et al., 2016) performed a variation of HIIT with peak workload intervals reaching but not exceeding 100% VO2max. ...
The purpose of this systematic review and meta-analysis is to assess the effect of concurrent high intensity interval training (HIIT) and resistance training (RT) on strength and hypertrophy. Five electronic databases were searched using terms related to HIIT, RT, and concurrent training. Effect size (ES), calculated as standardised differences in the means, were used to examine the effect of concurrent HIIT and RT compared to RT alone on muscle strength and hypertrophy. Sub-analyses were performed to assess region-specific strength and hypertrophy, HIIT modality (cycling versus running), and inter-modal rest responses. Compared to RT alone, concurrent HIIT and RT led to similar changes in muscle hypertrophy and upper body strength. Concurrent HIIT and RT resulted in a lower increase in lower body strength compared to RT alone (ES = −0.248, p = 0.049). Sub analyses showed a trend for lower body strength to be negatively affected by cycling HIIT (ES = −0.377, p = 0.074) and not running (ES = −0.176, p = 0.261). Data suggests concurrent HIIT and RT does not negatively impact hypertrophy or upper body strength, and that any possible negative effect on lower body strength may be ameliorated by incorporating running based HIIT and longer inter-modal rest periods.
... 'all-out', rate of perceived exertion and number of bouts performed) in order to accomplish the 7-8 bouts proclaimed by Tabata et al. (1996). For example, Laird et al. (2016) used 110%, 115% and 120% of i _ VO 2 max. We speculate that inconsistencies in Tabata's Protocol intensity prescription could be related to poor pretesting description on the original articles. ...
... Regarding the type of the study, 16 (53Á3%) of the reviewed studies were acute and 14 (46Á6%) were chronic studies (Tables S2 and S3). The analyses involved _ VO 2 max (Vuorimaa et al., 2000;Feriche et al., 2007;Fortner et al., 2014;Stanley et al., 2014;Nicol o et al., 2015;Williams & Kraemer, 2015), lactate levels (Feriche et al., 2007;Amtmann et al., 2008;Farney et al., 2012;Fortner et al., 2014;Invernizzi et al., 2014;Stanley et al., 2014;Nicol o et al., 2015), perceived exertion (Amtmann et al., 2008;Farney et al., 2012;Fortner et al., 2014), heart rate (Farney et al., 2012;Fortner et al., 2014;Stanley et al., 2014;Nicol o et al., 2015;Williams & Kraemer, 2015), total work (Farney et al., 2012;Morifuji et al., 2012;Scribbans et al., 2014a;Nicol o et al., 2015;Williams & Kraemer, 2015;Harnish & Sabo, 2016), caloric expenditure (Williams & Kraemer, 2015), oxidative stress (Farney et al., 2012), blood glucose, insulin and plasma concentration of amino acids (Morifuji et al., 2012), blood pressure (Buchan et al., 2011a,b;Fortner et al., 2014;Stanley et al., 2014;Foster et al., 2015), fibre-type distribution, whole-muscle capillary density (Scribbans et al., 2014a), power output (Foster et al., 2015;Holmstrup et al., 2016;Laird et al., 2016;Mat e-Muñoz et al., 2017), inflammatory markers (cytokines, interleukin-6 and interleukin-10), tumour necrosis factor (TNF-a) and insulin sensitivity (Harnish & Sabo, 2016). ...
... The advantage of the very low-volume HIIT could be related to time efficiency (~10% of the time expended on endurance training). Among the seven chronic studies that compared the Tabata Protocol with other forms of exercise, two (McRae et al., 2012;Scribbans et al., 2014a) reported better results and five (Buchan et al., 2011a,b;Foster et al., 2015;Holmstrup et al., 2016;Laird et al., 2016) reported equivalent results to others forms of exercise. Consequently, we can infer that the merit of the Tabata Protocol is in its time efficiency more than in its superiority in comparison with traditional protocols. ...
... The final selection had nine articles, totaling 231 adults. Among the selected studies, four performed interventions in samples with eutrophic nutritional status [20][21][22][23] and five in overweight populations [24][25][26][27][28] 21,24,25,27,28 , seven muscle strength of lower limbs (leg press) and / or upper limbs (bench press) 20-26 and seven cardiorespiratory fitness, specifically VO 2max in kg / ml / min. 20,22,[24][25][26][27][28] . ...
... Among the selected studies, four performed interventions in samples with eutrophic nutritional status [20][21][22][23] and five in overweight populations [24][25][26][27][28] 21,24,25,27,28 , seven muscle strength of lower limbs (leg press) and / or upper limbs (bench press) 20-26 and seven cardiorespiratory fitness, specifically VO 2max in kg / ml / min. 20,22,[24][25][26][27][28] . ...
... In studies that used interval training, five used the combination of the HIIT protocol with strength training 21,[23][24][25]28 , while four adopted the SIT principles for combined training 20,22,26,27 . ...
Interval training (HIIT / SIT) combined with resistance training (RT) has been highlighted as a strategy for the improvement of health-related physical fitness markers (HRPF) in adults. Thus, the aim of this meta-analysis was to compare the efficacy of combined training (HIIT / SIT + RT) with other exercise protocols on HRPF markers in adults. A systematic search was performed in MEDLINE via PebMed, Cochrane-CENTRAL, SPORTDiscus, LILACS, SCIELO and Scopus databases between January and March 2017, using the following keywords in English and Portuguese: physical fitness, high-intensity interval training, sprint interval training, resistance training and adults. The quality of studies was evaluated using the PEDro scale. After applying both inclusion and exclusion criteria, nine articles were selected (n = 231). The extraction of means and standard deviations from studies was performed independently by two authors and the RevMan software was used to perform the meta-analysis. Combined training interventions lasted from 6 to 12 weeks and generated greater increase in maximal oxygen uptake than other forms of exercise. The combination of interval training and strength training may be considered more effective to improve aerobic capacity levels in adults.
... There are conflicting opinions regarding whether concurrent training is beneficial, with studies reporting a synergistic enhancement in aerobic and strength outcome measures [2,[5][6][7][8], whilst others have observed an interference, where concurrent training results in an observed gain in either aerobic or strength outcomes whilst attenuating the adaptation of the other [9][10][11]. When developing an exercise training program, the mode, intensity, and volume of training need to be considered to mitigate or reduce any adaptation interference effects [2,4]. ...
... 2024, 14, 8447 8 of 11 improvements in aerobic power and the measures of dynamic explosive movement. The lack of synergistic enhancements observed in the aerobic and strength outcome measures are in line with some previous literature [9][10][11], whilst in contrast to others [2,[5][6][7][8]. These contradictory findings most likely reflect the exploratory study design, training program, exercise selection choices for both ET and RT, and recovery time. ...
There is conflicting evidence on whether concurrent aerobic endurance and resistance training (RT) leads to synergistic enhancements in aerobic capacity and muscular strength or causes interference, limiting performance gains. We developed a concurrent training (CT) intervention, including full-body dynamic RT combined with high-intensity interval training (HIIT), on a cycle ergometer to determine whether a brief CT intervention is beneficial to both muscular strength and aerobic capacity. In an exploratory pilot study, participants (n = 10; male = 4) undertook a four-week CT intervention consisting of RT, including six compound movements (bench press, squat, deadlift, Pendley row, squat jumps, and rack pulls), plus cycle HIIT. The pre-/post-intervention improvements were assessed via bench press and leg press 3RM testing, an isometric mid-thigh pull, a countermovement jump, and the change in the relative V˙O2max. We observed significant (p < 0.1) increases in the bench press (6.4%), leg press (6.7%), IMTP (11.1%), and relative V˙O2max (7%) results. Interestingly, the participants with the highest pre-intervention relative V˙O2max demonstrated no performance improvements. These pilot test results suggest that CT is an effective strategy that enables synergistic enhancements that can be observed with very low training volumes. This suggests that CT is an effective strategy for improving muscular strength and aerobic endurance in non-elite physically active individuals.
... A meta-analysis found increments on aerobic exercise performance after a SIT program (Gist et al., 2014;Sloth et al., 2013). Interval training combined with concurrent training has shown positive effects in VO2max in young adult women (Laird et al., 2016), older women (Salom Huffman et al., 2019), as well as the SIT training alone in diverse studies (Boullosa et al., 2022;Sloth et al., 2013). Our study did not result in significant changes in VO2max, even though our subjects were not participating in a regular schedule of exercise. ...
... Our study showed that young women significantly improved strength as measured by bench press and back squat, implying that for recreational active women a program combining SIT and strength training programs would allow women to improve physiological variables that could attenuate health and quality of life. As shown by previous studies that combined SIT and concurrent resistance training, authors found positive effects on muscular performance in women (Laird et al., 2016). ...
Background: Exercise has positive effects on overall health and reduces risk for several chronic diseases. Diverse program modalities are growing as a potential intervention to improve physiological and psychological outcomes. Purpose: The present study examines the effect of a 10-week sprint interval training (SIT) and resistance training program on physiological and psychological variables in young women. Methods: 37 women (M Age = 24.9±4.3, BMI = 24.7±4.3) participated in a 10-week exercise intervention, consisting of a SIT treadmill protocol and resistance training three times a week for a total of 30 sessions. Participants were randomly assigned to one of two SIT programs (0% incline and 6% incline) and assessed at baseline and post testing for body composition, muscular strength and aerobic fitness. Enjoyment was assessed via a semi-structured interview following the intervention. Results: There were no significant group by time interactions. There was a significant reduction in body fat percentage (p<0.001, Δ 2.23% & 2.52% respectively), as well as a significant increase in lean mass (p<0.001, Δ 2.59 kg & 2.56 kg, respectively), bench press (p<0.001, Δ 25.87 kg & 24.4 kg, respectively), back squat (p<0.001, Δ 69.7 kg & 64.3 kg, respectively) following the intervention for both groups. There were no significant changes in aerobic fitness, kcal intake, and body fat mass. Overall participants reported enjoying the protocol but expressed apprehension of continuing the exercise on their own. Conclusions: Our current data suggest that a SIT and resistance program accounts for positive changes on physiological and psychological variables like percentage of body fat reductions and lean mass increments, muscular strength and exercise enjoyment.
... Considering the different effects of various exercise types on cancer cachexia, a combination of different types of exercise could provide a better result for counteracting cancer cachexia. Combined exercise downregulates inflammation, improves body composition, and increases the strength of skeletal muscle, more than resistance or aerobic exercise alone [18,[77][78][79][80]. ...
... Considering the different effects of exercise type on cancer cachexia, a combination of different types of exercise could provide a better result for counteracting cancer cachexia. Combined exercise downregulates inflammation, improves body composition, and increases the strength of skeletal muscle, more than resistance or aerobic exercise alone [18,[77][78][79][80]. ...
Cancer cachexia is a syndrome experienced by many patients with cancer. Exercise can act as an autophagy modulator, and thus holds the potential to be used to treat cancer cachexia. Autophagy imbalance plays an important role in cancer cachexia, and is correlated to skeletal and cardiac muscle atrophy and energy-wasting in the liver. The molecular mechanism of autophagy modulation in different types of exercise has not yet been clearly defined. This review aims to elaborate on the role of exercise in modulating autophagy in cancer cachexia. We evaluated nine studies in the literature and found a potential correlation between the type of exercise and autophagy modulation. Combined exercise or aerobic exercise alone seems more beneficial than resistance exercise alone in cancer cachexia. Looking ahead, determining the physiological role of autophagy modulated by exercise will support the development of a new medical approach for treating cancer cachexia. In addition, the harmonization of the exercise type, intensity, and duration might play a key role in optimizing the autophagy levels to preserve muscle function and regulate energy utilization in the liver.
... However, the literature remains inconclusive. Often, "interference" effects are not always reported; some studies have demonstrated similar gains in strength and hypertrophy (17,43,50,51), whereas others have shown that, under certain conditions, concurrent exercise induced greater hypertrophic adaptations than resistance-only training (40,49). ...
The purpose of this systematic review with meta-analysis was to explore the effects of concurrent resistance and endurance training (CT) incorporating continuous or intermittent endurance training (ET) on whole- muscle and type I and II muscle fiber hypertrophy compared with resistance training (RT) alone. Randomized and nonrandomized studies reporting changes in cross-sectional area at muscle fiber and whole-muscle levels after RT compared with CT were included. Searches for such studies were performed in Web of Science, PubMed, Scopus, SPORTDiscus, and CINAHL electronic databases. The data reported in the included studies were pooled in a random-effects meta-analysis of standardized mean differences (SMDs). Twenty-five studies were included. At the whole-muscle level, there were no significant differences for any comparison (SMD , 0.03). By contrast, RT induced greater type I and type II muscle fiber hypertrophy than CT when high-intensity interval training (HIIT) was incorporated alone (SMD . 0.33) or combined with continuous ET (SMD . 0.27), but not compared with CT incorporating only continuous ET (SMD , 0.16). The subgroup analyses of this systematic review and meta-analysis showed that RT induces greater muscle fiber hypertrophy than CT when HIIT is included. However, no CT affected whole-muscle hyper- trophy compared with RT
... Laird et al. believe that the continuous running and natural running training methods of sprint training are aerobic training methods. These methods are characterized by low intensity and large exercise measurement; although, such training methods are very helpful to improve the endurance of athletes [7]. ...
Node localization and temporal synchronization, as two key parts of each self-organized and localization-aware wireless sensor network (WSN), have been a key topic for research and applications. The initial prototype of the sensor network is the same as that of the local area network. All nodes are connected by wires, and there is a central control node. All nodes transmit data to the central node point-to-point. With the development and progress of wireless communication technology, the current sensor network has developed into a WSN. Without a central node, all nodes can communicate with each other; so, it is natural to develop positioning technology in WSN. Node positioning in wireless sensor networks refers to the process in which sensor nodes determine the location information of other nodes in the network through a certain positioning technology based on the location information of a few known nodes in the network. The principle of positioning is purely geometric in mathematics. With the in-depth promotion of WSN in the application field, there are more and more requirements for high precision positioning, the higher the positioning accuracy, the higher the requirements for network time synchronization, and the problem of node clock synchronization and high precision positioning of the node can be studied together. Solving the problem of node clock synchronization can further provide support for node positioning in a variety of different environments. As a new ultrabroadband (UWB) carrier-free communication technology with nanoscale temporal resolution, it has been widely used in high-precision node positioning systems in recent years, UWB technology is the most advanced noncarrier wireless communication technology that uses bandwidths above 1 GHz and uses nonsine wave narrow pulses from nanoseconds to picoseconds to transmit data. Therefore, it occupies a very wide spectrum. UWB technology has the advantages of low system complexity, low transmit signal power spectrum density, insensitive to channel fading, and high positioning accuracy. It is especially suitable for high-speed wireless access in dense multipath places such as indoors, providing a technical basis for the engineering implementation of high-precision positioning algorithms. However, the current situation of Chinese track and field events has not kept pace with the development of Chinese competitive sports, and even the level of individual events has a gradual decline. Therefore, it is very meaningful to study the relevant biological factors that affect sprint performance. This article analyzes the related biological factors that affect the performance of the sprint, combines the knowledge of physiology to analyze the training methods that appear in the sprint from the physiological perspective, and analyzes the related biological factors that affect the performance of the sprint. This article chooses to divide them into men’s group (3 groups) and women’s group (3 groups), with 4 people in each group. Experiment proved that after the experiment, these are the following factors: the fatigue of the nervous system, the technical difference of sprinting, the change of muscle fiber enzyme activity, the order of muscle fiber cross-sectional area and muscle activation, and the recruitment of muscle fiber types. Impact P value less than 0.05, which shows that the factors that affect sprint performance are complex, and the biological factors that affect step length can be studied through anthropometry. The impact of step frequency on sports performance is very important.
... In this way, the stimulation of the AMPK axis therefore has the potential to reduce the post-exercise MPS response, attenuating strength training adaptations (Baar, 2006). Nonetheless, such 'interferences' are not consistently observed as comparable improvements in resistance training adaptations have been found in concurrent versus resistance training alone (Cantrell et al., 2014;Glowacki et al., 2004;Laird et al., 2016;McCarthy et al., 1995;McCarthy et al., 2002). This apparent 'control' of the adaptive response may relate to the manipulation of variables such as exercise order (Cadore et al., 2012), between mode recovery duration (Lee et al., 2020), exercise modes (Moberg et al., 2021), training frequency, intensity, and volume (Fyfe et al., 2014;Murach & Bagley, 2016;Wilson et al., 2012) and nutrient availability (Camera et al., 2015). ...
Despite more than four decades of research examining the physical demands of match-play, quantification of the customary training loads of adult male professional soccer players is comparatively recent. The training loads experienced by players during weekly micro-cycles are influenced by phase of season, player position, frequency of games, player starting status, player-specific training goals and club coaching philosophy. From a macronutrient perspective, the periodization of physical loading within (i.e., match versus training days) and between contrasting micro-cycles (e.g., 1, 2 or 3 games per week schedules) has implications for daily carbohydrate (CHO) requirements. Indeed, aside from the well-recognised role of muscle glycogen as the predominant energy source during match-play, it is now recognised that the glycogen granule may exert regulatory roles in activating or attenuating the molecular machinery that modulate skeletal muscle adaptations to training. With this in mind, the concept of CHO periodization is gaining in popularity, whereby CHO intake is adjusted day-by-day and meal-by-meal according to the fuelling demands and specific goals of the upcoming session. On this basis, the present paper provides a contemporary overview and theoretical framework for which to periodize CHO availability for the professional soccer player according to the "fuel for the work" paradigm.
... These findings may explain why the effect size distribution for concurrent training was not shifted downwards in the present meta-analysis, given most of the included studies comprised untrained or recreationally trained participants and their window of adaptation available for strength may nullify the potential for interference (89). Moreover, the results of the present meta-analysis reflect contemporary research (91,92) demonstrating no or minimal interference in comparison to earlier concurrent research (93,94). Where strength training is the dominant training modality and primary focus, the use of novel endurance methods such as interval training (91, 92) may reduce moderating factors, such as training volume that are linked to greater interference (89). ...
... The final analyses included 15 studies 11,12,31,[44][45][46]48,53,54,58,61,[66][67][68][69] , including 201 participants performing combined aerobic and strength training and 188 participants performing sole strength training. The observed SMD in the individual studies ranged from -0.67 to 0.28. ...
Objective:
This systematic review assessed the compatibility of concurrent aerobic and strength training compared to sole strength training regarding adaptations in muscle function (maximal and explosive strength) and muscle mass. Subgroup analyses were conducted to examine the impact of training modality, exercise type, exercise order, training frequency, age, and training status.
Design:
A systematic literature search was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). PROSPERO: CRD42020203777
Data sources:
PubMed/MEDLINE, ISI Web of Science, Embase, CINAHL, SPORTDiscus and Scopus were systematically searched (12th of August 2020, updated on the 15th of March 2021).
Eligibility criteria:
Population: Healthy adults of any sex and age; Intervention: Supervised, concurrent aerobic and strength training of at least 4 weeks; Comparison: Sole strength training with matched strength training volume; Outcome: maximal strength, explosive strength and muscle hypertrophy.
Results:
A total of 43 studies were included. The estimated average standardised mean differences (SMD) based on the random-effects model were -0.06 (95% CI: -0.20, 0.09, p=0.446), -0.28 (95% CI: -0.48, - 0.08, p=0.007) and -0.01 (95% CI: -0.16, 0.18, p=0.919) for maximal strength, explosive strength and muscle hypertrophy, respectively. The attenuation in explosive strength was more pronounced when concurrent training was performed within the same session (p=0.043) compared with separating the sessions by at least 3 h (p>0.05). Summary/Conclusion:
Concurrent aerobic and strength training does not compromise muscle hypertrophy and maximal strength development. However, explosive strength gains may be attenuated, especially when aerobic and strength training are performed within the same session.
... Convolutional neural network is a well-known deep learning framework inspired by the mechanism of natural visual perception. It is a multilevel deep feedforward artificial neural network composed of multiple two-dimensional planes [12,13]. Its neurons can respond to some surrounding units within the coverage area and have achieved very good results in image processing problems. ...
With the development of deep learning and its wide application in the field of natural language, the question and answer research of knowledge graph based on deep learning has gradually become the focus of attention. After that, the natural language query is converted into a structured query sentence to identify the entities and attributes in the user’s natural language query and the specified entities and attributes are used to retrieve answers to the knowledge graph. Using the advantage of deep learning in capturing sentence information, it incorporates the attention mechanism to obtain the semantic vector of the relevant attributes in the query and uses the parameter sharing mechanism to insert candidate attributes into the triple in the same model to obtain the semantic vector of typical candidates. The experiment measured that under the 100,000 RDF dataset, the single entity query of the MIQE model does not exceed 3 seconds, and the connection query does not exceed 5 seconds. Under the one-million RDF dataset, the single entity query of the MIQE model does not exceed 8 seconds, and the connection query will not be more than 10 seconds. Experimental data show that the system of knowledge-answering questions of engineering of intelligent construction based on deep learning has good horizontal scalability.
... However, compared to resistance-only training, concurrent training may compromise strength, power, and/or hypertrophic adaptations, which is commonly referred to as the "interference effect" [1,2]. Nonetheless, such interference is not consistently observed, as comparable improvements in muscle strength and hypertrophy have also been reported following concurrent versus resistance-only training [3][4][5][6][7]. The potential for, and the degree of, interference may relate to the chosen dependent variables and performance tests [8], as well as the manipulation of training variables (e.g., exercise order, between-mode recovery duration, exercise mode, frequency, intensity, volume [1,9,10]), and 'non-training' variables (e.g., participant training status and nutrient availability [8,11]). ...
Background
The importance of concurrent exercise order for improving endurance and resistance adaptations remains unclear, particularly when sessions are performed a few hours apart. We investigated the effects of concurrent training (in alternate orders, separated by ~3 hours) on endurance and resistance training adaptations, compared to resistance-only training.
Materials and methods
Twenty-nine healthy, moderately-active men (mean ± SD; age 24.5 ± 4.7 y; body mass 74.9 ± 10.8 kg; height 179.7 ± 6.5 cm) performed either resistance-only training (RT, n = 9), or same-day concurrent training whereby high-intensity interval training was performed either 3 hours before (HIIT+RT, n = 10) or after resistance training (RT+HIIT, n = 10), for 3 d.wk⁻¹ over 9 weeks. Training-induced changes in leg press 1-repetition maximal (1-RM) strength, countermovement jump (CMJ) performance, body composition, peak oxygen uptake (V˙O2peak), aerobic power (W˙peak), and lactate threshold (W˙LT) were assessed before, and after both 5 and 9 weeks of training.
Results
After 9 weeks, all training groups increased leg press 1-RM (~24–28%) and total lean mass (~3-4%), with no clear differences between groups. Both concurrent groups elicited similar small-to-moderate improvements in all markers of aerobic fitness (V˙O2peak ~8–9%; W˙LT ~16-20%; W˙peak ~14-15%). RT improved CMJ displacement (mean ± SD, 5.3 ± 6.3%), velocity (2.2 ± 2.7%), force (absolute: 10.1 ± 10.1%), and power (absolute: 9.8 ± 7.6%; relative: 6.0 ± 6.6%). HIIT+RT elicited comparable improvements in CMJ velocity only (2.2 ± 2.7%). Compared to RT, RT+HIIT attenuated CMJ displacement (mean difference ± 90%CI, -5.1 ± 4.3%), force (absolute: -8.2 ± 7.1%) and power (absolute: -6.0 ± 4.7%). Only RT+HIIT reduced absolute fat mass (mean ± SD, -11.0 ± 11.7%).
Conclusions
In moderately-active males, concurrent training, regardless of the exercise order, presents a viable strategy to improve lower-body maximal strength and total lean mass comparably to resistance-only training, whilst also improving indices of aerobic fitness. However, improvements in CMJ displacement, force, and power were attenuated when RT was performed before HIIT, and as such, exercise order may be an important consideration when designing training programs in which the goal is to improve lower-body power.
... For example, one can compare the training loads in futsal in which men during the match on average run about 4,000 m [2] while women only about 2,730 m [4]. It was also found that women's physical performance in soccer depends significantly on the level of VO 2 max [19], as well as on the amount of anaerobic power developed in strength and speed training [17]. ...
Background:
The somatic features of the athletes’ bodies partially determine their sporting level and are conditioned to a large extent by the state of nutrition.
Objective:
The aim of this paper is to present nutritional status and its correlation with the somatic determinants of training athletes and physical education students.
Material and methods:
This study involved 12 weightlifting players (subgroup-WL), 15 soccer players (subgroup-SP), 12 table tennis players (subgroup-TT) and 12 female students of physical education (subgroup-C). In all subjects, the age and somatic variables were recorded and the daily intake of energy, water, proteins, fats and carbohydrates was determined by 24-h dietary recalls.
Results:
Although the analysis of variance did not show significant differences in somatic variables and nutrition data, post hoc analysis showed significant differences between some subgroups in terms of age, BMI, fat content (BF), fat-free mass (FFM) and the amount of water, protein and carbohydrates consumed during the day. It was also shown that somatic variables correlated with relatively expressed amounts of energy, proteins and carbohydrates consumed in individual subgroups, as well as in the whole group formed from all subgroups of studied women. In addition, there were significant correlations between somatic variables and the total amount of water consumed in the whole group and the total amount of protein consumed in subgroup C (p<0.05), as well as the total amount of fat consumed in subgroup WL.
Conclusions:
In summary, it was found that the examined women used an abnormal hypoenergetic diet with too low carbohydrate content in which were more useful relative than absolute amounts of consumed proteins, fats and carbohydrates.
In this unfavorable situation, dietary education of the respondents seems to be necessary.
... two SIT sessions (4-6 x 20-s) and two strength sessions (3 x 4-6 at 85% 1RM) on nonconsecutive days per week for 12 weeks. Moreover, the authors reported that the magnitude of change in lower body strength was greater in the concurrent group suggesting that SIT does not interfere with strength development but may provide an additional stimulus (Cantrell et al, 2014) A recent study by Laird et al (2016) in recreationally active females provided further evidence that both SIT and ST can be completed concurrently without attenuation of strength adaptations and provide greater adaptations than either alone. Participants in the concurrent group completed 3 sessions per week for 10 weeks with both SIT (8 x 20s treadmill running at 110-120% Velocity at VO 2max (VVO 2max interspersed with 10s passive recovery) and ST (Alternating rep schemes; 5x3, 4x5, 3x10 on lower and upper body) occurring on the same day but separated by 4 hours to minimise molecular interference (Murach and Bagley, 2016). ...
It is estimated that 50% of the UK population do not meet the recommended exercise
guidelines, with both ‘lack of time’ and ‘perception of effort’ commonly cited barriers to
participation. Sprint interval training (SIT) has emerged as a more time efficient alternative to
moderate intensity continuous training (MICT) for improving health and fitness. Recently,
similar findings for low vs. high volume responses to longer duration bouts of SIT (>20s) have
been found. However, the dose response of shorter bouts of SIT (< 10s), which may be better
tolerated, is unknown, as are the residual effects once the training stimulus is removed.
Thirteen healthy inactive males were matched for VO2peak and assigned to either a low dose
(LDG) (n=7) or a high dose (HDG) (n= 6) supervised 6-week concurrent SIT intervention,
which began immediately after the completion of a 6-week control period (BL 1 & 2).
Participants performed 2/wk of SIT (LDG = 2 sets of 5 x 6s ON: 18s OFF bouts; HDG = 4 -
6 sets of 5 x 6s:18s bouts) and x1/wk resistance training (3 exercises @ 3x10 reps). Participants
were tested at BL 1 & 2, post intervention and after a 3 wk period of training cessation for
indices of physiological health including exercise capacity, blood lipid profile and body
composition.
VO2peak significantly increased by 16% in the LDG (32.3 ± 7.6 to 37.6 ± 10.0 ml.kg.-1.min-1;
p<0.001) and 11% in the HDG (34.4 ± 3.1 to 38.1 ± 3.8 ml.kg.-1.min-1; p<0.001). Following 3
wk of training cessation, VO2peak decreased by 11% in the LDG (37.6 ± 10.0to 33.4 ± 9.4
ml.kg.-1.min-1; p< 0.05) and increased by 3% in the HDG (38.1 ± 3.8to 39.2 ± 4.2 ml.kg.-1.min-
1; p>0.05). TTE had increased in both groups (LDG; +, 9%, HDG; +7%) post intervention. At
3 wk post TTE had decreased in the LDG (-9%) and increased in the HDG (+1%). DBP
significantly decreased in both groups (LDG; -9%, HDG; -5%). Total cholesterol (TC)
significantly decreased in both groups (LDG; -16%, HDG; -7%). At 3 wk post TC increased
in both groups (LDG; +15%, HDG; +6%). A significant increase of 5% in thigh girth was
found in the LDG post intervention. Leg press strength significantly increased in both groups
(LDG; +41%, HDG; +36). At 3 wk post leg press strength decreased in both groups (LDG; -
4%, HDG; -14%), Seated row strength increased in both groups (LDG; + 21%, HDG; +23%).
At 3 wk post seated row strength decreased in both groups (LDG; -4%, HDG; -8%). . Seated
press strength increased in both groups (LDG; + 4%, HDG; +14%). At 3 wk post seated press
strength decreased in both groups (LDG; -8%, HDG; -15%).
Both the LDG and the HDG improved indices of health and performance similarly after 6
weeks, suggesting that the LDG is as effective as the HDG, despite a considerably reduced
volume. However, the findings following a 3 wk period of training cessation suggests that the
HDG may have experienced a temporary state of cumulative fatigue ‘over-reaching’ post
intervention, which may have negatively affected aerobic indices of performance.
... In addition to lower volume, successful outcomes were seen in studies where RT training was performed before END training. Both Laird et al. [18] and McCarthy, Agre, Graf, Pozniak and Vailas [19] had participants train three days a week and scheduled END work after RT; one group four hours after and another group immediately after respectively. Both groups saw no interference effect and realized positive strength adaptations. ...
... Maximal aerobic speed improved throughout the training program with no difference between groups (7.3% for CT and 3.5% for ST after 12 weeks). Although improvement in the ST group was not expected, a recent study also showed an enhancement of the maximal aerobic speed after both strength-only and concurrent training in recreationally active females (Laird et al., 2016). This finding could be explained by enhanced efficiency of the neuromuscular system via improved coordination and motor unit recruitment, as well as morphological and musculotendinous stiffness alterations (Beattie et al., 2014). ...
The purpose of this study was to compare maximal strength gains during strength training (ST) and concurrent training (CT) consisting of high-intensity intermittent training plus strength training over the course of a 12-week intervention. A secondary purpose was to examine the relationship between strength training volume and strength gain in both groups. Nineteen recreationally active males were divided into CT (n = 11) and ST (n = 8) groups. The CT group performed repeated 1 min efforts at 100% of maximal aerobic speed interspersed by 1 min of passive recovery until accumulating a total running distance of 5km followed by a strength session (consisting of three sets of seven exercises with loads of 8-12 repetition maximum) twice weekly for a period of 12 weeks. The ST group performed only strength training sessions during the same 12-week period. Strength training total volume-load (Σ repetitions x load) for the upper- and lower-body was computed, while maximal strength (1RM) was evaluated at baseline, week 8, and week 12. Lower-body volume-load over 12 weeks was not different between groups. Absolute 1RM increased in both groups at week 8 and week 12, while 1RM relative to body mass increased in both groups at week 8, but only ST increased relative maximum strength between week 8 and week 12. There was a statistically significant correlation between strength training lower-body volume-load and maximum strength change between baseline and week 8 for the CT group (r = 0.656), while no significant correlations were found for the ST group. In summary, executing high-intensity intermittent exercise twice a week before strength training did not impair maximal strength after 8 weeks, however, only ST demonstrated an increase in relative strength after 12 weeks.
... Since that seminal study, numerous investigations [18][19][20][21][22][23] have confirmed observations of compromised strength gains when strength and endurance training are undertaken concurrently. In contrast, others [25,[52][53][54][55][56][57] have reported little or no impairments to strength when undertaking concurrent training. Such disparities may be attributed a number of factors including volume, intensity and frequency of sessions, as well as training status of participants, modes of exercise being employed, and duration of intervention [14]. ...
Background
We implemented a high-protein diet (2 g·kg⁻¹·d⁻¹) throughout 12 weeks of concurrent exercise training to determine whether interferences to adaptation in muscle hypertrophy, strength and power could be attenuated compared to resistance training alone.
Methods
Thirty-two recreationally active males (age: 25 ± 5 years, body mass index: 24 ± 3 kg·m⁻²; mean ± SD) performed 12 weeks of either isolated resistance (RES; n = 10) or endurance (END; n = 10) training (three sessions·w⁻¹), or concurrent resistance and endurance (CET; n = 12) training (six sessions·w⁻¹). Maximal strength (1RM), body composition and power were assessed pre- and post-intervention.
Results
Leg press 1RM increased ~ 24 ± 13% and ~ 33 ± 16% in CET and RES from PRE-to-POST (P < 0.001), with no difference between groups. Total lean mass increased ~ 4% in both CET and RES from PRE-to-POST (P < 0.001). Ultrasound estimated vastus lateralis volume increased ~ 15% in CET and ~ 11% in RES from PRE-to-POST (P < 0.001), with no difference between groups. Wingate peak power relative to body mass displayed a trend (P = 0.053) to be greater in RES (12.5 ± 1.6 W·kg BM⁻¹) than both CET (10.8 ± 1.7 W·kg BM⁻¹) and END (10.9 ± 1.8 W·kg BM⁻¹) at POST. Absolute VO2peak increased 6.9% in CET and 12% in END from PRE-to-POST (P < 0.05), with no difference between groups.
Conclusion
Despite high protein availability, select measures of anaerobic power-based adaptations, but not muscle strength or hypertrophy, appear susceptible to ‘interference effects’ with CET and should be closely monitored throughout training macro-cycles.
Trials Registry: This trial was registered with the Australian-New Zealand Clinical Trials Registry (ACTRN12617001229369).
Electronic supplementary material
The online version of this article (10.1007/s40279-018-0999-9) contains supplementary material, which is available to authorized users.
... It is hypothesized that the ability to train this capacity is genetically determined [7]. At the present stage of knowledge there is evidence that beyond the biological natural development of the body, strength training is most likely to develop anaerobic performance in both women and men [8,9]. In addition, plyometric training of lower limbs influenced the increase of the results in vertical and horizontal jumps, the shortening of the running time over the distance of 20 and 40 m and the increased strength of these limbs [10]. ...
Introduction. Anaerobic power is an important factor determining the physical performance in various kinds of sports. Therefore, the aim of this paper is to present women’s anaerobic power in soccer players (SP), table tennis players (TT) and weightlifters (WL). Methods. This study involved 3 groups of professional athletes women: 15 SP, 12 TT and 12 WL, which are of a similar age and sports’ level. Anaerobic power in all athletes was recorded during 30-second Wingate test, with resistance set at 0,075 kp x kg (–1). Results. Relatively expressed total external work (TW), maximal power output (Pmax) and the fatigue index (FI) of tested athletes were similar. Mean power (Pmean) was different among the treatment groups (F=12,445; p<0,001), while in TT group these values were significantly lower than in SP and in WL athletes. Somatic variables in 3 groups of tested athletes have not changed. Conclusions. Type of practiced sport has an impact on the size of anaerobic power. Several years of sports training in table tennis has not changed the anaerobic potential of surveyed women while specific training in soccer and weightlifting increased only Pmean.
... In a recent randomised controlled trial (RCT), adding sprint intervals to a concurrent exercise programme provided greater benefits than only RT in young obese women. 15 Likewise, a recent systematic review and meta-analyse on 2247 overweight and/or obese children and adolescents 12 observed significant improvements in lipid profiles and body composition after long-term (ie, 6-52 weeks) interventions that combined RT and AT. However, despite the rising prevalence of obesity, and the multiple position stands promoting exercise for the treatment of obesity and cardiometabolic health, a meta-analytic approach has not previously been used to examine the effects of concurrent exercise compared with AT alone in the obese paediatric population. ...
Objective. To determine if the combination of aerobic and resistance exercise is superior to aerobic exercise alone for the health of obese children and adolescents.
Design: Systematic review with meta-analysis.
Data sources: Computerized search of three databases (MEDLINE, EMBASE, and
Cochrane Controlled Trials Registry).
Eligibility criteria for selecting studies: Studies that compared the effect of supervised concurrent exercise vs. aerobic exercise interventions, with anthropometric and metabolic outcomes in paediatric obesity (6 to 18 years old). The mean differences (MD) of the parameters from pre- to post-intervention between groups were pooled using a random-effects model.
Results. 12 trials with 555 youths were included in the meta-analysis. Compared to aerobic exercise alone, concurrent exercise resulted in greater reductions in body mass (MD= –2.28 kg), fat mass (MD= –3.49%; and MD= –4.34 kg) and low-density lipoprotein cholesterol (MD= –10.20 mg/dL); as well as greater increases in lean body mass (MD= 2.20 kg) and adiponectin level (MD= 2.59 μg/mL). Differences were larger for longer-term programs (>24 weeks).
Summary: Concurrent aerobic plus resistance exercise improves body composition, metabolic profiles, and inflammatory state in the obese paediatric population.
Systematic review registration: CRD42016039807.
Objective
This study aims to compare, through quantitative analysis, the effectiveness of different endurance training types on increasing lower limb strength and muscle cross-sectional area (MCSA) in concurrent training.
Methods
This systematic literature search was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) [PROSPERO ID: CRD42023396886]. Web of Science, SportDiscuss, Pubmed, Cochrane, and Scopus were systematically searched from their inception date to October 20, 2023.
Results
A total of 40 studies (841 participants) were included in this meta-analysis. MCSA analysis showed that, compared to resistance training alone, concurrent high-intensity interval running training and resistance training and concurrent moderate-intensity continuous cycling training and resistance training were more effective (SMD = 0.15, 95% CI = −0.46 to 0.76, and SMD = 0.07, 95% CI = −0.24 to 0.38 respectively), while other modalities of concurrent training not. Lower body maximal strength analysis showed that all modalities of concurrent training were inferior to resistance training alone, but concurrent high-intensity interval training and resistance training showed an advantage in four different concurrent training modalities (SMD = −0.08, 95% CI = −0.25 to 0.08). For explosive strength, only concurrent high-intensity interval training and resistance training was superior to resistance training (SMD = 0.06, 95% CI = −0.21 to 0.33).
Conclusion
Different endurance training types have an impact on the effectiveness of concurrent training, particularly on lower limb strength. Adopting high-intensity interval running as the endurance training type in concurrent training can effectively minimize the adverse effects on lower limb strength and MCSA.
Background
Many sports require maximal strength and endurance performance. Concurrent strength and endurance training can lead to suboptimal training adaptations. However, how adaptations differ between males and females is currently unknown. Additionally, current training status may affect training adaptations.
Objective
We aimed to assess sex-specific differences in adaptations in strength, power, muscle hypertrophy, and maximal oxygen consumption (V˙O2max) to concurrent strength and endurance training in healthy adults. Second, we investigated how training adaptations are influenced by strength and endurance training status.
Methods
A systematic review and meta-analysis was conducted according to PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, and a Cochrane risk of bias was evaluated. ISI Web of science, PubMed/MEDLINE, and SPORTDiscus databases were searched using the following inclusion criteria: healthy adults aged 18–50 years, intervention period of ≥ 4 weeks, and outcome measures were defined as upper- and lower-body strength, power, hypertrophy, and/or V˙O2max. A meta-analysis was performed using a random-effects model and reported in standardized mean differences.
Results
In total, 59 studies with 1346 participants were included. Concurrent training showed blunted lower-body strength adaptations in males, but not in females (male: − 0.43, 95% confidence interval [− 0.64 to − 0.22], female: 0.08 [− 0.34 to 0.49], group difference: P = 0.03). No sex differences were observed for changes in upper-body strength (P = 0.67), power (P = 0.37), or V˙O2max (P = 0.13). Data on muscle hypertrophy were insufficient to draw any conclusions. For training status, untrained but not trained or highly trained endurance athletes displayed lower V˙O2max gains with concurrent training (P = 0.04). For other outcomes, no differences were found between untrained and trained individuals, both for strength and endurance training status.
Conclusions
Concurrent training results in small interference for lower-body strength adaptations in males, but not in females. Untrained, but not trained or highly trained endurance athletes demonstrated impaired improvements in V˙O2max following concurrent training. More studies on females and highly strength-trained and endurance-trained athletes are warranted.
Clinical Trial Registration
PROSPERO: CRD42022370894.
Meta-analysis, Resistance training, Dose-response.
PURPOSE: This pilot study examined possible effects of a low-volume, short-term progressive resistance exercise (PRE) protocol, specifically targeting muscles with predominantly type I fibers (namely soleus, tibialis anterior, vastus medialis, adductor magnus and biceps femoris), on aerobic capacity in young sedentary individuals.
METHODS: Volunteer (19-25 year old) were randomly assigned into one of the three group: PRE (performed progressive resistance training, targeting muscles with predominantly type I fibers, 25 minutes bouts, 3 times/week, for 6 weeks), walking (W) (65-75 % of maximal heart rate, 25 minutes bouts, 3 times/week for 6 weeks) and control group (C) (n=12 for each). Baseline and final evaluations of cardiopulmonary fitness (included VO2 peak, breathing reserve, e.g) was assessed by incremental cardio-pulmonary exercise testing
RESULTS: In PRE group, median value of peak VO2 significantly increased (from 33,55 ml/kg.min⁻¹ to 37,4 ml/kg.min⁻¹, p=0,008) after training, while no significant change was obtained in W and C groups. VO2 peak/fat free mass (FFM) significantly increased from 40,36 ml/kg.min⁻¹ to 45,4 ml/kg.min-1 in PRE group (p= 0,006) but did not change significantly in either W or C group. Breathing reserve at maximum exercise level was 82,4 L (74,8-105,6) before training and this value was 62,4 L (55,2-83,4) after training at PRE group (p=0,003) but did not change significantly in W and C group either.
CONCLUSION: Results implicates that, this time-saving protocol, also suitable for performing in the home environment, could be beneficial for young sedentary individuals who can not perform aerobic exercise.
Background
Both athletes and recreational exercisers often perform relatively high volumes of aerobic and strength training simultaneously. However, the compatibility of these two distinct training modes remains unclear.
Objective
This systematic review assessed the compatibility of concurrent aerobic and strength training compared with strength training alone, in terms of adaptations in muscle function (maximal and explosive strength) and muscle mass. Subgroup analyses were conducted to examine the influence of training modality, training type, exercise order, training frequency, age, and training status.
Methods
A systematic literature search was conducted according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. PubMed/MEDLINE, ISI Web of Science, Embase, CINAHL, SPORTDiscus, and Scopus were systematically searched (12 August 2020, updated on 15 March 2021). Eligibility criteria were as follows. Population: healthy adults of any sex and age; Intervention: supervised concurrent aerobic and strength training for at least 4 weeks; Comparison: identical strength training prescription, with no aerobic training; Outcome: maximal strength, explosive strength, and muscle hypertrophy.
Results
A total of 43 studies were included. The estimated standardised mean differences (SMD) based on the random-effects model were − 0.06 (95% confidence interval [CI] − 0.20 to 0.09; p = 0.446), − 0.28 (95% CI − 0.48 to − 0.08; p = 0.007), and − 0.01 (95% CI − 0.16 to 0.18; p = 0.919) for maximal strength, explosive strength, and muscle hypertrophy, respectively. Attenuation of explosive strength was more pronounced when concurrent training was performed within the same session ( p = 0.043) than when sessions were separated by at least 3 h ( p > 0.05). No significant effects were found for the other moderators, i.e. type of aerobic training (cycling vs. running), frequency of concurrent training (> 5 vs. < 5 weekly sessions), training status (untrained vs. active), and mean age (< 40 vs. > 40 years).
Conclusion
Concurrent aerobic and strength training does not compromise muscle hypertrophy and maximal strength development. However, explosive strength gains may be attenuated, especially when aerobic and strength training are performed in the same session. These results appeared to be independent of the type of aerobic training, frequency of concurrent training, training status, and age.
PROSPERO: CRD42020203777.
El objetivo del estudio fue contrastar la veracidad de las siguientes creencias: 1-El entrenamiento de fuerza y resistencia es incompatible. 2-El entrenamiento de fuerza limita la flexibilidad. 3-Las rutinas divididas son más eficaces que las de cuerpo entero. 4-El entrenamiento de fuerza no es útil para la pérdida de peso, o la mejora de la composición corporal. Se realizó una búsqueda en las siguientes bases de datos: ProQuest, Google Scholar, Scopus, ScienceDirect y Web of Science. Los criterios de selección fueron: a) Artículos escritos en Español o en Inglés. b) Investigaciones primarias con metodología experimental o cuasi-experimental. c) Escritos entre el año 2015 y 2019, salvo para los apartados 2 y 3, que se amplió hasta 2000 y 1990 respectivamente, debido a la escasez de publicaciones. d) La población objeto de estudio fueron adultos sanos que no practicaban deporte a nivel profesional o semiprofesional. e) Artículos que recogen exclusivamente adaptaciones logradas mediante una intervención con entrenamiento. Analizados los estudios, se pudo determinar que en adultos sanos: 1- El entrenamiento de fuerza y resistencia es compatible. 2- El entrenamiento de fuerza no deteriora la flexibilidad, y podría incluso mejorarla. 3- En virtud de los estudios existente, las rutinas divididas y las de cuerpo entero son igualmente eficaces para incrementar la fuerza. Las rutinas de cuerpo entero podrían generar mayor hipertrofia muscular. 4- El entrenamiento de fuerza es eficaz en la mejora de la composición corporal, y podría tener un impacto positivo en biomarcadores cardiovasculares y metabólicos.Abstract. The purpose of the study was to verify the veracity of the following beliefs: 1-Resistance and endurance training are incompatible. 2-Resistance training reduces flexibility. 3-Split body routines are more effective than full-body routines. 4-Resistance training is not useful neither in weight loss programs, nor to change body composition. The following databases were searched: ProQuest, Google Scholar, Scopus, ScienceDirect and Web of Science. The selection criteria were: a) Articles written in Spanish or in English b) Primary research following an experimental or quasi-experimental methodology c) Written between 2015 and 2019, except for section 2 and 3, which was extended until 2000 and 1990 respectively, due to the shortage of publications d) The target population of study were healthy adults who did not practice sports at the professional or semi-professional level e) Papers which include only adaptations achieved through training interventions. Once the studies were analyzed, it was concluded that in healthy adults: 1-The combination of resistance and endurance training is compatible. 2- Strength training does not decrease flexibility, and it could even improve it. 3- On the basis of existing studies, split and full-body routines are equally effective in improving strength. Full-body routines could generate higher muscle hypertrophy. 4- Strength training is effective in improving body composition, and could make a positive impact on cardiovascular and metabolic biomarkers.
Análisis de la veracidad de determinadas creencias asociadas habitualmente al entrenamiento de fuerza. Una revisión narrativa Analysis of the veracity of certain beliefs frequently associated to resistance training. A narrative review Prince Sultan University (Arabia Saudí) Resumen. El objetivo del estudio fue contrastar la veracidad de las siguientes creencias:1-El entrenamiento de fuerza y resistencia es incompatible. 2-El entrenamiento de fuerza limita la flexibilidad. 3-Las rutinas divididas son más eficaces que las de cuerpo entero. 4-El entrenamiento de fuerza no es útil para la pérdida de peso, o la mejora de la composición corporal. Se realizó una búsqueda en las siguientes bases de datos: ProQuest, Google Scholar, Scopus, ScienceDirect y Web of Science. Los criterios de selección fueron: a) Artículos escritos en Español o en Inglés. b) Investigaciones primarias con metodología experimental o cuasi-experimental. c) Escritos entre el año 2015 y 2019, salvo para los apartados 2 y 3, que se amplió hasta 2000 y 1990 respectivamente, debido a la escasez de publicaciones. d) La población objeto de estudio fueron adultos sanos que no practicaban deporte a nivel profesional o semiprofesional. e) Artículos que recogen exclusivamente adaptaciones logradas mediante una intervención con entrenamiento. Analizados los estudios, se pudo determinar que en adultos sanos: 1-El entrenamiento de fuerza y resistencia es compatible. 2-El entrenamiento de fuerza no deteriora la flexibilidad, y podría incluso mejorarla. 3-En virtud de los estudios existente, las rutinas divididas y las de cuerpo entero son igualmente eficaces para incrementar la fuerza. Las rutinas de cuerpo entero podrían generar mayor hipertrofia muscular. 4-El entrenamiento de fuerza es eficaz en la mejora de la composición corporal, y podría tener un impacto positivo en biomarcadores cardiovasculares y metabólicos. Palabras clave: Entrenamiento concurrente, resistencia, flexibilidad, fuerza. Abstract. The purpose of the study was to verify the veracity of the following beliefs: 1-Resistance and endurance training are incompatible. 2-Resistance training reduces flexibility. 3-Split body routines are more effective than full-body routines. 4-Resistance training is not useful neither in weight loss programs, nor to change body composition. The following databases were searched: ProQuest, Google Scholar, Scopus, ScienceDirect and Web of Science. The selection criteria were: a) Articles written in Spanish or in English b) Primary research following an experimental or quasi-experimental methodology c) Written between 2015 and 2019, except for section 2 and 3, which was extended until 2000 and 1990 respectively, due to the shortage of publications d) The target population of study were healthy adults who did not practice sports at the professional or semi-professional level e) Papers which include only adaptations achieved through training interventions. Once the studies were analyzed, it was concluded that in healthy adults: 1-The combination of resistance and endurance training is compatible. 2-Strength training does not decrease flexibility, and it could even improve it. 3-On the basis of existing studies, split and full-body routines are equally effective in improving strength. Full-body routines could generate higher muscle hypertrophy. 4-Strength training is effective in improving body composition, and could make a positive impact on cardiovascular and metabolic biomarkers.
Osteoarthritis (OA) is a degenerative disease of the articular cartilage with subchondral bone lesions. Osteoarthritis etiologies are mainly related to age, obesity, strain, trauma, joint congenital anomalies, joint deformities, and other factors. Osteoarthritis seriously affects the quality of life; however, there is no effective way to cure osteoarthritis. Aerobic exercise refers to a dynamic rhythmic exercise involving the large muscle groups of the body with aerobic metabolism. More and more evidence shows that exercise has become a useful tool for the treatment of osteoarthritis. This chapter will discuss the role of exercise in the prevention and treatment of osteoarthritis.
Background
Muscular rate of force development (RFD) is positively influenced by resistance training. However, the effects of movement patterns and velocities of training exercises are unknown.
Objectives
To determine the effects of velocity, the intent for fast force production, and movement pattern of training exercises on the improvement in isometric RFD from chronic resistance training.
Methods
A systematic search of electronic databases was conducted to 18 September, 2018. Meta-regression and meta-analytic methods were used to compute standardized mean differences (SMD ± 95% confidence intervals) to examine effects of movement pattern similarity (between training and test exercises; specific vs. non-specific) and movement speed (fast vs. slow vs. slow with intent for fast force production) for RFD calculated within different time intervals.
Results
The search yielded 1443 articles, of which 54 met the inclusion criteria (59 intervention groups). Resistance training increased RFD measured to both early (e.g., 50 ms; standardized mean difference [95% CI] 0.58 [0.40, 0.75]) and later (e.g., 200 ms; 0.39 [0.25, 0.52]) times from contraction onset, as well as maximum RFD (RFDmax; 0.35 [0.21, 0.48]). However, sufficient data for sub-analyses were only available for RFDmax. Significant increases relative to control groups were observed after training with high-speed (0.54 [0.05, 1.03]), slow-speed with intent for fast force production (0.41 [0.20, 0.63), and movement pattern-specific (0.38 [0.17, 0.59]) exercises only. No clear effect was observed for slow-speed without intent for fast force production (0.21 [0.00, 0.42], p = 0.05) or non-movement-specific (0.27 [− 0.32, 0.85], p = 0.37) exercises. Meta-regression did not reveal a significant difference between sexes (p = 0.09); however, a negative trend was found in women (− 0.57 [− 1.51, 0.37], p = 0.23), while a favorable effect was found in men (0.40 [0.22, 0.58], p < 0.001). Study duration did not statistically influence the meta-analytic results, although the greatest RFD increases tended to occur within the first weeks of the commencement of training.
Conclusions
Resistance training can evoke significant increases in RFD. For maximum (peak) RFD, the use of faster movement speeds, the intention to produce rapid force irrespective of actual movement speed, and similarity between training and testing movement patterns evoke the greatest improvements. In contrast to expectation, current evidence indicates a between-sex difference in response to training; however, a lack of data in women prevents robust analysis, and this should be a target of future research. Of interest from a training program design perspective was that RFD improvements were greatest within the first weeks of training, with less ongoing improvement (or a reduction in RFD) with longer training, particularly when training velocity was slow or there was a lack of intent for fast force production.
Introduction:
Cancer cachexia is characterized by loss of muscle mass and function. Increased protein catabolism, inflammation, impaired anabolism, and mitochondrial function markedly contribute to the pathogenesis of this syndrome. Physical activity has been suggested as a useful tool to prevent or at least delay the onset and progression of cancer-induced muscle wasting. Two main types of exercise can be adopted, namely, resistance and endurance training. The present study is aimed to investigate the effectiveness of a combined (resistance + endurance) exercise protocol in preventing/reverting cancer-induced muscle wasting.
Methods:
Mice bearing the C26 colon carcinoma have been used as a model of cancer cachexia. They have been exposed to combined exercise training during 6 wk (4 before tumor implantation, 2 during tumor growth). Climbing a 1-m ladder inclined at 85° has been used for resistance training, while aerobic (endurance) exercise has been carried out on the same day using a motorized wheel.
Results:
In C26-bearing mice, both muscle mass and strength are improved by combined training, while just the latter increased in exercised healthy animals. Such a pattern is associated with modulations of two markers of autophagy, namely, LC3B-I/II ratio, increased in sedentary tumor hosts and reduced in exercised C26-bearing mice, and p62, steadily increased in both sedentary and trained tumor-bearing animals. Finally, combined training is not able to modify PGC-1α protein levels, but it improves succinate dehydrogenase activity, both reduced in the muscle of the C26 hosts.
Conclusion:
The data reported in the present study show that combined training improves muscle mass and function in the C26 hosts, likely modulating autophagy and improving mitochondrial function; these observations suggest that combined exercise might become part of a multimodal approach to treat cancer cachexia.
The aim of the present study is to determine the anaerobic power of men of similar age representing different sports disciplines. Professional athletes representing the following sports participated in the study: soccer (n=15, PS), martial arts (n=12, MA), weightlifting (n=15, WL), powerlifting (n=15, PL), middle- and long distance running (n=12, DR), race walking (n=14, RW), and recreational soccer (n=15, RS). After recording personal and somatic data, the subjects performed a 3-minute warm-up followed immediately by a 30 seconds cycloergometric Wingate test. The following variables of anaerobic power were calculated: total external work (TEW-KJ/30s), maximal power (Pmax-W/kg), mean power (Pmean-W/kg), fatigue index (FI-%). It was shown that the examined groups differed in body weight (F=13.560, p<0.001), body height (F=3.342, p<0.01) and BMI (F=28.868, p<0.01). There were also significant differences in the TEW range (F=5.764, p<0.001), Pmax (F=2.807, p=0.013) and FI=4.942, p<0.001) and no intergroup difference in the Pmean range. In conclusion, it should be pointed out that various types of sports training develop in the various degree different components of anaerobic power, however they develop similarly its average value.
Low-volume high-intensity interval training (HIT) appears to be an efficient and practical way to develop physical fitness.
Our objective was to estimate meta-analysed mean effects of HIT on aerobic power (maximum oxygen consumption [VO2max] in an incremental test) and sprint fitness (peak and mean power in a 30-s Wingate test).
Five databases (PubMed, MEDLINE, Scopus, BIOSIS and Web of Science) were searched for original research articles published up to January 2014. Search terms included 'high intensity', 'HIT', 'sprint', 'fitness' and 'VO2max'.
Inclusion criteria were fitness assessed pre- and post-training; training period ≥2 weeks; repetition duration 30-60 s; work/rest ratio <1.0; exercise intensity described as maximal or near maximal; adult subjects aged >18 years.
The final data set consisted of 55 estimates from 32 trials for VO2max, 23 estimates from 16 trials for peak sprint power, and 19 estimates from 12 trials for mean sprint power. Effects on fitness were analysed as percentages via log transformation. Standard errors calculated from exact p values (where reported) or imputed from errors of measurement provided appropriate weightings. Fixed effects in the meta-regression model included type of study (controlled, uncontrolled), subject characteristics (sex, training status, baseline fitness) and training parameters (number of training sessions, repetition duration, work/rest ratio). Probabilistic magnitude-based inferences for meta-analysed effects were based on standardized thresholds for small, moderate and large changes (0.2, 0.6 and 1.2, respectively) derived from between-subject standard deviations (SDs) for baseline fitness.
A mean low-volume HIT protocol (13 training sessions, 0.16 work/rest ratio) in a controlled trial produced a likely moderate improvement in the VO2max of active non-athletic males (6.2 %; 90 % confidence limits ±3.1 %), when compared with control. There were possibly moderate improvements in the VO2max of sedentary males (10.0 %; ±5.1 %) and active non-athletic females (3.6 %; ±4.3 %) and a likely small increase for sedentary females (7.3 %; ±4.8 %). The effect on the VO2max of athletic males was unclear (2.7 %; ±4.6 %). A possibly moderate additional increase was likely for subjects with a 10 mL·kg(-1)·min(-1) lower baseline VO2max (3.8 %; ±2.5 %), whereas the modifying effects of sex and difference in exercise dose were unclear. The comparison of HIT with traditional endurance training was unclear (-1.6 %; ±4.3 %). Unexplained variation between studies was 2.0 % (SD). Meta-analysed effects of HIT on Wingate peak and mean power were unclear.
Low-volume HIT produces moderate improvements in the aerobic power of active non-athletic and sedentary subjects. More studies are needed to resolve the unclear modifying effects of sex and HIT dose on aerobic power and the unclear effects on sprint fitness.
This study tested the hypothesis that chronic aerobic and resistance exercise (AE+RE) would elicit greater muscle hypertrophy than resistance exercise only (RE). Ten men (25±4 yrs) performed 5 wks unilateral knee extensor AE+RE. The opposing limb was subjected to RE. AE completed 6 hrs prior to RE, consisted of ~45 min one-legged cycle ergometry. RE comprised 4 x 7 maximal concentric-eccentric knee extensions. Various indices of in vivo knee extensor function were measured before and after training. Magnetic resonance imaging (MRI) assessed m. quadricep femoris (QF) cross-sectional area (CSA), volume, and signal intensity (SI). Biopsies obtained from m. vastus lateralis determined fiber CSA, enzyme levels and gene expression of myostatin, atrogin-1, MuRF-1, PGC-1α and VEGF. Increases (P < 0.05) in isometric strength and peak power, respectively were comparable in AE+RE (9 and 29%) and RE (11 and 24%). AE+RE showed greater increase (14%; P < 0.05) in QF volume than RE (8%). Muscle fiber CSA increased 17% after AE+RE (P < 0.05) and 9% after RE (P > 0.05). QF SI increased (12%; P < 0.05) after AE+RE, but not RE. Neither AE+RE nor RE showed altered mRNA-levels. Citrate Synthase activity increased (P < 0.05) after AE+RE. The results suggest that the increased aerobic capacity shown with AE+RE, was accompanied by a more robust increase in muscle size compared with RE. While this response was not carried over to greater improvement in muscle function, it remains that intense AE can be executed prior to RE without compromising performance outcome.
Competitive, high-class track athletes of the strength-speed events were submitted to the 10- and 30-second versions of the Wingate test to compare the values of basic variables such as maximal power, total external work, fatigue index, and chosen physiological responses. The 24 male and female athletes performed the 2 tests with a 3-day rest period between them. The results indicate that even highly trained athletes of both sexes reach higher values of maximal power in the 10-second test. Also, peak power is reached more quickly and sustained for a shorter period of time. Power decrement in the first 10 seconds is smaller in the longer version, and total external work is less. All this indicates that the rate of energy expenditure and total energy expenditure is higher for the shorter test, which suggests the need for pacing in the longer version. High postexercise heart rate and high lactic acid concentration following the 30-second Wingate test indicate a predominance of glycolytic metabolism, thus indicating that the longer version is more valuable in the evaluation of anaerobic capacity.
(C) 1999 National Strength and Conditioning Association
Impairment in strength development has been demonstrated with combined strength and endurance training as compared with strength training alone. The purpose of this study was to examine the effects of combining conventional 3 d[middle dot]wk-1 strength and endurance training on the compatibility of improving both [latin capital V with dot above]O2peak and strength performance simultaneously. Sedentary adult males, randomly assigned to one of three groups (N = 10 each), completed 10 wk of training. A strength-only (S) group performed eight weight-training exercises (4 sets/exercise, 5-7 repetitions/set), an endurance-only (E) group performed continuous cycle exercise (50 min at 70% heart rate reserve), and a combined (C) group performed the same S and E exercise in a single session. S and C groups demonstrated similar increases (P < 0.0167) in 1RM squat (23% and 22%) and bench press (18% for both groups), in maximal isometric knee extension torque (12% and 7%), in maximal vertical jump (6% and 9%), and in fat-free mass (3% and 5%). E training did not induce changes in any of these variables. [latin capital V with dot above]O2peak (ml[middle dot]kg-1min-1) increased (P < 0.01) similarity in both E (18%) and C (16%) groups. Results indicate 3 d[middle dot]wk-1 combined training can induce substantial concurrent and compatible increases in [latin capital V with dot above]O2peak and strength performance.
(C)1995The American College of Sports Medicine
Thirty-five healthy men were matched and randomly assigned to one of four training groups that performed high-intensity strength and endurance training (C; n = 9), upper body only high-intensity strength and endurance training (UC; n = 9), high-intensity endurance training (E; n = 8), or high-intensity strength training (ST; n = 9). The C and ST groups significantly increased one-repetition maximum strength for all exercises (P < 0.05). Only the C, UC, and E groups demonstrated significant increases in treadmill maximal oxygen consumption. The ST group showed significant increases in power output. Hormonal responses to treadmill exercise demonstrated a differential response to the different training programs, indicating that the underlying physiological milieu differed with the training program. Significant changes in muscle fiber areas were as follows: types I, IIa, and IIc increased in the ST group; types I and IIc decreased in the E group; type IIa increased in the C group; and there were no changes in the UC group. Significant shifts in percentage from type IIb to type IIa were observed in all training groups, with the greatest shift in the groups in which resistance trained the thigh musculature. This investigation indicates that the combination of strength and endurance training results in an attenuation of the performance improvements and physiological adaptations typical of single-mode training.
The primary objective of this investigation was to identify which components of endurance training (e.g., modality, duration, frequency) are detrimental to resistance training outcomes. A meta-analysis of 21 studies was performed with a total of 422 effect sizes (ESs). Criteria for the study included were (a) compare strength training alone to strength plus endurance training (concurrent) or to compare combinations of concurrent training; (b) the outcome measures include at least one measure of strength, power, or hypertrophy; and (c) the data necessary to calculate ESs must be included or available. The mean ES for hypertrophy for strength training was 1.23; for endurance training, it was 0.27; and for concurrent training, it was 0.85, with strength and concurrent training being significantly greater than endurance training only. The mean ES for strength development for strength training was 1.76; for endurance training, it was 0.78; and for concurrent training, it was 1.44. Strength and concurrent training was significantly greater than endurance training. The mean ES for power development for strength training only was 0.91; for endurance training, it was 0.11; and for concurrent training, it was 0.55. Significant differences were found between all the 3 groups. For moderator variables, resistance training concurrently with running, but not cycling, resulted in significant decrements in both hypertrophy and strength. Correlational analysis identified significant negative relationships between frequency (-0.26 to -0.35) and duration (-0.29 to -0.75) of endurance training for hypertrophy, strength, and power. Significant relationships (p < 0.05) between ES for decreased body fat and % maximal heart rate (r = -0.60) were also found. Our results indicate that interference effects of endurance training are a factor of the modality, frequency, and duration of the endurance training selected.
Regardless of age or gender, resistance training or provision of adequate amounts of dietary protein (PRO) or essential amino acids (EAA) can increase muscle protein synthesis (MPS) in healthy adults. Combined PRO or EAA ingestion proximal to resistance training, however, can augment the post-exercise MPS response and has been shown to elicit a greater anabolic effect than exercise plus carbohydrate. Unfortunately, chronic/adaptive response data comparing the effects of different protein sources is limited. A growing body of evidence does, however, suggest that dairy PRO, and whey in particular may: 1) stimulate the greatest rise in MPS, 2) result in greater muscle cross-sectional area when combined with chronic resistance training, and 3) at least in younger individuals, enhance exercise recovery. Therefore, this review will focus on whey protein supplementation and its effects on skeletal muscle mass when combined with heavy resistance training.
This study examined the effect of concurrent muscular strength and high-intensity running interval training on professional soccer players' explosive performances and aerobic endurance. Thirty-nine players participated in the study, where both the experimental group (EG, n = 20) and control group (CG, n = 19) participated in 8 weeks of regular soccer training, with the EG receiving additional muscular strength and high-intensity interval training twice per week throughout. Muscular strength training consisted of 4 sets of 6RM (repetition maximum) of high-pull, jump squat, bench press, back half squat, and chin-up exercises. The high-intensity interval training consisted of 16 intervals each of 15-second sprints at 120% of individual maximal aerobic speed interspersed with 15 seconds of rest. EG significantly increased (p < or = 0.05) 1RM back half squat and bench press but showed no changes in body mass. Within-subject improvement was significantly higher (p < or = 0.01) in the EG compared with the CG for vertical jump height, 10-m and 30-m sprint times, distances covered in the Yo-Yo Intermittent Recovery Test and maximal aerobic speed test, and maximal aerobic speed. High-intensity interval running can be concurrently performed with high load muscular strength training to enhance soccer players' explosive performances and aerobic endurance.
Simultaneously training for both strength and endurance results in a compromised adaptation, compared with training for either exercise mode alone. This has been variously described as the concurrent training effect or the interference effect. It now appears that the genetic and molecular mechanisms of adaptation induced by resistance- and endurance-based training are distinct, with each mode of exercise activating and (or) repressing specific subsets of genes and cellular signalling pathways. This brief review will summarize our current understanding of the molecular responses to strength and endurance training, and will examine the molecular evidence for an interference effect when concurrent training is undertaken. A better understanding of the activation and interaction of the molecular pathways in response to these different modes of exercise will permit sport scientists to develop improved training programs capable of maximizing both strength and endurance.
There are few studies that have compared different periodization methods for strength and hypertrophy. The aim of this study was to verify the effect of a 12-week strength training program with different periodization models on body composition and strength levels in women ranging from 20 to 35 years of age. Participants had a minimum of 6 months of experience in strength training, and they were divided into two groups: linear periodization (LP, n = 10) and reverse linear periodization (RLP, n = 10). Intensity was increased weekly; LP began with 12-14 maximal repetitions (RM), reaching loads of 4-6RM, and RLP began with 6-4RM and finished with 12-14RM. In all exercises, three sets were accomplished; number of repetitions and rest between sets and exercises were in accordance with weekly prescribed intensity. Training was performed 3 days per week. The evaluations were baseline evaluation (A1), after 4 weeks of training (A2), after 8 weeks (A3), after 12 weeks (A4), and after 1 week of detraining (A5). Fat mass and fat-free mass, maximum strength (bench press, lat pull-down, arm curl, and leg extension) were evaluated. There was an increase in fat-free mass and a decrease in fat mass in A4 compared with A1 only for the LP group. Both the LP and RLP groups presented significant gains in maximum strength levels in all exercises analyzed. However, for LP, the increases were greater when compared with RLP. In practical terms, LP is more effective for strength and hypertrophy as compared with RLP, and 1 week may be an adequate period for application of detraining without causing decreases in the performance of the parameters analyzed.
This study consists of two training experiments using a mechanically braked cycle ergometer. First, the effect of 6 wk of moderate-intensity endurance training (intensity: 70% of maximal oxygen uptake (VO2max), 60 min.d-1, 5 d.wk-1) on the anaerobic capacity (the maximal accumulated oxygen deficit) and VO2max was evaluated. After the training, the anaerobic capacity did not increase significantly (P > 0.10), while VO2max increased from 53 +/- 5 ml.kg-1 min-1 to 58 +/- 3 ml.kg-1.min-1 (P < 0.01) (mean +/- SD). Second, to quantify the effect of high-intensity intermittent training on energy release, seven subjects performed an intermittent training exercise 5 d.wk-1 for 6 wk. The exhaustive intermittent training consisted of seven to eight sets of 20-s exercise at an intensity of about 170% of VO2max with a 10-s rest between each bout. After the training period, VO2max increased by 7 ml.kg-1.min-1, while the anaerobic capacity increased by 28%. In conclusion, this study showed that moderate-intensity aerobic training that improves the maximal aerobic power does not change anaerobic capacity and that adequate high-intensity intermittent training may improve both anaerobic and aerobic energy supplying systems significantly, probably through imposing intensive stimuli on both systems.
Both aerobic training (AT) and resistance training (RT) may increase aerobic power (VO2peak) in the older population; however, the role of changes in the capillary supply in this response has not been evaluated. Twenty healthy men (age 65-74 yr) engaged in either 9 wk of lower body RT followed by 9 wk of AT on a cycle ergometer (RT-->AT group) or 18 wk of AT on a cycle ergometer (AT-->AT group). RT was performed three times per week and consisted of three sets of four exercises at 6-12 repetitions maximum. AT was performed three times per week for 30 min at 60-70% heart rate reserve. VO2peak was increased after both RT and AT (P < 0.05). Biopsies (vastus lateralis) revealed that the number of capillaries per fiber perimeter length was increased after both AT and RT (P < 0.05), paralleling the changes in VO2peak, whereas capillary density was increased only after AT (P < 0.01). These results, and the finding of a significant correlation between the change in capillary supply and VO2peak (r = 0.52), suggest the possibility that similar mechanisms may be involved in the increase of VO2peak after high-intensity RT and AT in the older population.
In contrast to endurance training, little research has been carried out to investigate the effects of short (< 10 s) sprint training on performance, muscle metabolism and fibre types. Nine fit male subjects performed a mean of 16 outdoor sprint running training sessions over 6 weeks. Distances sprinted were 30-80 m at 90-100% maximum speed and between 20 and 40 sprints were performed in each session. Endurance (maximal oxygen consumption; VO2max), sprint (10 m and 40 m times), sustained sprint (supramaximal treadmill run) and repeated sprint (6 x 40 m sprints, 24 s recovery between each) performance tests were performed before and after training. Muscle biopsy samples (vastus lateralis) were also taken to examine changes in metabolites, enzyme activities and fibre types. After training, significant improvements were seen in 40 m time (P < 0.01), supramaximal treadmill run time (P < 0.05), repeated sprint performance (P < 0.05) and VO2max (P < 0.01). Resting muscle concentrations of ATP and phosphocreatine did not change. Phosphorylase activity increased (P < 0.025), citrate synthase activity decreased (P < 0.01), but no significant changes were recorded in myokinase and phosphofructokinase activities. The proportion of type II muscle fibres increased significantly (P < 0.05). These results demonstrate that 6 weeks of short sprint training can improve endurance, sprint and repeated sprint ability in fit subjects. Increases in the proportion of type II muscle fibres are also possible with this type of training.
The maximal rate of rise in muscle force [rate of force development (RFD)] has important functional consequences as it determines the force that can be generated in the early phase of muscle contraction (0-200 ms). The present study examined the effect of resistance training on contractile RFD and efferent motor outflow ("neural drive") during maximal muscle contraction. Contractile RFD (slope of force-time curve), impulse (time-integrated force), electromyography (EMG) signal amplitude (mean average voltage), and rate of EMG rise (slope of EMG-time curve) were determined (1-kHz sampling rate) during maximal isometric muscle contraction (quadriceps femoris) in 15 male subjects before and after 14 wk of heavy-resistance strength training (38 sessions). Maximal isometric muscle strength [maximal voluntary contraction (MVC)] increased from 291.1 +/- 9.8 to 339.0 +/- 10.2 N. m after training. Contractile RFD determined within time intervals of 30, 50, 100, and 200 ms relative to onset of contraction increased from 1,601 +/- 117 to 2,020 +/- 119 (P < 0.05), 1,802 +/- 121 to 2,201 +/- 106 (P < 0.01), 1,543 +/- 83 to 1,806 +/- 69 (P < 0.01), and 1,141 +/- 45 to 1,363 +/- 44 N. m. s(-1) (P < 0.01), respectively. Corresponding increases were observed in contractile impulse (P < 0.01-0.05). When normalized relative to MVC, contractile RFD increased 15% after training (at zero to one-sixth MVC; P < 0.05). Furthermore, muscle EMG increased (P < 0.01-0.05) 22-143% (mean average voltage) and 41-106% (rate of EMG rise) in the early contraction phase (0-200 ms). In conclusion, increases in explosive muscle strength (contractile RFD and impulse) were observed after heavy-resistance strength training. These findings could be explained by an enhanced neural drive, as evidenced by marked increases in EMG signal amplitude and rate of EMG rise in the early phase of muscle contraction.
The purpose of this study was to investigate effects of concurrent strength and endurance training (SE) (2 plus 2 days a week) versus strength training only (S) (2 days a week) in men [SE: n=11; 38 (5) years, S: n=16; 37 (5) years] over a training period of 21 weeks. The resistance training program addressed both maximal and explosive strength components. EMG, maximal isometric force, 1 RM strength, and rate of force development (RFD) of the leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris (QF) throughout the lengths of 4/15–12/15 (L
f) of the femur, muscle fibre proportion and areas of types I, IIa, and IIb of the vastus lateralis (VL), and maximal oxygen uptake (V̇O2max) were evaluated. No changes occurred in strength during the 1-week control period, while after the 21-week training period increases of 21% (p<0.001) and 22% (p<0.001), and of 22% (p<0.001) and 21% (p<0.001) took place in the 1RM load and maximal isometric force in S and SE, respectively. Increases of 26% (p<0.05) and 29% (p<0.001) occurred in the maximum iEMG of the VL in S and SE, respectively. The CSA of the QF increased throughout the length of the QF (from 4/15 to 12/15 L
f) both in S (p<0.05–0.001) and SE (p<0.01–0.001). The mean fibre areas of types I, IIa and IIb increased after the training both in S (p<0.05 and 0.01) and SE (p<0.05 and p<0.01). S showed an increase in RFD (p<0.01), while no change occurred in SE. The average iEMG of the VL during the first 500 ms of the rapid isometric action increased (p<0.05–0.001) only in S. V̇O2max increased by 18.5% (p<0.001) in SE. The present data do not support the concept of the universal nature of the interference effect in strength development and muscle hypertrophy when strength training is performed concurrently with endurance training, and the training volume is diluted by a longer period of time with a low frequency of training. However, the present results suggest that even the low-frequency concurrent strength and endurance training leads to interference in explosive strength development mediated in part by the limitations of rapid voluntary neural activation of the trained muscles.
To compare regimens of concurrent strength and endurance training, 26 male basketball players were matched for stature, body composition, and physical activity level. Subjects completed different training programs for 7 weeks, 4 days per week. Groups were as follows: (a) the strength group (S; n = 7) did strength training; (b) the endurance group (E; n = 7) did endurance training; (c) the strength and endurance group (S + E; n = 7) combined strength and endurance training; and (d) the control group (C; n = 5) had no training. The S + E group showed greater gains in Vo(2)max than the E group did (12.9% vs. 6.8%), whereas the S group showed a decline (8.8%). Gains were noted in strength and vertical jump performance for the S + E and S groups. The S + E group had better posttraining anaerobic power than the S group did (6.2% vs. 2.9%). No strength, power, or anaerobic power gains were present for the E and C groups. We conclude that concurrent endurance and strength training is more effective in terms of improving athletic performance than are endurance and strength training apart.
The purpose of this research was to determine the effects of high intensity endurance training (ET) and resistance training (RT) alone and in combination on various military tasks. Thirty-five male soldiers were randomly assigned to one of four training groups: total body resistance training plus endurance training (RT + ET), upper body resistance training plus endurance training [UB + ET), RT only, and ET only. Training was performed 4 days per week for 12 weeks. Testing occurred before and after the 12-week training regimen. All groups significantly improved push-up performance, whereas only the RT + ET group did not improve sit-up performance. The groups that included ET significantly decreased 2-mile run time, however, only RT + ET and UB + ET showed improved loaded 2-mile run time. Leg power increased for groups that included lower body strengthening exercises (RT and RT + ET). Army Physical Fitness Test performance, loaded running, and leg power responded positively to training, however, it appears there is a high degree of specificity when concurrent training regimens are implemented.
Skeletal muscle is a malleable tissue capable of altering the type and amount of protein in response to disruptions to cellular homeostasis. The process of exercise-induced adaptation in skeletal muscle involves a multitude of signalling mechanisms initiating replication of specific DNA genetic sequences, enabling subsequent translation of the genetic message and ultimately generating a series of amino acids that form new proteins. The functional consequences of these adaptations are determined by training volume, intensity and frequency, and the half-life of the protein. Moreover, many features of the training adaptation are specific to the type of stimulus, such as the mode of exercise. Prolonged endurance training elicits a variety of metabolic and morphological changes, including mitochondrial biogenesis, fast-to-slow fibre-type transformation and substrate metabolism. In contrast, heavy resistance exercise stimulates synthesis of contractile proteins responsible for muscle hypertrophy and increases in maximal contractile force output. Concomitant with the vastly different functional outcomes induced by these diverse exercise modes, the genetic and molecular mechanisms of adaptation are distinct. With recent advances in technology, it is now possible to study the effects of various training interventions on a variety of signalling proteins and early-response genes in skeletal muscle. Although it cannot presently be claimed that such scientific endeavours have influenced the training practices of elite athletes, these new and exciting technologies have provided insight into how current training techniques result in specific muscular adaptations, and may ultimately provide clues for future and novel training methodologies. Greater knowledge of the mechanisms and interaction of exercise-induced adaptive pathways in skeletal muscle is important for our understanding of the aetiology of disease, maintenance of metabolic and functional capacity with aging, and training for athletic performance. This article highlights the effects of exercise on molecular and genetic mechanisms of training adaptation in skeletal muscle.
Twenty-six active university students were randomly allocated to resistance (R, n = 9), endurance (E, n 8), and concurrent resistance and endurance (C, n = 9) training conditions. Training was completed 3 times per week in all conditions, with endurance training preceding resistance training in the C group. Resistance training involved 4 sets of upper- and lower-body exercises with loads of 4-8 repetition maximum (RM). Each endurance training session consisted of five 5-minute bouts of incremental cycle exercise at between 40 and 100% of peak oxygen uptake (Vo(2)peak). Parameters measured prior to and following training included strength (1RM and isometric and isokinetic [1.04, 3.12, 5.20, and 8.67 rad(.)s(-1)] strength), Vo(2)peak and Wingate test performance (peak power output [PPO], average power, and relative power decline). Significant improvements in 1RM strength were observed in the R and C groups following training. Vo(2)peak significantly increased in E and C but was significantly reduced in R after training. Effect size (ES) transformations on the other dependent variables suggested that performance changes in the C group were not always similar to changes in the R or E groups. These ES data suggest that statistical power and dependent variable selection are significant issues in enhancing our insights into concurrent training. It may be necessary to assess a range of performance parameters to monitor the relative effectiveness of a particular concurrent training regimen.
This study was done to determine the accuracy of 7 equations for predicting a 1-RM from repetitions to fatigue for the bench press, squat, and deadlift. Subjects, 67 untrained college students (40 M, 27 F) who were enrolled in weight training classes, participated in four 45-min practice sessions to learn proper lifting technique and determine the amount of weight to lift for the 1-RM test. All correlation coefficients between predicted and achieved 1-RM lifts were high (r > 0.95). For the bench press, however, the average differences between achieved and predicted weights were significantly different from zero in all but 2 equations. For the squat, the average difference was significantly different from zero in all but 1 equation. All equations significantly underestimated the deadlift despite high correlations.
(C) 1997 National Strength and Conditioning Association
The purpose of the investigation was to determine whether low-intensity continuous (LSD) or high-intensity interval (INT) endurance activity prior to isokinetic strength assessment reduced torques generated 0.52 rad (30[degrees]) prior to horizontal (T30). T30 was measured at 10 contractile speeds (0.52-5.20 rad[middle dot]s-1) prior to and following the LSD and INT exercise bouts. Six males (23.2+/-3.3yrs, 74.9+/-6.8 kg, 177.6+/-5.4 cm) with a mean peak cycle ergometer oxygen consumption (PCE VO2) of 3.85 (+/-0.33) L[middle dot] min-1 completed 150 min cycling at 35% PCE VO2 in the LSD challenge. The 5 females and 3 males (20.8 +/-4.6 yrs, 63.2+/-12.0 kg, 168.8+/-8.5 cm, 2.51 +/-0.78 L[middle dot]min-1) of the INT condition completed five 5-min repetitions in which the work rate was progressively increased from 40 to 100% PCE VO2. Both the LSD and INT regimens reduced T30 at all contractile speeds. The reduction in T30 was similarly small for the LSD and INT conditions when expressed as percentage of preintervention values and effect sizes. Small, acute reductions in strength as a result of temporally proximal endurance activity may partially explain the inhibition in strength development that has followed some concurrent strength and endurance training investigations.
(C) 1993 National Strength and Conditioning Association
This study examined the effects of concurrent strength and endurance training on neuromuscular and endurance characteristics compared to strength or endurance training alone. Previously untrained men were divided into strength (S: n=16), endurance (E: n=11) or concurrent strength and endurance (SE: n=11) training groups. S and E trained 2 times and SE 2 + 2 times a week for strength and endurance during the 21-week period. Maximal unilateral isometric and bilateral concentric forces of leg muscles increased similarly in S and SE by 20-28% (p<0.01) and improvements in isometric forces were accompanied by increases (p<0.05) of maximal muscle activation. Rate of force development of isometric action (p<0.05) improved only in S. The increase in muscle cross-sectional area of the quadriceps femoris in SE (11%, p<0.001) were greater than in S (6%, p<0.001) or in E (2%, p<0.05). SE and E increased maximal cycling power (SE: 17% and E: 11%, p<0.001) and VO(2MAX) (SE: 17%, p<0.001 and E: 5%, ns.). These results suggest that the present moderate volume 21-week concurrent SE training in previously untrained men optimizes the magnitude of muscle hypertrophy, maximal strength and endurance development, but interferes explosive strength development, compared with strength or endurance training alone.
This study assessed the influence of an acute aerobic exercise bout on molecular responses to subsequent resistance exercise (RE).
Nine physically active men performed a 45-min one-legged cycle ergometry exercise and 4 × 7 maximal concentric-eccentric knee extensions for each leg 6 h later. Thus, one limb was subjected to aerobic and resistance exercise (AE+RE), and the contralateral limb to resistance exercise (RE) only. Knee extensor peak power was determined. Biopsies were obtained from the m vastus lateralis before (PRE) and 15 min (POST1) and 3 h after RE. Analysis determined glycogen content, mRNA levels (vascular endothelial growth factor, peroxisome proliferator-activated receptor-γ coactivator-1, muscle RING-finger protein-1, atrogin-1, myostatin), and phosphorylated proteins (mammalian target of rapamycin, p70S6 kinase, ribosomal protein S6, eukaryotic elongation factor 2).
Peak power was similar in AE + RE and RE. After RE, the time course of glycogen utilization and protein signaling was similar across legs. However, phosphorylation of mammalian target of rapamycin and p70S6 kinase was elevated in AE + RE versus RE (main effect, P < 0.05). Vascular endothelial growth factor and peroxisome proliferator-activated receptor-γ coactivator-1 were higher in AE + RE than in RE at PRE and POST1 (P < 0.05). Myostatin was lower in AE + RE versus RE at PRE and POST1 (P < 0.05) and downregulated after resistance exercise only. Atrogin-1 was higher in AE + RE than in RE at PRE and POST1 (P < 0.05) and decreased after RE in AE + RE. Muscle RING-finger protein-1 was similar across legs. No difference for any marker was evident 3 h after RE.
These results suggest that acute aerobic exercise alters molecular events regulating muscle protein turnover during the early recovery period from subsequent RE.
Effects of 6 mo of heavy-resistance training combined with explosive exercises on neural activation of the agonist and antagonist leg extensors, muscle cross-sectional area (CSA) of the quadriceps femoris, as well as maximal and explosive strength were examined in 10 middle-aged men (M40; 42 +/- 2 yr), 11 middle-aged women (W40; 39 +/- 3 yr), 11 elderly men (M70; 72 +/- 3 yr) and 10 elderly women (W70; 67 +/- 3 yr). Maximal and explosive strength remained unaltered during a 1-mo control period with no strength training. After the 6 mo of training, maximal isometric and dynamic leg-extension strength increased by 36 +/- 4 and 22 +/- 2% (P < 0. 001) in M40, by 36 +/- 3 and 21 +/- 3% (P < 0.001) in M70, by 66 +/- 9 and 34 +/- 4% (P < 0.001) in W40, and by 57 +/- 10 and 30 +/- 3% (P < 0.001) in W70, respectively. All groups showed large increases (P < 0.05-0.001) in the maximum integrated EMGs (iEMGs) of the agonist vastus lateralis and medialis. Significant (P < 0.05-0.001) increases occurred in the maximal rate of isometric force production and in a squat jump that were accompanied with increased (P < 0.05-0. 01) iEMGs of the leg extensors. The iEMG of the antagonist biceps femoris muscle during the maximal isometric leg extension decreased in both M70 (from 24 +/- 6 to 21 +/- 6%; P < 0.05) and in W70 (from 31 +/- 9 to 24 +/- 4%; P < 0.05) to the same level as recorded for M40 and W40. The CSA of the quadriceps femoris increased in M40 by 5% (P < 0.05), in W40 by 9% (P < 0.01), in W70 by 6% (P < 0.05), and in M70 by 2% (not significant). Great training-induced gains in maximal and explosive strength in both middle-aged and elderly subjects were accompanied by large increases in the voluntary activation of the agonists, with significant reductions in the antagonist coactivation in the elderly subjects. Because the enlargements in the muscle CSAs in both middle-aged and elderly subjects were much smaller in magnitude, neural adaptations seem to play a greater role in explaining strength and power gains during the present strength-training protocol.
The purpose of the study was to investigate sex-related differences in explosive muscular force production, as measured by electromechanical delay (EMD) and rate of force development (RFD), and to examine the physiological mechanisms responsible for any differences. The neuromuscular performance of untrained males (n = 20) and females (n = 20) was assessed during a series of isometric knee extension contractions; explosive and maximal voluntary efforts, as well as supramaximal evoked twitches and octets (eight pulses at 300 Hz). Evoked and voluntary EMD were determined from twitch and explosive contractions. The RFD was recorded over consecutive 50 ms time windows from force onset during evoked and explosive contractions, and normalized to maximal strength. Neuromuscular activity during explosive voluntary contractions was measured with EMG of the superficial knee extensors normalized to maximal M-wave. Muscle size (thickness) and muscle-tendon unit (MTU) stiffness were assessed using ultrasonic images of the vastus lateralis at rest and during ramped contractions. Males and females had similar evoked and voluntary EMD. Males were 33% stronger (P < 0.001) and their absolute RFD was 26-56% greater (all time points P < 0.05) compared with females. Muscle size (P < 0.001) and absolute MTU stiffness were also greater for males (P < 0.05). However, normalized RFD was similar for both sexes during the first 150 ms of the explosive voluntary contractions (P > 0.05). This was consistent with the similar normalized twitch and octet RFD, MTU stiffness and agonist EMG (all P > 0.05). When differences in maximal strength were accounted for, the evoked capacity of the knee extensors for explosive force production and the ability to utilize that capacity during explosive voluntary contractions was similar for males and females.
This study investigated the effect of high-intensity endurance on subsequent isoinertial and isokinetic resistance exercise. One woman and five men (mean 6 SD: age 5 20.3 6 2.5 years; body mass 5 75.1 6 10.2 kg; height 5 177.8 6 10.3 cm) performed isoinertial and isokinetic resistance exercise under control conditions (no experimental intervention) and after an acute bout of high-intensity endurance exercise. Endurance exercise consisted of five 5-minute bouts of incremental cycle exercise at between 40 and 100% of peak cycle ergometer oxygen consumption (peak V˙ O2). Isoinertial resistance exercise consisted of three sets of squats with a load of 80% of one repetition maximum. Isokinetic resistance exercise consisted of five repetitions of leg extensions performed at five different contractile speeds (1.05, 2.09, 3.14, 4.19, and 5.24 rad•s21). Significant reductions in isokinetic torque at 0.52 rad from full extension (T30) were observed after high-intensity endurance exercise. Endurance exercise also caused significant reductions in the number of isoinertial squat lifts performed. Plasma lactate values, measured before subjects performed resistance activity, were significantly higher after high intensity endurance exercise (6.16 6 2.28 mmol•L21) when compared with the control condition (0.50 6 0.45 mmol•L21). It was concluded that an acute bout of high-intensity endurance exercise may inhibit performance in a subsequent bout of resistance activity.
The picture of training that emerges is of a process that can be divided into a number of phases. In the first phase there is a rapid improvement in the ability to perform the training exercise such as lifting weights which is the result of a learning process in which the correct sequence of muscle contractions is laid down as a motor pattern in the central nervous system. This phase is associated with little or no increase in the size or strength of individual muscles. The learning process appears to be very specific in that lifting weights makes better weight lifters but not better sprinters. The second phase is an increase in the strength of individual muscles which occurs without a matching increase in the anatomical cross-section. The mechanism for this is not clear but could be a result of increased neural activation or some change in the fibre arrangement or connective tissue content. The third phase starts at a point where scientific studies usually end, at about 12 weeks when non-athletic subjects are beginning to tire of the repeated training and testing. After this point, if training continues, there is probably a slow but steady increase in both size and strength of the exercised muscles. The stimulus for these changes remains enigmatic but almost certainly involves high forces in the muscle, probably to induce some form of damage that promotes division of satellite cells and their incorporation into existing muscle fibres. Our information on the effect of long-term training comes primarily from observations on elite athletes whose physique may well be the result of genetic endowment or the use or abuse of drugs. For the athlete or patient hoping to increase muscle size by weight training the best combination of intensity, frequency and type of exercise still remains a matter of individual choice rather than a scientific certainty.
Twenty-two male and female subjects trained for 7 wk for endurance (group E), for strength (group IS), or for both strength and endurance (group C) to evaluate the effect of concurrent performance of both modes of training on the in vivo force-velocity relationship of human muscle and on aerobic power. Endurance training consisted of five 5-min sessions three times a week on cycle ergometer with a work load that approached the subject's peak cycle-ergometer O2 uptake (peak CE VO2). Strength training consisted of two 30-s sets of maximal knee extensions per day performed on an isokinetic dynamometer three times a week at a velocity of 4.19 rad X s-1. Group C performed the same training as groups IS and E, alternating days of strength and endurance training. Subjects (groups C and IS) were tested pre- and posttraining for maximal knee-extension torque at a specific joint angle (0.52 rad below horizontal) for seven specific angular velocities (0, 0.84, 1.68, 2.81, 3.35, 4.19, and 5.03 rad X s-1). Groups C and E were tested for peak CE VO2 pretraining, at 14-day intervals, and posttraining. Group IS showed significant increases in angle-specific maximal torque at velocities up to and including the training speed (4.19 rad X s-1). Group C showed increases (P less than 0.05) at velocities of 0, 0.84, and 1.68 rad X s-1 only. Peak CE VO2, when expressed in relative or absolute terms, increased (P less than 0.05) approximately 18% for both groups E and C.(ABSTRACT TRUNCATED AT 250 WORDS)
The purpose of this study was to determine how individuals adapt to a combination of strength and endurance training as compared to the adaptations produced by either strength or endurance training separately. There were three exercise groups: a strength group (S) that exercised 30--40 min . day-1, 5 days . week-1, and endurance group (E) that exercised 40 min . day-1, 6 days . week-1; and an S and E group that performed the same daily exercise regimens as the S and E groups. After 10 weeks of training, VO2max increased approx. 25% when measured during bicycle exercise and 20% when measured during treadmill exercise in both E, and S and E groups. No increase in VO2max was observed in the S group. There was a consistent rate of development of leg-strength by the S group throughout the training, whereas the E group did not show any appreciable gains in strength. The rate of strength improvement by the S and E group was similar to the S group for the first 7 weeks of training, but subsequently leveled off and declined during the 9th and 10th weeks. These findings demonstrate that simultaneously training for S and E will result in a reduced capacity to develop strength, but will not affect the magnitude of increase in VO2max.
Concurrent strength and endurance training appears to inhibit strength development when compared with strength training alone. Our understanding of the nature of this inhibition and the mechanisms responsible for it is limited at present. This is due to the difficulties associated with comparing results of studies which differ markedly in a number of design factors, including the mode, frequency, duration and intensity of training, training history of participants, scheduling of training sessions and dependent variable selection. Despite these difficulties, both chronic and acute hypotheses have been proposed to explain the phenomenon of strength inhibition during concurrent training. The chronic hypothesis contends that skeletal muscle cannot adapt metabolically or morphologically to both strength and endurance training simultaneously. This is because many adaptations at the muscle level observed in response to strength training are different from those observed after endurance training. The observation that changes in muscle fibre type and size after concurrent training are different from those observed after strength training provide some support for the chronic hypothesis. The acute hypothesis contends that residual fatigue from the endurance component of concurrent training compromises the ability to develop tension during the strength element of concurrent training. It is proposed that repeated acute reductions in the quality of strength training sessions then lead to a reduction in strength development over time. Peripheral fatigue factors such as muscle damage and glycogen depletion have been implicated as possible fatigue mechanisms associated with the acute hypothesis. Further systematic research is necessary to quantify the inhibitory effects of concurrent training on strength development and to identify different training approaches that may overcome any negative effects of concurrent training.
Fourteen professional (NRL) and 15 college-aged (SRL) rugby league players were observed during a lengthy in-season period to monitor the possible interfering effects of concurrent resistance and energy-system conditioning on maximum strength and power levels. All subjects performed concurrent training aimed at increasing strength, power, speed, and energy-system fitness, as well as skill and team practice sessions, before and during the in-season period. The SRL group significantly improved 1 repetition maximum bench press (1RM BP) strength, but not bench throw (BT Pmax) or jump squat maximum power (JS Pmax) over their 19-week in-season. The results for the NRL group remained unchanged in all tests across their 29-week in-season. The fact that no reductions in any tests for either group occurred may be due to the prioritization, sequencing, and timing of training sessions, as well as the overall periodization of the total training volume. Having athletes better conditioned to perform concurrent training may also aid in reducing the possible interfering effects of concurrent training. Correlations between changes in 1RM BP and BT Pmax suggest differences in the mechanisms to increase power between stronger, more experienced and less strong and experienced athletes.
We performed a randomized exercise training study to assess the effects of traditional Nautilus-style (TR) or superslow (SS) strength training on muscular strength, body composition, aerobic capacity, and cardiovascular endurance. Subjects were 14 healthy, sedentary women, 19-45 years of age (mean +/- SD age, 32.7 +/- 8.9 years), randomized to either the SS or TR training protocols and trained 3 times per week for 10 weeks. Measurements were taken both before and after training, which included a maximal incremental exercise test on a cycle ergometer, body composition, and 1 repetition maximum (1RM) tests on 8 Nautilus machines. Both groups increased their strength significantly on all 8 exercises, whereas the TR group increased significantly more than the SS group on bench press (34% vs. 11%), torso arm (anterior lateral pull-down) (27% vs. 12%), leg press (33% vs. 7%), leg extension (56% vs. 24%), and leg curl (40% vs. 15%). Thus, the TR group's improvement in total exercise weight lifted was significantly greater than that of the SS group after testing (39% vs. 15%). Exercise duration on the cycle ergometer and work rate significantly improved for both groups, but there was no group-by-training interaction. No significant differences were found for body composition or additional aerobic variables measured. Both strength training protocols produced a significant improvement in strength during a 10-week training period, but the TR protocol produced better gains in the absence of changes in percentage of body fat, body mass index, lean body mass, and body weight. In addition, strength training alone did not improve Vo2max, yet short-term endurance increased.
The purpose of this study was to compare linear periodization (LP) and daily undulating periodization (DUP) for strength gains. Twenty men (age = 21 +/- 2.3 years) were randomly assigned to LP (n = 10) or DUP (n = 10) groups. One repetition maximum (1RM) was recorded for bench press and leg press as a pre-, mid-, and posttest. Training involved 3 sets (bench press and leg press), 3 days per week. The LP group performed sets of 8 RM during weeks 1-4, 6 RM during weeks 4-8, and 4 RM during weeks 9-12. The DUP group altered training on a daily basis (Monday, 8 RM; Wednesday, 6 RM; Friday, 4 RM). Analysis of variance with repeated measures revealed statistically significant differences favoring the DUP group between T1 to T2 and T1 to T3. Making program alterations on a daily basis was more effective in eliciting strength gains than doing so every 4 weeks.
Adaptations of arm and thigh muscle hypertrophy to different long-term periodized resistance training programs and the influence of upper body resistance training were examined.
Eighty-five untrained women (mean age = 23.1 +/- 3.5 yr) started in one of the following groups: total-body training [TP, N = 18 (3-8 RM training range) and TH, N = 21 (8-12 RM training range)], upper-body training [UP, N = 21 (3-8 RM training range) and UH, N = 19, (8-12 RM training range)], or a control group (CON, N = 6). Training took place on three alternating days per week for 24 wk. Assessments of body composition, muscular performance, and muscle cross-sectional area (CSA) via magnetic resonance imaging (MRI) were determined pretraining (T1), and after 12 (T2) and 24 wk (T3) of training.
Arm CSA increased at T2 (approximately 11%) and T3 (approximately 6%) in all training groups and thigh CSA increased at T2 (approximately 3%) and T3 (approximately 4.5%) only in TP and TH. Squat one-repetition maximum (1 RM) increased at T2 (approximately 24%) and T3 (approximately 11.5%) only in TP and TH and all training groups increased 1 RM bench press at T2 (approximately 16.5%) and T3 (approximately 12.4%). Peak power produced during loaded jump squats increased from T1 to T3 only in TP (12%) and TH (7%). Peak power during the ballistic bench press increased at T2 only in TP and increased from T1 to T3 in all training groups.
Training specificity was supported (as sole upper-body training did not influence lower-body musculature) along with the inclusion of heavier loading ranges in a periodized resistance-training program. This may be advantageous in a total conditioning program directed at development of muscle tissue mass in young women.
The specificity of training principle predicts that combining resistance and endurance training (concurrent training) could interfere with the maximum development of strength and endurance capacity that results from either type of training alone.
To determine whether endurance and resistance training performed concurrently produces different performance and physiologic responses compared with each type of training alone.
Untrained male volunteers were randomly assigned to one of three groups: endurance training (ET, N = 12); resistance training (RT, N = 13); and concurrent training (CT, N = 16). The following measurements were made on all subjects before and after 12 wk of training: weight, percent body fat, peak oxygen consumption (VO(2peak)), isokinetic peak torque and average power produced during single-leg flexion and extension at 60 and 180 degrees.s, one-repetition maximum (1RM) leg press, 1RM bench press, vertical jump height, and calculated jump power.
Weight and lean body mass (LBM) increased significantly in the RT and CT groups (P < 0.05). Percent body fat was significantly decreased in the ET and CT groups. VO(2peak) was significantly improved only in the ET group. Peak torque during flexion and extension at 180 degrees.s(-1) increased in the RT group. Improvements in 1RM leg press and bench press were significant in all groups, but were significantly greater in the RT and CT compared to the ET group. Jump power improved significantly only in the RT group, and no group showed a significant change in vertical jump height.
Concurrent training performed by young, healthy men does not interfere with strength development, but may hinder development of maximal aerobic capacity.
In order to improve the applicability of research to exercise professionals, it is suggested that researchers analyze and report data in intervention studies that can be interpreted in relation to other studies. The effect size and proposed scale for determining the magnitude of the treatment effect can assist strength and conditioning professionals in interpreting and applying the findings of the strength training studies.
The effects of a 16-week training period (2 days per week) of resistance training alone (upper- and lower-body extremity exercises) (S), endurance training alone (cycling exercise) (E), or combined resistance (once weekly) and endurance (once weekly) training (SE) on muscle mass, maximal strength (1RM) and power of the leg and arm extensor muscles, maximal workload (W
max) and submaximal blood lactate accumulation by using an incremental cycling test were examined in middle-aged men [S, n=11, 43 (2) years; E, n=10, 42 (2) years; SE, n=10, 41 (3) years]. During the early phase of training (from week 0 to week 8), the increase 1RM leg strength was similar in both S (22%) and SE (24%) groups, while the increase at week 16 in S (45%) was larger (P<0.05) than that recorded in SE (37%). During the 16-week training period, the increases in power of the leg extensors at 30% and 45% of 1RM were similar in all groups tested. However, the increases in leg power at the loads of 60% and 70% of 1RM at week 16 in S and SE were larger (P<0.05) than those recorded in E, and the increase in power of the arm extensors was larger (P<0.05) in S than in SE (P<0.05) and E (n.s.). No significant differences were observed in the magnitude of the increases in W
max between E (14%), SE (12%) and E (10%) during the 16-week training period. During the last 8 weeks of training, the increases in W
max in E and SE were greater (P<0.05–0.01) than that observed in S (n.s.). No significant differences between the groups were observed in the training-induced changes in submaximal blood lactate accumulation. Significant decreases (P<0.05–0.01) in average heart rate were observed after 16 weeks of training in 150 W and 180 W in SE and E, whereas no changes were recorded in S. The data indicate that low-frequency combined training of the leg extensors in previously untrained middle-aged men results in a lower maximal leg strength development only after prolonged training, but does not necessarily affect the development of leg muscle power and cardiovascular fitness recorded in the cycling test when compared with either mode of training alone.
The present study compared the effects of aerobic endurance training at different intensities and with different methods matched for total work and frequency. Responses in maximal oxygen uptake (VO2max), stroke volume of the heart (SV), blood volume, lactate threshold (LT), and running economy (CR) were examined.
Forty healthy, nonsmoking, moderately trained male subjects were randomly assigned to one of four groups:1) long slow distance (70% maximal heart rate; HRmax); 2)lactate threshold (85% HRmax); 3) 15/15 interval running (15 s of running at 90-95% HRmax followed by 15 s of active resting at 70% HRmax); and 4) 4 x 4 min of interval running (4 min of running at 90-95% HRmax followed by 3 min of active resting at 70%HRmax). All four training protocols resulted in similar total oxygen consumption and were performed 3 d.wk for 8 wk.
High-intensity aerobic interval training resulted in significantly increased VO2max compared with long slow distance and lactate-threshold training intensities (P<0.01). The percentage increases for the 15/15 and 4 x 4 min groups were 5.5 and 7.2%, respectively, reflecting increases in V O2max from 60.5 to 64.4 mL x kg(-1) x min(-1) and 55.5 to 60.4 mL x kg(-1) x min(-1). SV increased significantly by approximately 10% after interval training (P<0.05).
: High-aerobic intensity endurance interval training is significantly more effective than performing the same total work at either lactate threshold or at 70% HRmax, in improving VO2max. The changes in VO2max correspond with changes in SV, indicating a close link between the two.
Review effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein
- Hulmi
Concurrent strength and endurance training: A review
- Leveritt