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Torque vs percentage increase in cross-sectional area (CSA) per day of the quadriceps during accommodating concentric and/or eccentric training (number of study groups = 21). MVIA = maximal voluntary isometric action.  

Torque vs percentage increase in cross-sectional area (CSA) per day of the quadriceps during accommodating concentric and/or eccentric training (number of study groups = 21). MVIA = maximal voluntary isometric action.  

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Strength training is an important component in sports training and rehabilitation. Quantification of the dose-response relationships between training variables and the outcome is fundamental for the proper prescription of resistance training. The purpose of this comprehensive review was to identify dose-response relationships for the development of...

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... Resistance training frequencies of three times per week seemed to enhance concomitant improvements in muscle strength and femur/hip BMD compared with two times per week. Previous reviews and original studies have reported that higher training frequencies increase muscle cross-sectional area [78] and strength [79][80][81], although these effects are minimized when equated for weekly training volume [79,80]. In terms of the bone response, higher training frequencies seem to facilitate BMD improvements following completion of weight-bearing/impact-loading programs [82,83], but have less effect following resistance training programs [65,84], likely contributing to the wide CIs reported for the frequency effect on femur/hip BMD. ...
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Background Older adults experience considerable muscle and bone loss that are closely interconnected. The efficacy of progressive resistance training programs to concurrently reverse/slow the age-related decline in muscle strength and bone mineral density (BMD) in older adults remains unclear. Objectives We aimed to quantify concomitant changes in lower-body muscle strength and BMD in older adults following a progressive resistance training program and to determine how these changes are influenced by mode (resistance only vs. combined resistance and weight-bearing exercises), frequency, volume, load, and program length. Methods MEDLINE/PubMed and Embase databases were searched for articles published in English before 1 June, 2021. Randomized controlled trials reporting changes in leg press or knee extension one repetition maximum and femur/hip or lumbar spine BMD following progressive resistance training in men and/or women ≥ 65 years of age were included. A random-effects meta-analysis and meta-regression determined the effects of resistance training and the individual training characteristics on the percent change (Δ%) in muscle strength (standardized mean difference) and BMD (mean difference). The quality of the evidence was assessed using the Cochrane risk-of-bias tool (version 2.0) and Grading of Recommendation, Assessment, Development, and Evaluation (GRADE) criteria. Results Seven hundred and eighty studies were identified and 14 were included. Progressive resistance training increased muscle strength (Δ standardized mean difference = 1.1%; 95% confidence interval 0.73, 1.47; p ≤ 0.001) and femur/hip BMD (Δ mean difference = 2.77%; 95% confidence interval 0.44, 5.10; p = 0.02), but not BMD of the lumbar spine (Δ mean difference = 1.60%; 95% confidence interval − 1.44, 4.63; p = 0.30). The certainty for improvement was greater for muscle strength compared with BMD, evidenced by less heterogeneity (I2 = 78.1% vs 98.6%) and a higher overall quality of evidence. No training characteristic significantly affected both outcomes (p > 0.05), although concomitant increases in strength and BMD were favored by higher training frequencies, increases in strength were favored by resistance only and higher volumes, and increases in BMD were favored by combined resistance plus weight-bearing exercises, lower volumes, and higher loads. Conclusions Progressive resistance training programs concomitantly increase lower-limb muscle strength and femur/hip bone mineral density in older adults, with greater certainty for strength improvement. Thus, to maximize the efficacy of progressive resistance training programs to concurrently prevent muscle and bone loss in older adults, it is recommended to incorporate training characteristics more likely to improve BMD.
... For example, in 24 of the included studies [17-19, 38, 53-58, 60, 62-67, 69-74, 76], weekly TMT sessions were performed in addition to regular training. Potentially, this un-matched supplemental training volume could provide an additional stimulus to induce neurological and morphological adaptations, favoring the TMT groups [26,27,78,79]. ...
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Background The role of trunk muscle training (TMT) for physical fitness (e.g., muscle power) and sport-specific performance measures (e.g., swimming time) in athletic populations has been extensively examined over the last decades. However, a recent systematic review and meta-analysis on the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes is lacking. Objective To aggregate the effects of TMT on measures of physical fitness and sport-specific performance in young and adult athletes and identify potential subject-related moderator variables (e.g., age, sex, expertise level) and training-related programming parameters (e.g., frequency, study length, session duration, and number of training sessions) for TMT effects. Data Sources A systematic literature search was conducted with PubMed, Web of Science, and SPORTDiscus, with no date restrictions, up to June 2021. Study Eligibility Criteria Only controlled trials with baseline and follow-up measures were included if they examined the effects of TMT on at least one measure of physical fitness (e.g., maximal muscle strength, change-of-direction speed (CODS)/agility, linear sprint speed) and sport-specific performance (e.g., throwing velocity, swimming time) in young or adult competitive athletes at a regional, national, or international level. The expertise level was classified as either elite (competing at national and/or international level) or regional (i.e., recreational and sub-elite). Study Appraisal and Synthesis Methods The methodological quality of TMT studies was assessed using the Physiotherapy Evidence Database (PEDro) scale. A random-effects model was used to calculate weighted standardized mean differences (SMDs) between intervention and active control groups. Additionally, univariate sub-group analyses were independently computed for subject-related moderator variables and training-related programming parameters. Results Overall, 31 studies with 693 participants aged 11–37 years were eligible for inclusion. The methodological quality of the included studies was 5 on the PEDro scale. In terms of physical fitness, there were significant, small-to-large effects of TMT on maximal muscle strength (SMD = 0.39), local muscular endurance (SMD = 1.29), lower limb muscle power (SMD = 0.30), linear sprint speed (SMD = 0.66), and CODS/agility (SMD = 0.70). Furthermore, a significant and moderate TMT effect was found for sport-specific performance (SMD = 0.64). Univariate sub-group analyses for subject-related moderator variables revealed significant effects of age on CODS/agility ( p = 0.04), with significantly large effects for children (SMD = 1.53, p = 0.002). Further, there was a significant effect of number of training sessions on muscle power and linear sprint speed ( p ≤ 0.03), with significant, small-to-large effects of TMT for > 18 sessions compared to ≤ 18 sessions (0.45 ≤ SMD ≤ 0.84, p ≤ 0.003). Additionally, session duration significantly modulated TMT effects on linear sprint speed, CODS/agility, and sport-specific performance ( p ≤ 0.05). TMT with session durations ≤ 30 min resulted in significant, large effects on linear sprint speed and CODS/agility (1.66 ≤ SMD ≤ 2.42, p ≤ 0.002), whereas session durations > 30 min resulted in significant, large effects on sport-specific performance (SMD = 1.22, p = 0.008). Conclusions Our findings indicate that TMT is an effective means to improve selected measures of physical fitness and sport-specific performance in young and adult athletes. Independent sub-group analyses suggest that TMT has the potential to improve CODS/agility, but only in children. Additionally, more (> 18) and/or shorter duration (≤ 30 min) TMT sessions appear to be more effective for improving lower limb muscle power, linear sprint speed, and CODS/agility in young or adult competitive athletes.
... increase in vastus lateralis CSA) (Earp et al., 2015) compared with smaller gains following two weekly sessions (14% increase in thigh muscle volume) (Fathi et al., 2019). This is in agreement with the literature about traditional resistance training (Wernbom et al., 2007;Schoenfeld et al., 2019;Schoenfeld et al., 2021). More specifically, in a systematic review with meta-analysis of the effects of traditional resistance training frequency on skeletal muscle hypertrophy in healthy individuals, Schoenfeld et al. (2019) reported a slightly larger effect of higher compared with lower frequencies of training on hypertrophic outcomes when training volume was not equated between conditions. ...
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Objective: To examine the effect of plyometric jump training on skeletal muscle hypertrophy in healthy individuals. Methods: A systematic literature search was conducted in the databases PubMed, SPORTDiscus, Web of Science, and Cochrane Library up to September 2021. Results: Fifteen studies met the inclusion criteria. The main overall finding (44 effect sizes across 15 clusters median = 2, range = 1–15 effects per cluster) indicated that plyometric jump training had small to moderate effects [standardised mean difference (SMD) = 0.47 (95% CIs = 0.23–0.71); p < 0.001] on skeletal muscle hypertrophy. Subgroup analyses for training experience revealed trivial to large effects in non-athletes [SMD = 0.55 (95% CIs = 0.18–0.93); p = 0.007] and trivial to moderate effects in athletes [SMD = 0.33 (95% CIs = 0.16–0.51); p = 0.001]. Regarding muscle groups, results showed moderate effects for the knee extensors [SMD = 0.72 (95% CIs = 0.66–0.78), p < 0.001] and equivocal effects for the plantar flexors [SMD = 0.65 (95% CIs = −0.25–1.55); p = 0.143]. As to the assessment methods of skeletal muscle hypertrophy, findings indicated trivial to small effects for prediction equations [SMD = 0.29 (95% CIs = 0.16–0.42); p < 0.001] and moderate-to-large effects for ultrasound imaging [SMD = 0.74 (95% CIs = 0.59–0.89); p < 0.001]. Meta-regression analysis indicated that the weekly session frequency moderates the effect of plyometric jump training on skeletal muscle hypertrophy, with a higher weekly session frequency inducing larger hypertrophic gains [β = 0.3233 (95% CIs = 0.2041–0.4425); p < 0.001]. We found no clear evidence that age, sex, total training period, single session duration, or the number of jumps per week moderate the effect of plyometric jump training on skeletal muscle hypertrophy [β = −0.0133 to 0.0433 (95% CIs = −0.0387 to 0.1215); p = 0.101–0.751]. Conclusion: Plyometric jump training can induce skeletal muscle hypertrophy, regardless of age and sex. There is evidence for relatively larger effects in non-athletes compared with athletes. Further, the weekly session frequency seems to moderate the effect of plyometric jump training on skeletal muscle hypertrophy, whereby more frequent weekly plyometric jump training sessions elicit larger hypertrophic adaptations.
... Volume is commonly defined as the total amount of work performed (Schoenfeld and Grgic, 2017) and can be expressed as the total number of sets/repetition per exercise (Wernbom et al., 2007;Schoenfeld et al., 2017a) or the total number of repetitions multiplied by the amount of weight used in an exercise across sets (Schoenfeld et al., 2016b). This variable has received a great deal of attention with respect to enhancing muscle hypertrophy (Schoenfeld and Grgic, 2017), since it has been traditionally assumed that prescribing high-volume during resistance training programs will produce greater gains in muscle mass (McCall et al., 1999). ...
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This umbrella review aimed to analyze the different variables of resistance training and their effect on hypertrophy, and to provide practical recommendations for the prescription of resistance training programs to maximize hypertrophy responses. A systematic research was conducted through of PubMed/MEDLINE, SPORTDiscus and Web of Science following the preferred reporting items for systematic reviews and meta-analyses statement guidelines. A total of 52 meta-analyses were found, of which 14 met the inclusion criteria. These studies were published between 2009 and 2020 and comprised 178 primary studies corresponding to 4784 participants. Following a methodological quality analysis, nine meta-analyses were categorized as high quality, presenting values of 81-88%. The remaining meta-analyses were rated as moderate quality, with values between 63-75%. Based on this umbrella review, we can state that at least 10 sets per week per muscle group is optimal, that eccentric contractions seem important, very slow repetitions (≥10s) should be avoided, and that blood flow restriction might be beneficial for some individuals. In addition, other variables as, exercise order, time of the day and type of periodization appear not to directly influence the magnitude of muscle mass gains. These findings provide valuable information for the design and configuration of the resistance training program with the aim of optimizing muscle hypertrophy.
... A factor that must be considered is that variables, such as intensity, volume and the principle of overload, must be controlled to achieve exercise goals [39]. The principle of overload is essential to challenge the individual in order for occur training adaptation. ...
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Information about comparing the effectiveness of exercise methods on management of disk herniation is limited. The aim of this study was to compare the effect of two programs of suspension and core stability exercises on some electromyography (EMG) coordinates, pain and range of motion of patients with disk herniation. Thirty-two men with disk herniation participated in this clinical trial study which was randomly divided into three groups of suspension exercises (n: 12, age: 34.25 ± 8.81, BMI: 24.01 ± 2.7), core stability exercises (n: 10, age: 35 ± 10.3, BMI: 25 ± 2.27) and control (n: 10, age: 34.4 ± 6.67, BMI: 23.76 ± 1.45). Electrical activity of rectus abdominis, internal and external oblique and erector spinae muscles was masured by superficial EMG, back pain by McGill Pain Questionnaire and range of motion by Modified Schober test, one day before and immediately after of intervention period. The experimental groups performed an 8-week training period while the control group was only followed up. Data were analyzed using paired sample t test and analysis of covariance test and statistical significance was set at 0.05. Suspension group showed significant improvement in EMG of rectus abdominis, internal and external oblique muscles (respectively, p = 0.030, p = 0.017, p = 0.022) and pain (p = 0.001) compared to core stability group; but there was no significant difference between two groups in EMG of erector spinae muscle and range of motion. Changes in both training groups were significant in all variables compared to control groups (p ˂ 0.05). Our findings showed that although both exercises were effective in patients with lumbar disk herniation, but the effectiveness of suspension exercises in increasing muscle activation and reducing pain was more pronounced than core stability exercises. Iranian Registry of Clinical Trials (IRCT): IRCT20191016045136N1.
... Increases of ~ 20% in the present study may be a little surprising considering that power training typically does not induce significant increases in muscle mass (Häkkinen et al. 1990). Such improvement over 15 training sessions (an average of ~ 0.32% per day) is higher than the average increases reported in the literature (Wernbom et al. 2007) and is larger than the 11-13% increase over 10 weeks of training we observed in a previous study in trained men using the same ultrasound methods (Walker et al. 2016). This may be reflective of the subjects' more limited experience in resistance training than, e.g., chronic resistance trainers of previous studies (e.g., Ahtiainen et al. 2003;Pareja-Blanco et al. 2017;Walker et al. 2016). ...
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Purpose Men and women typically display different neuromuscular characteristics, force–velocity relationships, and differing strength deficit (upper vs. lower body). Thus, it is not clear how previous recommendations for training with velocity-loss resistance training based on data in men will apply to women. This study examined the inter-sex differences in neuromuscular adaptations using 20% and 40% velocity-loss protocols in back squat and bench press exercises. Methods The present study employed an 8-week intervention (2 × week) comparing 20% vs. 40% velocity-loss resistance training in the back squat and bench press exercises in young men and women (~ 26 years). Maximum strength (1-RM) and submaximal-load mean propulsive velocity (MPV) for low- and high-velocity lifts in squat and bench press, countermovement jump and vastus lateralis cross-sectional area were measured at pre-, mid-, and post-training. Surface EMG of quadriceps measured muscle activity during performance tests. Results All groups increased 1-RM strength in squat and bench press exercises, as well as MPV using submaximal loads and countermovement jump height ( P < 0.05). No statistically significant between-group differences were observed, but higher magnitudes following 40% velocity loss in 1-RM ( g = 0.60) and in low- ( g = 1.42) and high-velocity ( g = 0.98) lifts occurred in women. Training-induced improvements were accompanied by increases in surface EMG amplitude and vastus lateralis cross-sectional area. Conclusion Similar increases in strength and power performance were observed in men and women over 8 weeks of velocity-based resistance training. However, some results suggest that strength and power gains favor using 40% rather than 20% velocity loss in women.
... The number of sets, the total number of repetitions, the total duration of work and the total work are used to estimate the amount of training in previous studies. 123 The amount of training is commonly described as the product of the number of repetitions × number of sets × intensity load. 124 Schoenfeld et al studied the increase in strength and muscle mass after different volumes of training. ...
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Sarcopenia, an age-related disease characterized by loss of muscle strength and muscle mass, has attracted the attention of medical experts due to its severe morbidity, low living quality, high expenditure of health care, and mortality. Traditionally, persistent aerobic exercise (PAE) is considered as a valid way to attenuate muscular atrophy. However, nowadays, high intensity interval training (HIIT) has emerged as a more effective and time-efficient method to replace traditional exercise modes. HIIT displays comprehensive effects on exercise capacity and skeletal muscle metabolism, and it provides a time-out for the recovery of cardiopulmonary and muscular functions without causing severe adverse effects. Studies demonstrated that compared with PAE, HIIT showed similar or even higher effects in improving muscle strength, enhancing physical performances and increasing muscle mass of elder people. Therefore, HIIT might become a promising way to cope with the age-related loss of muscle mass and muscle function. However, it is worth mentioning that no study of HIIT was conducted directly on sarcopenia patients, which is attributed to the suspicious of safety and validity. In this review, we will assess the effects of different training parameters on muscle and sarcopenia, summarize previous papers which compared the effects of HIIT and PAE in improving muscle quality and function, and evaluate the potential of HIIT to replace the status of PAE in treating old people with muscle atrophy and low modality; and point out drawbacks of temporary experiments. Our aim is to discuss the feasibility of HIIT to treat sarcopenia and provide a reference for clinical scientists who want to utilize HIIT as a new way to cope with sarcopenia.
... To respond to the objective of the present study and considering a large amount of information available regarding the prescription of strength training, it was decided to adopt the training standard described by scientific studies with international recognition for each strength training variable, as described in chart II. [12]; Krieger [13]; Bird et al. [15]; Schoenfeld et al. [16]; Perterson et al. [21]; Schoenfeld et al. [23]; Kraemer and Ratamess [24]; Wernbom et al. [26]; Grgic et al. [27]; Bottaro et al. [28]; Hill-Haas et al. [29] Procedures All participants were instructed to answer all questions in the questionnaire, indicating only one of the options and, in case of doubt, when not solved, choose the option "Prefer not to answer (P.N.A). The collection was carried out in predetermined dates and times, during the intervals of the specialization classes and under the supervision of the researcher responsible for the study. ...
... It was expected that the rest interval would also show an agreement greater than 70%, since the adequate rest interval is essential for the good development of muscle hypertrophy. Results indicate that intervals longer than 60 seconds allow the energetic substrates to be adequately replaced in the muscle in action [1,12,[27][28][29][30] and shorter intervals can generate early fatigue and impair the performance of subsequent series and not allow significant gains in hypertrophy [29,30]. However, in the present study, these standards were adopted by less than 40% of professionals. ...
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How to cite: Cantieri FP, Arruda GA, Coledam DHC, Gomes AC, Aranha ACM, Barros MVG, et al. Strength training: the agreement between methodological standards and prescription by fitness professionals. Rev Bras Fisiol Exerc 2022;21(1):15-25. https://doi. ABSTRACT Introduction: The scientific advances have resulted in proposed methodologic standards to assist the prescription of physical exercise, but it is not clear whether there is a practical application of these standards by fitness professionals. Objective: To analyze the agreement between the methodologic standard for strength training and the methodology used by the fitness professionals. Methods: 461 professionals (men = 68.1%), aged 31.3 (± 6.8) years old, from the city of Londrina/PR and São Paulo/SP participated in the study, who filled out a questionaire containing 16 objective questions about strength training methodology. The Binomial test (cutoffs: 50% and 70%) was used for statistical analysis (p < 0.05). Results: Agreement significantly greater than 70% was obtained for 37.5% of the questions when considering agreement greater than 50%, plus 12.5% of the questtions were added. Agreements significantly less than 50% were identified for the number of repetitions for local muscle endurance (33.5%), load percentage for muscle power (39.5%), as well as for the rest interval for local muscle endurance (19.3%), hypertrophy (33.8%) and muscle power (20.3%). Conclusion: In general, the prescriptions indicated by fitness professionals had low agreement with the analyzed methodologic standards. RESUMO Introdução: Avanços científicos resultaram em padrões metodológicos propostos para auxiliar na prescri-ção do exercício físico, porém ainda não está claro se há aplicação prática de tais padrões por profissionais do fitness. Objetivo: Analisar a concordância entre padrões metodológicos para treinamento de força muscular e a metodologia utilizada por profissionais que atuam na área do fitness. Métodos: Participa-ram do estudo 461 profissionais (homens = 68,1%) com média de 31,3 (± 6,8) anos da cidade de Londrina/ PR e São Paulo/SP, que preencheram um questionário contendo 16 questões objetivas sobre metodologia do treinamento de força. O teste Binomial (cutoffs: 50% e 70%) foi utilizado para as análises estatísticas (p < 0,05). Resultados: Concordância significativamente maior que 70% foi obtida para 37,5% das questões. Ao considerar concordância maior que 50% mais 12,5% das questões foram adicionadas. Concordâncias significativamente inferiores a 50% foram identificadas para o número de repetições para a resistência muscular localizada (33,5%), percentual de carga para potência (39,5%), bem como para o intervalo de re-cuperação para resistência muscular localizada (19,3%), hipertrofia (33,8%) e potência (20,3%). Conclusão: A prescrição apontada pelos profissionais que atuam com fitness em geral apresentou baixa concordância com os padrões metodológicos analisados. Palavras-chave: treinamento resistido; exercício; diretrizes práticas; aptidão física; saúde.
... Those findings were not reported previously and may be useful to evaluate athletes during weight-lifting training and rehabilitation. Previous study demonstrated that an increase in the cross-sectional area of upper arm muscles, including PM, of 0.20% per day is expected following approximately 3 months of training, mainly 2-3 sessions per week [18]. Regarding greater Hum-CSA, the authors consider that this may be due to chronic mechanical overload as seen in male tennis players [19], although this finding may not be generalized and could be better explored in studies including conventional dualenergy X-ray absorptiometry (DXA)-based bone density measurements that evaluations the effects of exercise on bone. ...
Article
Objective: To evaluate magnetic resonance imaging (MRI) features of the contralateral side in weightlifting athletes with pectoralis major (PM) tears. We hypothesized that MRI of the non-injured side may present increased pectoralis major tendon (PMT) length and thickness and greater pectoralis major muscle (PMM) volume and cross-sectional area when compared with the control group. Methods: We retrospectively identified MRI cases with unilateral PM injury and reviewed imaging findings of the contralateral side. Also, we evaluated MRI from ten asymptomatic control weightlifting athletes, with PM imaging from both sides. Two musculoskeletal radiologists independently reviewed MRI and measured PMT length, PMT thickness, PMM volume (PMM-vol) and PMM cross-sectional area (PMM-CSA), as well as humeral shaft cross-sectional area (Hum-CSA) and the ratio between PMM-CSA and Hum-CSA (PMM-CSA/Hum-CSA). Data were compared between the non-injured side and controls. The MRI protocol from both groups was the same and included T1 FSE and T2 FATSAT axial, coronal, and sagittal images, one side at a time. Results: We identified 36 male subjects with unilateral PM injury with mean age 35.7 ± 8 years and 10 age- and gender-matched controls (p = 0.45). A total of 36 PM MRI with non-injured PM and 20 PM MRI studies were included in this study. PMT length and PMT thickness were significantly higher in contralateral PM injury versus control subjects (both P < 0.001). Also, PM-CSA and Hum-CSA were greater in the contralateral PM injury group (P = 0.032 and P < 0.001, respectively). PMT thickness > 2.95 mm had 80.6% sensitivity and 90.0% specificity to differentiate the non-injured PM group from controls. Conclusion: Non-injured side MR imaging of patients with previous contralateral PM lesion demonstrates greater PMT thickness and length as well as PM-CSA and Hum-CSA than controls.
... As athletes are closer to their maximum potential, programming implies a more precise manipulation, both in type and magnitude, of training variables (Cormier et al., 2020). Within resistance training, the variables most studied in terms 50 of variations are training intensity and training volume, as they highly influence muscular and neural adaptations (Peterson et al., 2005;Wernbom et al., 2007). ...
Article
Background: A main goal of programming is to structure the optimal variations in training factors to optimize athletes' adaptations. Nevertheless, it remains unknown the optimal programming model leading to greater neuromuscular adaptations. Purpose: The aim of the present study was to assess the influence of three different magnitudes of variability within resistance training programs on performance adaptations. Methods: Forty participants were assigned to three different groups differing in the frequency of change in training contents: a weekly model (WM; n = 12), a daily model (DM; n= 14), and a session model (SM; n = 14). The training intervention lasted for six weeks, performing two sessions per week of back-squat exercise. Total training load (volume and intensity) of the six-week intervention was equated for all groups. Maximum dynamic strength (1RM) in the back-squat, countermovement (CMJ) and squat jump (SJ) were measured pre- and post-training intervention. Results: All groups showed significant increases (p< .05) in 1RM, with the SM showing greater increases than the WM (20.5 vs 13.6%; p= .022). Although not reaching statistical significance, the magnitude of the increases in CMJ tended to be greater for DM and SM group (9.5% and 8.1%, respectively,) than in the WM (4.4%). All groups showed similar increases in the SJ (7.7-9.9%). Conclusions: The results of the present study suggest that the use of more frequent stimuli variations within resistance training programming is a key factor to achieve concomitant increases in strength and jumping performance.