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Abstract

To determine the effect of circadian rhythm on neuromuscular responses and kinematics related to physical tennis performance, after a standardised warm-up, 13 highly competitive male tennis players were tested twice for serve velocity/accuracy (SVA), countermovement vertical jump (CMJ), isometric handgrip strength (IS), agility T-test (AGIL) and a 10-m sprint (10-m RUN). In a randomised, counter-balance order, tennis players underwent the test battery twice, either in the morning (i.e., AM; 9:00 h) and in the afternoon (i.e., PM; 16:30 h). Paired t-tests were used to analyse differences due to time-of-day in performance variables. Comparison of morning versus afternoon testing revealed that SVA (168.5 ± 6.5 vs. 175.2 ± 6.1 km · h⁻¹; P = 0.003; effect size [ES] = 1.07), CMJ (32.2 ± 0.9 vs. 33.7 ± 1.1 cm; P = 0.018; ES = 1.46), AGIL (10.14 ± 0.1 vs. 9.91 ± 0.2 s; P = 0.007; ES = 1.23) and 10-m RUN time (1.74 ± 0.1 vs. 1.69 ± 0.1 s; P = 0.021; ES = 0.67) were significantly blunted during the morning testing. However, IS was not affected by time-of-day (P = 0.891). Thus, tennis performance may be reduced when competing in the morning in comparison to early evening. Therefore, coaches and tennis players should focus on schedule the SVA, power, speed and agility training sessions in the afternoon.

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... 6,7 Some individuals manifest being more energetic at a specific time of the day and such individual variations in circadian rhythms are described as chronotypes. [8][9][10] Based on chronotypes, individuals are classified as morning, evening, or neither chronotype. 11 The morning chronotype wakes up and goes to bed early, and their mental and physical performance is usually better in the first part of the day; whereas the evening chronotype gets up and goes to bed late and tends to show better mental or physical performance in the afternoon or evening. ...
... 9,12,13 Athletic performance is affected by circadian rhythm as well as biological, biochemical, physiological, and psychological variables. 10,[14][15][16][17][18][19][20] It has also been generally accepted that optimal athletic performance occurs during late afternoon-early evening rather than in the morning. 9,[18][19][21][22][23] Moreover, daily variations in performance can be influenced by several factors such as sleep-wake patterns; core temperature and hormone rhythms; sleep inertia; age; fatigue perception; somatosensory inputs; chronotypes; etc. 14,17 Diurnal variations in physical performance have been partly attributed to natural fluctuations in core body temperature. ...
... In these studies, diurnal variations were explained by body temperature peaking in the late afternoon. 4,8,10,[14][15][16]20,22,27 Reilly et al. reported that the circadian rhythm of core temper-ature is often used as a marker of the body clock due to its strong endogenous component. 23 Drust et al. also argued that many measures of physical performance display circadian rhythms closely in phase with body temperature variations. ...
... Participants performed a isometric handgrip strength test with 0 degrees of shoulders flexion, 0 degrees of elbow flexion and the forearm and hand in a neutral position, as previously reported in other studies (Lopez-Samanes et al. 2017). Two maximum isometric voluntary contractions were measured from the dominant and non-dominant hand using a calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan). ...
... To our knowledge, no study has examined the time-of-day effect on this particular but essential aspect of volleyball performance that is particularly important for hitters volleyball players (Duncan et al. 2006). However, our data are in agreement with previous studies in other intermittent sports that have reported similar improvements evening versus morning in specific hitting tests (4.0-5.4%) of different sport modalities that involve overhead strokes such as serve velocity in tennis (Lopez-Samanes et al. 2017) or throwing velocity in handball (Mhenni et al. 2017). ...
... However, our data are controversial with other studies in team or individual male sports that reported improvements in jump capacity in the evening compared with the morning conditions (i.e., 4.5-9.8%) (Lopez-Samanes et al. 2017;Pavlovic et al. 2018). Thus, players' sex, competition level or experience could be some of the variables that explain the lack of statistically significant effects caused by the two timeof-day protocols used in female semi-professional volleyball players. ...
Article
This study aimed to determine if time-of-day could influence physical volleyball performance in females and to explore the relationship between chronotype and volleyball-specific performance. Fifteen young female athletes participated in a randomized counterbalanced trial, performing a neuromuscular test battery in the morning (9:00 h) and the evening (19:00 h) that consisted of volleyball standing spike, straight leg raise, dynamic balance, vertical jump, modified agility T-test and isometric handgrip tests. Chronotype was determined by the morningness-eveningness questionnaire. Compared to the morning, an increased performance was found in the standing spike (4.5%, p = .002, ES = 0.59), straight leg raise test (dominant-limb) (6.5%, p = .012, ES = 0.40), dynamic balance (non-dominant-limb) (5.0%, p = .010, ES = 0.57) and modified T-test (2.1%, p = .049, ES = 0.45) performance in the evening; while no statistical differences were reported in vertical jump tests or isometric handgrip strength. Moreover, no associations were found between chronotype and neuromuscular performance (r = −0.368–0.435, p = .052–0.439). Time-of-day affected spike ball velocity, flexibility in the dominant-limb, dynamic balance in the non-dominant-limb and agility tests. However, no association was reported among these improvements and the chronotype. Therefore, although the chronotype may not play critical role in volleyball-specific performance, evening training/matches schedules could benefit performance in semi-professional female volleyball players
... Participants were also requested to avoid strenuous activities 24 hours before each test session. All trials were performed at the same time of the day to avoid any effect of circadian variations on the results of the study [19]. Participants were enrolled in a crossover-study design, in which they acted as their own controls by taking part in two identical experimental sessions. ...
... Each player performed three maximal attempts interspersed with 45 s of passive recovery, and the best height jumped was recorded and used for statistical analysis as previously reported. The ICC for this test was 0.90 [19]. ...
... The ICC for this test was 0.90 [19]. ...
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To date, there is a lack of information about the optimal conditions of the warm-up to lead to a better performance in elite tennis players. The aim of this study was to compare the effects of two different warm-up protocols (dynamic vs. self-myofascial release with foam rolling) on neuromuscular variables associated with physical determinants of tennis performance. Using a crossover randomised experimental design, eleven professional men tennis players (20.6 ± 3.5 years) performed either a dynamic warm-up (DWU) or a selfmyofascial release with foam rolling (SMFR) protocol. DWU consisted of 8 min of dynamic exercises at increasing intensity and SMFR consisted of 8 min of rolling on each lower extremity unilaterally. Just before (baseline) and after completing warm-up protocols, players performed a countermovement jump (CMJ), the 5-0-5 agility test, a 10-m sprint test and the Straight Leg Raise and Thomas tests to assess range of motion. Compared to baseline, the DWU was more effective to reduce the time in the 5-0-5 test than SMFR (-2.23 vs. 0.44%, respectively, (p = 0.042, ηp2 = 0.19). However, both warm-up protocols similarly affected CMJ (2.32 vs. 0.61%, p = 0.373, ηp2 = 0.04) and 10-m sprint time changes (-1.26 vs. 1.03%, p = 0.124, ηp2 = 0.11). Changes in range of motion tests were also similar with both protocols (p = 0.448–1.000, ηp2 = 0.00–0.02). Overall, both DWU and SMFR were effective to prepare well-trained tennis players for highly demanding neuromuscular actions. However, DWU offered a better preparation for performing change of direction and sprint actions, and hence, in high-performance tennis players, the warm-up should include dynamic exercises.
... Previous studies confirmed that physiological, psychological, and performance parameters during physical exercise present diurnal variations (Chtourou et al., 2013bLópez-Samanes et al., 2017;Lopes-Silva et al., 2018;Pullinger et al., 2018). A recent review, revealed that performance in short-term high intensity exercise is time-of-day dependent with peak values were observed in the afternoon and amplitudes (i.e., difference between the maximal and minimal value) of ∼2-22% (Chtourou and Souissi, 2012). ...
... Reviewed data concerning the diurnal variation of muscle fatigue appear to be equivocal (Chtourou et al., 2013a). In this context, tennis performance (e.g., serving velocity and serving accuracy) is lower in the morning hours compared to the afternoon (López-Samanes et al., 2017). However, the majority of the studies reported that muscle fatigue with different physical tasks (e.g., Wingate test, repeated maximal voluntary contractions) is higher in the afternoon compared to the morning (Nicolas et al., 2007;Chtourou et al., 2012bChtourou et al., , 2013a. ...
... In well trained judo athletes (Chtourou et al., 2013a) and tennis players (López-Samanes et al., 2017) significant time-ofday differences have been reported, demonstrating diminished performances in the morning [i.e., handgrip (Chtourou et al., 2013a;López-Samanes et al., 2017), power during a Wingate test (Chtourou et al., 2013a) and CMJ, 10-m run, agility sprint, serving velocity and accuracy (López-Samanes et al., 2017)]. The divergence between the present study and other findings (Chtourou et al., 2013a;López-Samanes et al., 2017) could be attributed to the time-of-day of regular training of athletes. ...
Article
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Objectives: The aim of this study was to examine the effect of time of day on short-term repetitive maximal performance and psychological variables in elite judo athletes. Methods: Fourteen Tunisian elite male judokas (age: 21±1 years, height:172±7 cm, body-mass: 70.0±8.1 kg) performed a repeated shuttle sprint and jump ability (RSSJA) test (6×2×12.5 m every 25-s incorporating one countermovement jump (CMJ) between sprints) in the morning (7:00 a.m.) and afternoon (5:00 p.m.). Psychological variables (Profile of mood states (POMS-f) and Hooper questionnaires) were assessed before and ratings of perceived exertion (RPE) immediately after the RSSJA. Results: Sprint times (p>0.05) of the six repetition, fatigue index of sprints (p>0.05) as well as mean (p>0.05) jump height and fatigue index (p>0.05) of CMJ did not differ between morning and afternoon. No differences were observed between the two times-of-day for anxiety, anger, confusion, depression, fatigue, interpersonal relationship, sleep and muscle soreness (p>0.05). Jump height in CMJ 3 and 4 (p<0.05) and RPE (p<0.05) and vigor (p<0.01) scores were higher in the afternoon compared to the morning. Stress was higher in the morning compared to the afternoon (p<0.01). Conclusion: In contrast to previous research, repeated sprint running performance and mood states of the tested elite athletes showed no-strong dependency of time-of-day of testing. A possible explanation can be the habituation of the judo athletes to work out early in the morning.
... Two maximum isometric voluntary contractions were measured in the dominant hand using a calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan). Participant sat with 0 degrees of shoulder flexion, 0 degrees of elbow flexion and the forearm and hand in a neutral position such as previously reported in other studies [52]. The highest value out of two attempts was recorded (separated by a 45-s recovery period). ...
... The highest value out of two attempts was recorded (separated by a 45-s recovery period). Test-retest CV was 4.1% [52]. ...
... The maximum value out of the three shots was recorded. Test-retest CV was 3.5% [52]. ...
Article
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Previous investigations have found that several genes may be associated with the interindividual variability to the ergogenic response to caffeine. The aim of this study is to analyze the influence of the genetic variations in CYP1A2 (−163C > A, rs762551; characterized such as "fast" (AA genotype) and "slow" caffeine metabolizers (C-carriers)) and ADORA2A (1976T > C; rs5751876; characterized by "high" (TT genotype) or "low" sensitivity to caffeine (C-carriers)) on the ergogenic response to acute caffeine intake in professional handball players. Thirty-one professional handball players (sixteen men and fifteen women; daily caffeine intake = 60 ± 25 mg·d −1) ingested 3 mg·kg −1 ·body mass (bm) of caffeine or placebo 60 min before undergoing a battery of performance tests consisting of a countermovement jump (CMJ), a sprint test, an agility test, an isometric handgrip test, and several ball throws. Afterwards, the handball players performed a simulated handball match (2 × 20 min) while movements were recorded using inertial units. Saliva samples were analyzed to determine the genotype of each player for the −163C > A polymorphism in the CYP1A2 gene (rs762551) and for the 1976T > C polymorphism in the ADORA2A gene (rs5751876). In the CYP1A2, C-allele carriers (54.8%) were compared to AA homozygotes (45.2%). In the ADORA2A, C-allele carriers (80.6%) were compared to TT homozygotes (19.4%). There was only a genotype x treatment interaction for the ball throwing from 7 m (p = 0.037) indicating that the ergogenic effect of caffeine on this test was higher in CYP1A2 AA homozygotes than in C-allele carriers. In the remaining variables, there were no genotype x treatment interactions for CYP1A2 or for ADORA2A. As a whole group, caffeine increased CMJ height, performance in the sprint velocity test, and ball throwing velocity from 9 m (2.8-4.3%, p = 0.001-0.022, effect size = 0.17-0.31). Thus, pre-exercise caffeine supplementation at a dose of 3 mg·kg −1 ·bm can be considered as an ergogenic strategy to enhance some neuromuscular aspects of handball performance in professional handball players with low daily caffeine consumption. However, the ergogenic response to acute caffeine intake was not modulated by CYP1A2 or ADORA2A genotypes.
... Except for two studies 33,46 , better short-duration maximal exercise performances were found in the afternoon when single bouts of exercise were performed under neutral climate conditions. Short-duration maximal exercises that are influenced by the time of day include all-out swimming trials [47][48][49] , tennis services 37,40 , all-out cycl ing 13,23,24,27,28,35,36,38,42,43,[50][51][52][53][54] , maximal jumps 2,23,36,38,[40][41][42]46,49,[55][56][57] , repeated sprint ability 2,33,44,46,56,[58][59][60][61][62] , one repetition maximum (1RM) assessments [63][64][65][66] as well as other force-velocity based tests 35,40,49,54,62,63,67 . ...
... Except for two studies 33,46 , better short-duration maximal exercise performances were found in the afternoon when single bouts of exercise were performed under neutral climate conditions. Short-duration maximal exercises that are influenced by the time of day include all-out swimming trials [47][48][49] , tennis services 37,40 , all-out cycl ing 13,23,24,27,28,35,36,38,42,43,[50][51][52][53][54] , maximal jumps 2,23,36,38,[40][41][42]46,49,[55][56][57] , repeated sprint ability 2,33,44,46,56,[58][59][60][61][62] , one repetition maximum (1RM) assessments [63][64][65][66] as well as other force-velocity based tests 35,40,49,54,62,63,67 . ...
... Except for two studies 33,46 , better short-duration maximal exercise performances were found in the afternoon when single bouts of exercise were performed under neutral climate conditions. Short-duration maximal exercises that are influenced by the time of day include all-out swimming trials [47][48][49] , tennis services 37,40 , all-out cycl ing 13,23,24,27,28,35,36,38,42,43,[50][51][52][53][54] , maximal jumps 2,23,36,38,[40][41][42]46,49,[55][56][57] , repeated sprint ability 2,33,44,46,56,[58][59][60][61][62] , one repetition maximum (1RM) assessments [63][64][65][66] as well as other force-velocity based tests 35,40,49,54,62,63,67 . ...
Article
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Time-of-day dependent fluctuations in exercise performance have been documented across different sports and seem to affect both endurance and resistance modes of exercise. Most of the studies published to date have shown that the performance in short-duration maximal exercises (i.e. less than 1 min - e.g. sprints, jumps, isometric contractions) exhibits diurnal fluctuations, peaking between 16:00 and 20:00 h. However, the time-of-day effects on short duration exercise performance may be minimized by the following factors: (1) short exposures to moderately warm and humid environments; (2) active warm-up protocols; (3) intermittent fasting conditions; (4) warming-up while listening to music; or (5) prolonged periods of training at a specific time of day. This suggests that short-duration maximal exercise performance throughout the day is controlled not only by body temperature, hormone levels, motivation and mood state but also by a versatile circadian system within skeletal muscle. The time of day at which short-duration maximal exercise is conducted represents an important variable for training prescription. However, the literature available to date lacks a specific review on this subject. Therefore, the present review aims to (1) elucidate time-of-day specific effects on short-duration maximal exercise performance and (2) discuss strategies to promote better performance in short-duration maximal exercises at different times of the day.
... Most studies have estimated higher performance in the afternoon, specifically around 16:30-19:00 (Table 2) (Aloui et al. 2017;Chtourou et al. 2018Di Cagno et al. 2013;Kunorozva et al. 2014;Lericollais et al. 2011;Lok et al. 2020;López-Samanes et al. 2016;Petit et al. 2013;Silveira et al. 2020;West et al. 2014;Zarrouk et al. 2012). However, some authors (Ammar et al. 2015b), working with weightlifters, bring forward to 02:00 h the improvement in performance and a lower perception of effort exerted (RPE). ...
... 5 of the 6 articles found on aerobic performance showing better data for PM tests ( RSA test (2 x 10" + braking resistance generated by a 5% slope). RSA: higher performance at PM (12:30,14:30,16:30,18:30) Lok et al. 2020;López-Samanes et al. 2016;Silveira et al. 2020). For the anaerobic tests, the findings show less consensus as no significant differences between AM and PM were always found Kunorozva et al. 2014). ...
... Nevertheless, the best results (distance covered, speed, jumping power, time spent . . .) were obtained in the PM, toward the early afternoon (Table 2) (Aloui et al. 2017;López-Samanes et al. 2016;Petit et al. 2013;West et al. 2014). This could be due to the fact that in this type of test the most important thing is the power and strength of the first instant. ...
Article
Chronobiology is the scientific discipline of study of biological rhythms, a term that has gained ground in the sports world. Recently numerous studies have indicated that the time of day in which sports are practiced influences the achievement of good physical performance. The aim of this review was to study the relationship between circadian rhythms and physical performance, according to the latest published data. In addition, the physiological processes involved in the physical response and the differences according to the type of sport and athletes’ characteristics were studied. A bibliographic search was carried out through five databases (Pubmed, Scopus, Researcher Gate, Google Scholar, UOC Library), focusing on articles published in the last ten years and written in English and Spanish. 36 papers met the inclusion criteria. Body temperature is a factor that shows a circadian pattern with a marked peak in the later afternoon, time of the day at which physical performance is at its highest, i.e. speed, agility, distance covered, jumping power. The perception of effort is also higher in the afternoon. Regarding the chronotype, evening types seem to be the most affected to do sports out of their optimal time-of-day. The tendency shows more morning types as age increases. Training sessions should be planned according to the optimal time of day for each athlete. It’s essential to take into account individual chronotype. The desynchronization of circadian rhythms can cause a decrease in physical performance.
... In this sense, the acrophase of body temperature has been identified to be concurrent with peaks in physical capacities such as muscular strength [5] and anaerobic power [4,7], which peak in the evening. The later acrophase of physical capacities in the evening is therefore considered the primary factor underpinning the consistent finding that sports performance typically peaks in the evening [1,2,[8][9][10][11]. ...
... This consensus extends to sport-specific skills such as soccer volleying, chipping, and dribbling execution [1,12]; badminton serve accuracy [11]; and tennis serve velocity [9,10], demonstrating diurnal variations favoring afternoon (14:00-16:00 h) and evening (19:00-21:00 h) performance compared to morning (07:00-09:00 h). ...
... While diurnal variations may exist among sport-specific skills, previous studies have failed to report differences across the day, specifically according to player chronotypes [1,[9][10][11]. Further, there remains limited data examining the effect of chronotype on in-game sport-specific skill performance according to the time of day. The potential effect of chronotype according to time of day is of particular importance, as athletes tend to choose, pursue, and excel in sports aligning to their chronotype with a predominance of neither-types (N-types) exhibited among team sport athletes who are often subjected to games scheduled in the evening for their respective sport [13,14], that is, athletes who display neither a preference for morningness nor eveningness [15,16]. ...
Article
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Sport-specific skills display diurnal variation across various team sports such as badminton and tennis serving accuracy and soccer dribbling, volleying, and chipping execution. However, the effects of athlete chronotype on in-game sport-specific skill performance according to time of day across team sports is not well understood. Therefore, the aim of this study was to identify the effect of player chronotype on in-game basketball performance during evening games. Professional male basketball players (n = 11) completed a morningness–eveningness questionnaire and were categorized according to chronotype (morning-type: n = 4; neither-type: n = 6; evening-type: n = 1). Box score data from the 2019/20 season were utilized to determine individual in-game performance during evening games played after 18:00 h. Composite metrics (i.e., effective field goal percentage, offensive rating, defensive rating, and player efficiency) were used as indicators of player performance. Non-significant (p ≥ 0.21) differences were evident between M-types and N-types for most performance measures. Small to very large effects were observed in the number of rebounds favoring M-types, and three-point shots attempted and made, assists, and steals favored N-types. In-game performance appeared to not be affected by chronotype (i.e., M-type vs. N-type) in evening games among professional male basketball players. The lack of observed effect between chronotype and in-game performance suggest coaching staff may not need to consider player chronotype when developing a match strategy or assigning player roles if largely dealing with M-types and N-types. However, to ensure the greatest specificity, coaching staff may endeavor to schedule habitual training times in line with that of competition in an effort to align player circadian rhythms to games.
... High performance in tennis is associated with higher values of strength and power output [5], agility [6], and serve velocity [7]. Other secondary determinant aspects have been proposed, such as environmental [8], nutrition [9], chronobiological aspects [10], and recovery strategies [11]. ...
... Three hours after intake of BJ or PLA, subjects performed a standardized dynamic warm up protocol [33], and then a neuromuscular test battery was carried out, consisting of a tennis serve velocity test (SVT), countermovement jump (CMJ), isometric handgrip strength (IHS), 5-0-5 agility test (5-0-5), and 10 m sprint (10-m) ( Figure 1). Furthermore, in both trials, the experimental procedures were performed at the same hour of the day to avoid the influence of circadian rhythms on performance [10]. ...
... Two maximum isometric voluntary contractions were measured in the dominant hand using a calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan). Volunteers sat with 0 degrees of shoulder flexion, 0 degrees of elbow flexion, and the forearm and hand in a neutral position [10]. The highest value out of two attempts was recorded as the maximum voluntary handgrip strength. ...
Article
Full-text available
Beetroot juice (BJ) contains high levels of inorganic nitrate (NO3−) and its intake has good evidence in increasing blood nitrate/nitrite concentrations. The ingestion of BJ has been associated with improvements in physical performance of endurance sports, however the literature in intermittent sports is scarce. The aim of this study was to investigate whether BJ could improve physical performance in tennis players. Thirteen well-trained tennis players (25.4 ± 5.1 years) participated in the study during their preparatory period for the tennis season. Subjects were randomly divided into two groups and performed a neuromuscular test battery after either BJ or placebo (PLA) consumption. Both trials were executed on two separate days, in randomized order, with one week of wash out period. The test battery consisted of serve velocity test (SVT), countermovement jump (CMJ), isometric handgrip strength (IHS), 5-0-5 agility test (5-0-5), and 10 m sprint (10-m). No significant differences were found in SVT (1.19%; p = 0.536), CMJ (0.96%; p = 0.327), IHS (4.06%; p = 0.069), 5-0-5 dominant and nondominant side (1.11–2.02%; p = 0.071–0.191) and 10-m (1.05%; p = 0.277) when comparing BJ and PLA ingestion. Thus, our data suggest that low doses of BJ (70 mL) consumption do not enhance tennis physical performance.
... Regarding barbell velocity monitoring, several recent studies conducted on experienced athletes, reported that minor increments in strength (2-5% 1RM) resulted in very important performance enhancement (effect size = 0.20-0.85) at different maximal and submaximal loading intensities [1,[15][16][17]. The meaningfulness of improvements is associated with the resistance training program [1], the dehydration status [18], the acute ingestion of ergogenic aids [17] or the circadian rhythm effect [15]. ...
... at different maximal and submaximal loading intensities [1,[15][16][17]. The meaningfulness of improvements is associated with the resistance training program [1], the dehydration status [18], the acute ingestion of ergogenic aids [17] or the circadian rhythm effect [15]. The most recent studies around the VBRT approach stated that 0.07 mÁs À1 increments resulted in 5.0% 1RM enhancements in the most common resistance training exercises as bench press and squat [2,5,19]. ...
Article
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This study aims to identify the measurement error associated with the mean movement velocity when using high-speed camera-based methods and video analysis during resistance training. Eleven resistance-trained men (26.0 ± 3.4 years) completed a progressive loading test in bench press exercise. Measurements from concentric mean velocity (MV), distance and time were obtained from a linear velocity transducer (T-Force) and videos recorded with high speed cameras on readily available smartphones (Samsung S6, Xiaomi A1, and iPhone X) and digital photo cameras (Casio FH20). Videos were examined using video analysis software (Kinovea). Despite the high correlations detected, the Bland-Altman analyses revealed that all high speed cameras produced substantial overestimation of barbell MV against high loads >60% 1RM (MV error = 0.06 ± 0.03 m·s-1 to 0.08 ± 0.04 m·s-1), but mainly against low loads <60% 1RM (MV error = 0.13 ± 0.06 m·s-1 to 0.20 ± 0.09 m·s-1). The maximum estimation error of the load being lifted (%1RM) was considerable both for low (8.5% to 12.7% 1RM) and high loads (13.9% to 22.6% 1RM). Among other practical limitations, the video-based system using different high-speed cameras and smartphone devices presents severe limitations when estimating mean concentric velocity, especially when recording low loads at high velocity.
... The high dietary fiber makes pulses a healthy food choice, because when pulses are consumed on a chronic basis (i.e., 8-16 weeks), they reduce harmful blood lipids [8,9], a major risk factor for cardiovascular disease. A number of studies evaluating diet in well-trained soccer players (males and females ranging in age from [16][17][18][19][20][21][22] years across studies) indicate that soccer players have relatively low intake of dietary fiber (i.e., about 55-67% of the recommended/reference intake) [10,11] and this may put them at risk of development of cardiovascular disease later in life [12]. It has been proposed that soccer players (mean age of 20 years) may avoid foods high in dietary fiber for fear it might cause gastrointestinal discomfort during training or games [13]. ...
... Athletic performance was assessed during match play during the fourth week of each diet phase. Assessment of matches was during the afternoon (Saturdays), which assured that the effects of circadian rhythms on intermittent sport performance between matches was minimal [18]. Variables assessed included total distance covered during the match, maximal velocity, and percent of time resting/walking/jogging (<14.4 km/h), running (14.4-19.7 km/h), and sprinting (≥19.8 km/h) [17]. ...
Article
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Pulses (i.e., lentils, chickpeas, beans, peas) are low-glycemic index, high-fiber foods that are beneficial for improving blood lipids. Young soccer players typically have low dietary fiber intake, perhaps because of concerns regarding gastro-intestinal problems during exercise performance. Twenty-seven (17 females) soccer players were randomized to receive a pulse-based diet or their regular diet for four weeks in a cross-over study and evaluated for changes in blood lipids and athletic performance, with 19 (22 ± 6y; 12 females) completing the study (eight participants withdrew because of lack of time). Women increased high density lipoproteins (+0.5 ± 0.7 vs. −0.6 ± 0.3 mmol/L; p < 0.01) and reduced total cholesterol to high density lipoprotein ratio (−2.4 ± 2.9 vs. +2.6 ± 2.2; p < 0.01) on the pulse-based vs. regular diet, respectively, while there were no differences between diet phases in men. Athletic performance assessed by distance covered during games by a global positioning system was not significantly different during the pulse-based vs. regular diet (9180 ± 1618 vs. 8987 ± 1808 m per game; p = 0.35). It is concluded that a pulse-based diet can improve blood lipid profile without affecting athletic performance in soccer players.
... Maximal IHS was measured in the dominant hand using a calibrated handgrip dynamometer (Takei 5101; Takei, Tokyo, Japan) as previously reported. 26 The highest value out of 2 attempts was recorded and used for statistical analysis. Afterward, participants completed 2 repetitions of a maximal CMJ test with hands on the hips while jump height was measured using an infrared-beams jump system (Optojump Next, Microgate, Bolzano, Italy). ...
... −0.13 to 0.26), the distance covered at sprint velocity (8.57 [3.17] vs 7.97 [2.86] m/min; P = .164; ...
Article
Purpose: To investigate the effects of acute caffeine (CAFF) intake on physical performance in elite women handball players. Methods: A total of 15 elite women handball players participated in a randomized, double-blind study. In 2 different trials, participants ingested either a placebo (cellulose) or 3 mg of CAFF per kilogram of body mass (mg/kg bm) before undergoing a battery of neuromuscular tests consisting of handball throws, an isometric handgrip strength test, a countermovement jump, a 30-m sprint test (SV) and a modified version of the agility T test. Then, participants performed a simulated handball game (2 × 20 min), and movement patterns were recorded with a local positioning system. Results: Compared with the placebo, CAFF increased ball velocity in all ball throws (P = .021-.044; effect size [ES] = 0.39-0.49), strength in isometric handgrip strength test (350.8 [41.2] vs 361.6 [46.1] N, P = .034; ES = 0.35), and countermovement-jump height (28.5 [5.5] vs 29.8 [5.5] cm; P = .006; ES = 0.22). In addition, CAFF decreased running time in the SV (4.9 [0.2] vs 4.8 [0.3] s; P = .042; ES = -0.34). In the simulated game, CAFF increased the frequency of accelerations (18.1 [1.2] vs 18.8 [1.0] number/min; P = .044; ES = 0.54), decelerations (18.0 [1.2] vs 18.7 [1.0] number/min; P = .032; ES = 0.56), and body impacts (20 [8] vs 22 [10] impacts/min; P = .032; ES = 0.30). However, postexercise surveys about self-reported feelings of performance indicate that players did not feel increased performance with CAFF. Conclusion: Preexercise ingestion of 3 mg/kg bm of CAFF improved ball-throwing velocity, jump, and sprint performance and the frequency of in-game accelerations and decelerations in elite women handball players.
... El IHS máximo se midió en la mano dominante usando un dinamómetro calibrado (Takei 5101; Takei, Tokio, Japón). Como se puede observar en la Figura 11, las jugadoras se encontraban de pie con 0 grados de flexión del hombro, 0 grados de flexión del codo y el antebrazo y la mano en posición neutral (López-Samanes et al., 2017a). El valor más alto de contracción muscular de dos intentos se registró y se utilizó para el análisis estadístico. ...
... El IHS máximo se midió en la mano dominante usando un dinamómetro calibrado (Takei 5101; Takei, Tokio, Japón). Todos los jugadores se encontraban de pie con 0 grados de flexión del hombro, 0 grados de flexión del codo y el antebrazo y la mano en posición neutral (López-Samanes et al., 2017a). El promedio de los valores de contracción muscular de dos intentos se registró y se utilizó para el análisis estadístico. ...
Thesis
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Suplementación Deportiva en Balonmano: Efecto de la Cafeína e Influencia del CYP1A2 y ADORA2A en el Rendimiento Deportivo en Jugadores de Élite de Balonmano
... Referees and assistant referees were tested twice: (a) 60 min prior to the onset of the match and (b) immediately after the end of the match. Before the first measurement, all participants underwent a standardized warm-up consisting of 5 min of running at low intensity (10 km·h −1 ) and dynamic warm-up exercises, as previously suggested [28]. A week before testing, referees and assistant referees were familiarized with all testing procedures to reduce the influence of the learning effect on the results of the investigation. ...
... Additionally, participants' internal load imposed by the match was calculated by the session rating of perceived exertion [29]. During the whole duration of each match, air temperature and humidity were measured with a portable weather station (WMR 108, Mextech, India; [28]). All matches were completed on an artificial grass pitch (AT; fibre: monofilament of polyethylene of 60 mm in height) within a dimension of~100 × 70 m. ...
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The aim of this study was to examine the acute effect of officiating a football (soccer) match on isometric knee flexion strength and passive hip flexion range-of-motion (ROM) in referees and assistant football referees. Twelve referees (25.3 ± 3.3 years) and twenty-three assistant referees (25.1 ± 4.8 years) underwent measurements on isometric knee flexion strength and passive hip flexion ROM before and after officiating an official football match. Referees' and assistant referees' running patterns were monitored during the match using GPS technology. In comparison to pre-match values, referees reduced their isometric knee flexion strength (−12.36%, p = 0.046, Effect size [ES] = −0.36) in the non-dominant limb, while no significant differences were reported in the dominant limb (−0.75%, p = 0.833, ES = −0.02). No effect of the match was found in hip flexion ROM values in dominant (−4.78%, p = 0.102, ES = −0.15) and non-dominant limb (5.54%, p = 0.544, ES = 0.19). In assistant referees, the pre-to-post-match changes in isometric knee flexion strength (dominant limb −3.10%, p = 0.323, ES = −0.13; non-dominant limb −2.18%, p = 0.980, ES= 0.00) and hip flexion ROM (dominant limb 1.90% p = −0.816, ES = 0.13; non-dominant limb 3.22% p = 0.051, ES = 0.23) did not reach statistical significance. Officiating a match provoked a reduction in isometric knee flexion strength in the non-dominant limb of football referees, while no differences were reported in assistant referees.
... Testing sessions included a neuromuscular test battery consisted in countermovement jump (CMJ), isometric handgrip strength, a modified version of the agility T-test, and 10-m and 20-m sprint tests, followed by a 40-minute monitored basketball match ( Figure 1). Experimental procedures were performed at the same hour in the evening (19:00 h) to avoid the influence of circadian rhythms on performance such as previously reported in other intermittent sports [36]. Environmental conditions were measured using a portable weather station (WMR 108, Mextech, India) and the Windy app for Android, with all the measurement made under similar conditions (16 °C, 45% humidity, wind < 5 km•h -1 ). ...
... The best performance for each test was considered for the analysis. Measurements were obtained using devices with very high reliability [43][44][45] and according to standard procedures with high intraclasscorrelation (ICC > 0.903) and low coefficient of variation (CV < 1.5 %) [36,46]. All these tests has been successfully used for physical performance assessment in young basketball players [47][48][49]. ...
Article
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Whereas beetroot juice (BJ) supplementation is shown to increase physical performance in endurance activities, its benefits in team sports has been barely studied. In this randomized placebo-controlled study, we investigated the effects of BJ acute supplementation in improving neuromuscular performance and physical match activity in basketball. Ten young male competitive basketball players aged 15-16 years received 140 mL of BJ or placebo (PLA) on two separated days in a balanced cross-over design. Testing sessions comprised a neuromuscular test battery consisting of a countermovement jump (CMJ), isometric handgrip strength, 10-m/20-m sprint and agility T-test, followed by a 40-minute simulated basketball match. Physical match activity (distances, speeds, accelerations, and decelerations) was monitored using an inertial tracking system (Wimu Pro TM) Results revealed no significant effects of BJ on CMJ (p = 0.304, ES = 0.13), isometric handgrip strength (p = 0.777, ES = 0.06), 10-m (p = 0.820, ES = 0.10), and 20-m sprint (p = 0.540, ES = 0.13), agility T-test (p = 0.979, ES ≤ 0.01) and any physical match demands (p > 0.151, ES = 0.13-0.48). Acute moderate doses of BJ (12.8 mmol of NO3 −) was not effective in improving neuromuscular performance (jump height, isometric handgrip strength, sprint, and agility) or physical match requirements in young trained basketball players the day of the competition.
... "Chronobehavior": Chronotype and Training/Competition Time Chronotype is a genetically determined predisposition that modifies each individual's preference to be most active in the morning (morning-type), middle of the day (neither-type), or in the evening (evening-type) [53,54]. In elite sport, extreme chronotypes (i.e., definite morning type or definite evening type) are unusual and chronotype distribution mainly depends on the chosen sport and respective training time of the athletes [55][56][57]. Vitale et al. [58] showed that sleep quality-moving time, immobility time, sleep efficiency, actual sleep time-was poorer in the morning-type than in the evening-type players after the evening high-intensity training session (20:00), whereas no significant changes to the sleep quality of the two chronotypes was observed after the morning session (08:00). However, a limitation of this study is the fact that morning-types generally have consistently early bedtimes and waking times. ...
... Moreover, seasonal phases generally correspond to specific environmental conditions. In this respect, future experimental studies on sleep and elite sport should systematically report seasonal phase and, ideally, be conducted during the early fall or winter to minimize the effects of environmental conditions, i.e., outdoor light levels [84] and morning/afternoon temperature differences [57]. ...
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Practicing sport at the highest level is typically accompanied by several stressors and restrictions on personal life. Elite athletes' lifestyle delivers a significant challenge to sleep, due to both the physiological and psychological demands, and the training and competition schedules. Inter-individual variability of sleep patterns (e.g., sleep requirements, chronotype) may have important implications not only for recovery and training schedules but also for the choice of measures to possibly improve sleep. This article provides a review of the current available literature regarding the variability of sleep among elite athletes and factors possibly responsible for this phenomenon. We also provide methodological approaches to better address the inter-individual variability of sleep in future studies with elite athletes. There is currently little scientific evidence supporting a specific influence of one particular type of sport on sleep; sleep disorders may be, however, more common in strength/power and contact sports. Sleep behavior may notably vary depending on the athlete's typical daily schedule. The specificity of training and competition schedules possibly accounts for the single most influential factor leading to inconsistency in sleep among elite athletes (e.g., "social jet lag"). Additionally, athletes are affected by extensive exposure to electric light and evening use of electronic media devices. Therefore, the influence of ordinary sleep, poor sleep, and extended sleep as important additional contributors to training load should be studied. Future experimental studies on sleep and elite sport performance should systematically report the seasonal phase. Boarding conditions may provide a good option to standardize as many variables as possible without the inconvenience of laboratory. The use of interdisciplinary mixed-method approaches should be encouraged in future studies on sleep and elite sport. Finally, high inter- and intra-individual variability in the athletes' sleep characteristics suggests a need for providing individual responses in addition to group means.
... effect magnitudes would fluctuate in favour of chronotypes suited to the time-of-day being tested). Furthermore, our findings contrast previous data in other sports indicating diurnal variations exist in skill performance predominantly examining N-type athletes with tennis first serve accuracy ([16:30-18:00h]; 15,16 ), badminton serving accuracy ([14:00h]; 17 ), and soccer chipping, volleying ([16:00h, 19:00-21:00h]; 9,10 ), and dribbling execution 9 being significantly (p <0.05) better in the afternoon and evening compared to the morning (07:00-09:00h). The contrast between the current findings and those provided in previous research may be attributed to the participants recruited in each study. ...
... The contrast between the current findings and those provided in previous research may be attributed to the participants recruited in each study. In this regard, the current study examined professional basketball players compared to previous studies that examined amateur 9,10,15-17 and semi-professional athletes 16 . Indeed, professional athletes likely possess a higher degree skill mastery specific to their chosen sports compared to lower-level athletes, which may make them more resistant to diurnal variations in skill execution. ...
Article
Athlete chronotype has been documented to underpin diurnal variations in skill execution across various team sports. However, no research has explored the effects of athlete chronotype on basketball-specific skills at different times of the day. Therefore, the aim of this study was to explore diurnal variations in basketball shooting accuracy according to chronotype. Professional, male basketball players (n = 13) completed a Morningness- Eveningness Questionnaire and were categorised into chronotypes using a tertile split technique (morning-types: n = 4; neither-types: n = 4; evening-types: n = 5). Players completed separate trials of a shooting accuracy test in the morning (08:00-09:30h) and afternoon (15:00-16:30h) with each trial consisting of 20 shots attempted from four court locations at either two- or three-point distances and one-shot location from the free-throw line (100 shots in total). Each shot attempt was scored using a 0-3-point scale with higher scores awarded to more accurate shots. Non-significant (p >0.05) differences in shooting scores were evident between morning and afternoon trials for each chronotype group, with small-large effects in shooting scores favouring the morning across groups. Moreover, non-significant (p >0.05) differences in shooting scores were apparent between chronotype groups in the morning (small-large effects) and afternoon (moderate-large effects). Shooting accuracy appears to remain consistent across morning and afternoon performances irrespective of player chronotype in a professional basketball team, suggesting coaches may not need to schedule training sessions involving shooting tasks at specific times of the day to optimise shooting accuracy in players.
... Tennis is an intermittent sport characterized by high-intensity efforts interspersed with periods of low-intensity activity (e.g., active recovery between points and rest between changeover breaks) over a variable period (i.e., 1-5 h) ( López-Samanes et al., 2017). During a tennis match, the players cover around 1,500-3,100 m ( Gallo-Salazar et al., 2015;Pereira et al., 2016) and report ratings of perceived exertion (RPE) of ~5.5 units after matches ( Murphy et al., 2016). ...
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Background Groin injuries are some of the most common injuries tennis players suffer. Several factors (e.g., post-match decrease in hip adductor (ADD) strength) have been proposed as possible mechanisms for increasing the incidence of this type of injury. However, the risk factors of developing groin injuries after a tennis match have not yet been delineated. Objective The aim of this study was to determine the effect of tennis match-play on isometric ADD and abductor (ABD) strength and passive hip range of motion (ROM). Methods Twenty-six male tennis players (20.30 ± 4.98 years) took part in this study. Participants completed an evaluation of strength and flexibility hip measurements before and after a simulated tennis match. Dominant and non-dominant passive hip ROM, ADD and ABD isometric strength, and the ADD/ABD strength ratio were measured before and immediately post-match. A global positioning system (GPS) and a session rating of perceived exertion (RPE) were used to assess the locomotive demands and internal match load. Results Isometric dominant ADD strength (17.8%, p ≤ 0.01) and ADD/ABD strength ratio (11.6%, p = 0.04) were lower post-match compared to the pre-match values. No between-limbs differences were observed for isometric ADD strength, ABD strength, and passive hip ROM tests. RPE showed an expected increase between pre- vs. post-match (pre- vs. post-warming-up, 3.42 ± 2.08 vs. 5.62 ± 2.29, p < 0.01). In addition, a significant relationship between ADD strength and the volume of tennis practice per week was found, stablishing that tennis players with lower volume of training per week suffered a reduction in ADD strength in their dominant limb after match-play ( r = 0.420, p = 0.04). Conclusion The assessment of ADD strength and the ADD/ABD strength ratio in the dominant limb may be considered a post-match tool that can be used to identify players who require rest and additional recovery strategies before competing again.
... Limited studies have investigated the effect of CR on vertical jump performances [12][13][14]. One such study was performed by Lopez-Samanes et al. [15], who investigated the effect of CR on tennis performance. In that study, significant increases were obtained in countermovement jumps (CMJs) in the afternoon compared to morning. ...
Article
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Abstract BACKGROUND: The circadian rhythm (CR) is a 24-hour cyclic period that influences a wide array of physiological systems and performance sports. However, its specific effect on drop jump (DJ) scores have not been studied. OBJECTIVE: To investigate the effect of circadian rhythm on DJ performances. METHODS: Thirty-three healthy university students (men, n = 16, age: 23.47±2.9 years; fewomen, n = 17, age: 22.25 ±2.27 years) participated in this study. Subjects were tested twice, over two separate days, once in the morning and once in the evening. Subjects started from a drop height of 20 cm and continued until the height where the reactive strength index (RSI) started to decrease. This height was recorded as the optimal drop height (ODH). Ground contact time (GCT) and jump height were also recorded. RESULTS: The ODH values were similar between testing sessions for both genders (p > 0.05). A significant increase in jump height during the evening session was observed in men (p = 0.005, d = 0.80). The RSI values increased significantly in men (p = 0.006, _2 = 0.77) while GCT was similar in both genders (p > 0.05). CONCLUSION: In men, the optimal time of day for DJ explosive training is the evening. Women may benefit from this type of training both during morning and evening sessions. Keywords: Circadian rhythm, drop jump, reactive strength index, optimal drop height, jump height, ground contact time
... Velocity and power of movement appear to be particularly vulnerable to diurnal fluctuations (Bernard et al., 1997;Mora-Rodríguez et al., 2012. Ballistic movement performance has been shown to be lower during morning times (López Samanes et al., 2017). Bernard et al. reported that jumping power and maximal anaerobic velocity were higher in the afternoon than in the morning (Bernard et al., 1997). ...
Article
Purpose: The purpose of this study was to investigate how time-of-day training preference influences resistance-exercise performance. Methods: Resistance trained males (n = 12) were recruited for this study. In a crossover, counterbalanced design, participants completed two separate bench-press exercise trials at different times of day: (a) morning (AM; 8:00 hr) and (b) evening (PM; 16:00 hr). Participants answered a questionnaire on time-of-day training preference and completed a preferred (PREF) and nonpreferred (NON-PREF) time-of-day trial. For each trial, motivation was measured using a visual analog scale prior to exercise. Participants completed 2 sets × 2 repetitions at 75% 1-RM with maximum explosiveness separated by 5 min of rest. Mean barbell velocity was measured using a linear position transducer. Participants then completed 1 set × repetitions to failure (RTF) at 75% 1-RM. Rate of perceived exertion (RPE) was measured immediately following exercise. Results: Regardless of preference, velocity (p = .025; effect size (ES) = 0.43) was higher during the PM versus AM trial. However, there were no significant differences in velocity (p = .368; ES = 0.37) between PREF and NON-PREF time of day. There were no significant differences for repetitions between PREF and NON-PREF times (p = .902; ES = 0.03). Motivation was higher in the PREF time versus NON-PREF (p = .015; ES = 0.68). Furthermore, RPE was significantly lower during the PREF time of day (p = .048; 0.55). Conclusions: Despite higher barbell velocity collectively at PM times, time-of-training preference did not largely influence resistance-exercise performance, while motivation is higher and RPE is lower during preferred times.
... than in the evening (18.00pm). Another study conducted by Lopez -Samanes et al., (2016) on elite tennis players, they found a 4.5 ± 5.1% higher vertical jump height in the evening (16.30) hours than in the morning (09.00). Heishman et al., (2017) ascertained that basketball players had a lower vertical jump performance in the morning hours (07.00-09.00am) ...
... Isometric handgrip strength (IHS) was measured twice for the dominant hand using a calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan) with 30 seconds of passive recovery between trials. Participants sat with 0 of shoulder flexion and elbow flexion, and the forearm and hand in a neutral position and exerted their maximal strength during 5 seconds [31]. The highest value of the dominant hand was recorded and used for statistical analysis as the maximum voluntary handgrip strength. ...
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Background: this study examined the effects of caffeine supplementation on anaerobic performance, neuromuscular efficiency and upper and lower extremities fatigue in Olympic-level boxers. Methods: Eight male athletes, members of the Spanish National Olympic Team, were enrolled in the study. In a randomized double-blind, placebo-controlled, counterbalanced, crossover design, the athletes completed 2 test sessions after the intake of caffeine (6 mg·kg-1) or placebo. Sessions involved initial measures of lactate, handgrip and countermovement jump (CMJ) performance, followed by a 30-seconds Wingate test, and then final measures of the previous variables. During the sessions, electromiography (EMG) data were recorded on the gluteus maximus, biceps femoris, vastus lateralis, gastrocnemius lateral head and tibialis anterior. Results: caffeine enhanced peak power (6.27%, p < 0.01; Effect Size (ES) = 1.26), mean power (5.21%; p < 0.01; ES = 1.29) and reduced the time needed to reach peak power (-9.91%, p < 0.01; ES = 0.58) in the Wingate test, improved jump height in the CMJ (+2.4 cm, p < 0.01), and improved neuromuscular efficiency at peak power in the vastus lateralis (ES = 1.01) and gluteus maximus (ES = 0.89), and mean power in the vastus lateralis (ES = 0.95) and tibialis anterior (ES = 0.83). Conclusions: in these Olympic-level boxers, caffeine supplementation improved anaerobic performance without affecting EMG activity and fatigue levels in the lower limbs. Further benefits observed were enhanced neuromuscular efficiency in some muscles and improved reaction speed.
... Although players were able to run longer at low (eg, from 0 to 3 m·s −1 ) and high (eg, from 3 to 4 m·s −1 ) velocities during the AFT match, running activities per minute of play were similar in both matches. Based on previous research revealing that high-level tennis players performed better in the AFT compared with the MOR, 27 this may have an important impact on the outcome of a match. In this regard, and based on the fact that players covered the same running distance per minute of play for an extra 30 minutes in AFT match, it might be deduced that they were able to perform better during the AFT match. ...
Article
PURPOSE:: This study aimed to determine whether the game activity and physiological responses of young tennis players differed depending on the session of play (e.g., morning (MOR) vs. afternoon (AFT)) and the final match outcome (e.g., winners vs. losers), during a simulated competition with two matches on the same day. METHODS:: Twelve well-trained male tennis players (14.5±0.8 years) took part in a simulated competition of two 3-set matches separated by 3 h. All the matches were video-recorded and the participants were monitored using 10 Hz global positioning (GPS) units including a heart-rate (HR) monitor. Effect size (ES) statistics were used to investigate the magnitudes of the differences. RESULTS:: During the AFT matches, in absolute terms, players covered longer total distance (ES=moderate), ran more distance between 0 and ≤ 4m·s-1 (ES=small-to-large) compared to MOR matches. Total duration was also longer (ES=large) in the AFT, where the rest time between rallies was also longer (ES=very large). HR was similar during both AFT and MOR matches, but higher rates of perceived exertion (RPE) (ES=moderate) were reported in the AFT. Only peak running velocity was observed to be likely higher for losers compared to winners (ES=small). CONCLUSIONS:: Game activity and physiological responses of young tennis players differ when two consecutive matches are played on the same day. These data might help to elucidate the need for specific pre-competition training loads and/or in-between match/session recovery strategies when facing overloaded competitions.
... Calibration was performed according to the manufacturer's specifications prior to each test. The serve test procedure was conducted as previously reported elsewhere [22]. Briefly, the radar was positioned in the tennis court on the center of the baseline, 4 m behind the server, aligned with the approximate height of ball contact (~2.2 m) and pointing down the center of the court. ...
Article
Shoulder pain has been associated with glenohumeral internal rotation deficit (GIRD) and a reduction in external rotation (ER) strength; however, in tennis players, there is scarce evidence regarding the impact of a single match on shoulder range of motion (ROM), strength and serve speed. The aim of this study was to determine the acute effect of a single tennis match on shoulder rotation ROM, isometric strength and serve speed. Twenty-six professional tennis players participated in the study (20.4±4.4 years; 10.5±3.2 years tennis expertise ; 20.5±5.4 h/week training). Passive shoulder external (ER-ROM) and internal rotation ROM (IR-ROM), ER and IR isometric strength were measured before and after a single tennis match (80.3±21.3 min) in both shoulder´s. Moreover, the total arc of motion (TAM) and ER/IR strength ratio were calculated. Video analysis was used to assess the number of serves and groundstrokes, while a radar gun was utilized to measure maximal ball speed. In the dominant shoulder, compared to pre-match levels, IR-ROM was significantly reduced (-1.3%; p = 0.042), while ER-ROM (5.3%; p = 0.037) and TAM (3.1%; p = 0.050) were significantly increased. In the non-dominant shoulder, ER-ROM (3.7%; p = 0.006) was increased. Furthermore, in the dominant shoulder, the isometric ER strength was significantly reduced after the match (-4.8%; p = 0.012), whereas serve speed was not significantly reduced after match (-1.16%; p = 0.197). A single tennis match leads to significant reductions in shoulder ROM (e.g., IR of the dominant shoulder) and isometric strength (e.g., ER of the dominant shoulder). This study reveals the importance of recovery strategies prescription aiming at minimize post-match alteration in the shoulders.
... The tests were performed in the Exercise Physiology Laboratory of the Universidad Europea de Madrid (i.e., 600 m altitude). All evaluations were performed at the same time of day (i.e., evening, between 7:00 p.m. and 9:00 pm.) and under similar environmental conditions (i.e., 20-22 °C temperature, 60-65% relative humidity) to avoid effects associated with circadian rhythms on performance [22]. Days 2 and 3: Each group had to perform the same training session with compression garments (EXP) and without GCSs (CNT), with a recovery period of 72 h between the two sessions. ...
Article
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The aim of this study was to evaluate changes in electromyographic activity with the use of gradual compression stockings (GCSs) on middle-distance endurance athletes' performance, based on surface electromyography measurement techniques. Sixteen well-trained athletes were recruited (mean ± SD: age 33.4 ± 6.3 years, VO2max 63.7 ± 6.3 mL•kg −1 •min −1 , maximal aerobic speed 19.7 ± 1.5 km•h). The athletes were divided into two groups and were assigned in a randomized order to their respective groups according to their experience with the use of GCSs. Initially, a maximum oxygen consumption (VO2max) test was performed to standardize the athletes' running speeds for subsequent tests. Afterward, electromyographic activity, metabolic, and performance variables for each group were measured with surface electromyography. In addition, blood lactate concentration was measured, both with and without GCSs, during 10 min at 3% above VT2 (second ventilatory threshold), all of which were performed on the track. Next, surface electromyography activity was measured during a 1 km run at maximum speed. No significant changes were found in electromyography activity, metabolic and performance variables with GCSs use (p > 0.164) in any of the variables measured. Overall, there were no performance benefits when using compression garments against a control condition.
... During the second and third sessions, the participants carried out the experimental protocol, after ingesting either a BRJ supplement or a placebo (PLA). In line with previous studies on diurnal variation in strength and muscle power in RT, 36 and a study on the different effects of BRJ based on the time of day, 20 the experimental measurements were taken in the morning, at the same time of day (±0.5 h) for each individual, to standardize the influence of the circadian rhythm, at a temperature of 23°C (±1°C). This study was registered at ClinicalTrials.gov ...
Article
Background Beetroot juice (BRJ) is used as an ergogenic aid, but no previous study has analyzed the effect this supplement has on the production of explosive force and muscular endurance in physically active women. Hypothesis BRJ improves explosive force and muscular endurance in the lower limbs of physically active women. Study design Randomized double-blind crossover study. Level of evidence Level 3 Methods Fourteen physically active women performed a countermovement jump (CMJ) test, a back squat test for assessing velocity and power at 50% and 75% of one-repetition maximum (1RM), and the number of repetitions on a muscular endurance test consisting of 3 sets at 75% of 1RM in a resistance training protocol comprising 3 exercises (back squat, leg press, and leg extension). The participants performed the test in 2 sessions, 150 minutes after ingesting 70 mL of either BRJ (400 mg of nitrate) or a placebo (PLA). Results A greater maximum height was achieved in the CMJ after consuming BRJ compared with a PLA ( P = 0.04; effect size (ES) = 0.34). After a BRJ supplement at 50% 1RM, a higher mean velocity [+6.7%; P = 0.03; (ES) = 0.39 (–0.40 to 1.17)], peak velocity (+6%; P = 0.04; ES = 0.39 [−0.40 to 1.17]), mean power (+7.3%; P = 0.02; ES = 0.30 [−0.48 to 1.08]) and peak power (+6%; P = 0.04; ES = 0.20 [−0.59 to 0.98]) were attained in the back squat test. In the muscular endurance test, BRJ increased performance compared with the PLA ( P < 0.00; η p ² = 0.651). Conclusion BRJ supplements exert an ergogenic effect on the ability to produce explosive force and muscular endurance in the lower limbs in physically active women. Clinical relevance If physically active women took a BRJ supplement 120 minutes before resistance training their performance could be enhanced.
... Differences found for the Wingate test could be attributed to the effects of circadian rhythms. In this way, it has been proven that circadian rhythms affect different physiological variables that make physical performance in the early hours of the morning diminishing compared to that performed in the afternoon (Lopez-Samanes et al., 2017). Thus, in the Wingate test, lower values have been reported in the morning, and higher at noon (Souissi et al., 2013). ...
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The potential ergogenic effect of nutritional supplements depends on their dosage and the type of exercise executed. Aiming at reviewing the research literature regarding sport supplements utilized in judo in order to improve performance, a literature search was performed at the following databases: Dialnet, PubMed, Scielo, Scopus and SportDiscus. A total of 11 articles met the inclusion criteria and were selected. Evidence revised indicates that supplementation with caffeine, β-alanine, sodium bicarbonate, creatine, and β-hydroxy-β-methylbutyrate has a positive effect on judo-related performance. Moreover, there is evidence suggesting that combining some of these nutritional supplements may produce an additive effect.
... Top 150 41 57 8 7 The players were summoned at the same time of day to perform the tests [29]. First, a standardized 10-minute directed warm-up was performed consisting of joint mobility, linear movements with the chair, circular movements and turns simulating hitting, and low-intensity accelerations and decelerations [30]. ...
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The aim of this study was to identify the physical factors related to serve speed in male professional wheelchair tennis players (WT). Nine best nationally-ranked Spanish male wheelchair tennis players (38.35 ± 11.28 years, 63.77 ± 7.01 kg.) completed a neuromuscular test battery consisting of: isometric handgrip strength; serve velocity; 5, 10 and 20 m sprint (with and without racket); agility (with and without racket); medicine ball throw (serve, forehand and backhand movements); and an incremental endurance test specific to WT. Significantly higher correlations were observed in serve (r = 0.921), forehand (r = 0.810) and backhand (r = 0.791) medicine ball throws showing a positive correlation with serve velocity. A regression analysis identified a single model with the medicine ball throw serve as the main predictor of serve velocity (r2 = 0.847, p < 0.001). In conclusion, it is recommended that coaches and physical trainers include medicine ball throw workouts in the training programs of WT tennis players due to the transfer benefits to the serve speed.
... Isometric handgrip strength (HGS) was measured twice for the dominant hand using a calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan) with 30 s of passive recovery between trials. Participants sat with 0 • of shoulder flexion and elbow flexion, and the forearm and hand in a neutral position and exerted their maximal strength for 5 s [43]. The highest value of the dominant hand was recorded and used for statistical analysis as the maximum voluntary handgrip strength. ...
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Background: Beach handball (BH) is a sport in which sporting performance is influenced, together with team interaction, by individual performance in terms of strength. Body composition is one of the main factors for sports performance and eating habits can condition this variable. The Mediterranean diet (MD) can significantly reduce the risk of mortality or cardiovascular disease. In addition, the Spanish Ministry of Agriculture, Food and Environment carries out different campaigns to promote it among young athletes, establishing it as a suitable diet for sports. Objectives: The main aims of the study are to assess body composition, physical activity and adherence to the MD of beach handball players. It also aims to evaluate age group differences in male and female players, as well as studying the possible relationship between MD, body composition and performance variables. Methods: A total of 59 Spanish BH players were recruited in the national championship of BH in the province of Alicante. Thirty-eight male (14 junior; 17.0 ± 0.1 years and 24 seniors; 25.5 ± 4.7 years) and twenty-one female (7 junior; 16.1 ± 1.46 years and 14 seniors; 23.2 ± 2.0 years) BH players participated in this study. The questionnaire to evaluate eating habits was Mediterranean diet adherence (KIDMED). Body composition was measured with electrical bioimpedance. Strength was evaluated by means of a maximum isometric handgrip test of the dominant hand with handgrip and height of jump by counter-jump on contact platform. In the statistical analysis, descriptions and correlations between the study variables were made. Results: In females, when the adherence to the MD is lower, the weight is higher, the lean body mass is lower and worse results are observed in performance tests. As for males, there are differences in weight and lean body mass according to category. Conclusions: Adequate eating habits are related to the weight of beach handball athletes. In addition, specifically with junior players, it has been observed that adherence to the MD correlates with weight.
... The circadian rhythm in body temperature is known to relate to the diurnal variation in physical and sports performances. For example, diurnal variations in reaction time (Kleitman et al. 1938;Wright et al. 2002), grip strength (Edward et al. 2005), isometric knee extension torque (Guette et al. 2005), ball speed in tennis serves, jump height, sprint time, 10 km running time (López-Samanes et al. 2017), Wingate power (Souissi et al. 2007), and free-style swimming speed (Baxter and Reilly 1983; Kline et al. 2007) varied in time with the circadian rhythm in body temperature. ...
Article
This study aimed to test in elite athletes the correlation between the chronotype determined by the reduced version of the Morningness-Eveningness Questionnaire (rMEQ) and that determined by the Munich ChronoType Questionnaire (MCTQ). In total, 351 elite athletes filled out the rMEQ questionnaire, 59 athletes filled out the MCTQ questionnaire, and 39 athletes filled out both questionnaires. The rMEQ score and the corrected midpoint of sleep from the MCTQ correlated weakly (|r| = 0.360, p < .05); however, some cases were mismatched. The MSFsc also weakly correlated with age (|r| = 0.374, p < .05), while rMEQ did not. Our results may suggest that the choice of questionnaire to determine chronotype should depend on the purpose and the type of sport athlete.
... Numerous studies involving other sports specialties have noted also that the dynamic short-duration maximal exercise performances seem to oscillate consistently throughout the day, peaking in the evening (Mirizio et al. 2020). These maximal exercise performances included some representative protocols of movement patterns performed across handball matches (Mhenni et al. 2017;Pavlović et al. 2018), specific tasks for handball goalkeepers (Jarraya et al. 2013(Jarraya et al. , 2014a, swimming (Arnett 2002), tennis services (López-Samanes et al. 2017), cycling (Lericollais et al. 2009;Chtourou et al. 2011Chtourou et al. , 2013, jumping (Sedliak et al. 2008;Taylor et al., 2011 � ;Souissi et al. 2013 � � ), RSA (Racinais et al., � ) as well as other force-velocity-based trials (Souissi et al. 2010;López-Samanes et al. 2017). The available scientific data have provided several mechanisms that could occur individually or together and which could be the origin of such diurnal variations. ...
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The present study examined the effect of time-of-day in psychological responses and short-term maximal performances in elite male handball players. Eighteen male handball players performed, in a counterbalanced order and at three time-of-day (i.e., in the morning at 10:00 h, in the afternoon at 14:00 h and in the evening at 18:00 h) the Repeated Sprint Ability (RSA) and the Ball-Throwing Velocity (BTV) test. Profile of mood states (POMS), simple (SRT) and choice (CRT) reaction times, and Stroop test to evaluate selective attention (SA) and Hooper questionnaires were assessed before the physical tests. Oral temperature (OT) was measured in the beginning of each testing session. The results revealed, for the POMS questionnaire, that the negative mood-states (anxiety, anger, confusion, depression, and fatigue) were higher in the morning while positive mood-state (vigor) was higher in the evening. Also, SRT, CRT and SA were better in the evening. For physical tests, BTV and performance during the RSA test were also better in the evening. OT was higher in the evening than in the morning and the afternoon. The findings suggest that, in elite handball players, cognitive and short-term maximal physical performances were better increased during the day from the morning to the evening.
... Generally, there is a peak of athletic performance in the afternoon during which there is a peak of the fueling metabolic activity of physiological processes [14]. Athletes with a high evening or morning phenotype want to do better endurance activities [15], and strength training [16], near their circadian peak. According to Souissi et al. [17], and Bernard et al. [18] there was a significant circadian variation in maximal anaerobic power during Force Velocity and Wingate tests and Cycle and Multi-Jump tests. ...
... Various physiological and psychological functions have been shown to changes during the solar day (Atkinson & Reilly, 1996;Gueldich et al., 2019), and the existence of circadian rhythms in human performance is well established (Souissi, Gauthier, Sesboüé, Larue, & Davenne, 2004). The circadian rhythm of performance has received a great deal of attention (Atkinson & Reilly, 1996;Küüsmaa-Schildt et al., 2019;López-Samanes et al., 2017;Tiwari, & Deol, 2016), with evidence of changes in anaerobic physical performance with time of day Souissi et al., 2007;Souissi et al., 2010). Whereas, the literature generally indicates an early morning nadir and a peak performance in the late afternoon (Chtourou & Souissi, 2012). ...
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The aim of this study is to see whether Ramadan fasting has an effect on the diurnal variations in anaerobic power and swimming performance or not. Ten participants whose mean ± SE for age, height, body mass are 19.4 ± 1.4 years, 1.72 ± 0.1 m and 72.8 ± 6.6 kg, respectively. They are tested at 3 testing periods [i.e., one week before Ramadan (BR), the middle period of Ramadan (MPR), the end period of Ramadan (EPR)], tests are performed at 07:00 h and 17:00 h throughout every course. The test sessions were started with oral temperature and body mass measurements. Regularly doing first the Wingate test then a 25-m swim at maximal speed at each test session. During the three experimental periods, dietary intake was assessed. The result shows a significant diurnal variation of muscle power and fatigue throughout the Wingate test before Ramadan. Likewise, there is a daily rhythm in the stroke parameters and swimming performance in the mentioned period. These diurnal variations change during the month of Ramadan with a decrease in power output, swim performance, swim speed and stroke length in the evening, with no changes for the morning tests. Moreover, the diurnal variations of muscle fatigue during the three morning tests show no changes and remain the same. Whereas the three evening tests show a gradual increase towards tiredness. The results show that Ramadan may has a great effect on the circadian rhythm of muscle power and swimming performance. The time-of-day effects the anaerobic power variables during the normal days which disappear during Ramadan. Ramadan fasting effects performance in the evening; however, the morning performance tests are unchangeable during Ramadan. Additionally, Ramadan fasting has no adverse effect on energy intake, and percentages of macronutrient intake. Article visualizations: </p
... All exercise tests were conducted at the same time of day (± 2 h) to avoid circadian variations [27]. ...
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Objectives Little information is available regarding the effects of beetroot juice (BRJ) on muscle performance and contractions during resistance exercise. The muscle strength and power of the lower extremity is an important attribute in Taekwondo, therefore, present study examines the effects of 6 days of BRJ supplementations on muscle performance during isokinetic contractions of knee muscle in male Taekwondo athletes. Equipments and methods Twelve male Taekwondo athletes (age, 19.2 ± 1.6 yrs) were volunteered to take part in this double-blind, placebo-controlled, randomized crossover design. Participants consumed either 140 mL nitrate-rich concentrated BRJ (∼12.8 mmol NO3⁻) or placebo (blackcurrant juice) for six consecutive days. On the last day of supplementation, the knee extensions were performed on a Biodex isokinetic dynamometer. Treatment periods were separated by a 10-day washout periods. Results Knee extensor peak torque increased significantly (P < 0.05) following BRJ supplementation from 2.45 ± 0.19 to 2.60 ± 0.23 and from 1.89 ± 0.12 to 2.01 ± 0.18 Nm/kg at angular velocities of 180 and 360°/s, respectively in the dominant leg and it increased significantly (P < 0.05, from 2.04 ± 0.15 to 2.07 ± 0.24 Nm/kg) at 360°/s in the non-dominant. An increase in peak torque was also detected during 50 maximal knee extensions at 180°/s. Responses of blood pressure supplementation and placebo were not significantly different. It is concluded that short-term BRJ supplementation enhances bilateral muscle strength during highest velocities of isokinetic contractions and reduces fatigue during muscular contractions of knee extensor in male Taekwondo athletes.
... Numerous studies involving other sports specialties have noted also that the dynamic short-duration maximal exercise performances seem to oscillate consistently throughout the day, peaking in the evening (Mirizio et al. 2020). These maximal exercise performances included some representative protocols of movement patterns performed across handball matches (Mhenni et al. 2017;Pavlović et al. 2018), specific tasks for handball goalkeepers (Jarraya et al. 2013(Jarraya et al. , 2014, swimming (Arnett 2002), tennis services (López-Samanes et al. 2017), cycling (Lericollais et al. 2009;Chtourou et al. 2011Chtourou et al. , 2013, jumping (Sedliak et al. 2008;Souissi et al. 2013), RSA (Racinais et al., 2005) as well as other forcevelocity-based trials (Souissi et al. 2010;López-Samanes et al. 2017). The available scientific data have provided several mechanisms that could occur individually or together and which could be the origin of such diurnal variations. ...
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This study aims to assess: (i) the morning -to- evening variability in body temperature, ball throwing velocity (BTV), shooting address, explosive lower-body power, strength power, and the repeated sprint ability (RSA) among male handball players; and (ii) the diurnal variations according to players’ positions. Twenty-two participants assigned in players of thefront line (FL; N=11) and rear line (RL; N=11) completed assessments at 8:00 a.m. and 6:00 p.m., on two occasions dispersed throughout one week. Diurnal variations in BTV (p < 0.001), 1-RM Back Half Squat test (p < 0.001), and the counter movement jump (CMJ) test (p < 0.01) were recorded in the whole population. Specifically, morning -to- evening variabilities in BTV were noted in the FL (p < 0.05) and RL players (p < 0.001), with greater values observed in RL (p < 0.001). Significant variations were also observed in the 1-RM back half squat at RL (p < 0.01), and in CMJ (p < 0,01) and RSA (p < 0.05) at FL players. In conclusion, diurnal variations were higher in the evening compared to morning hours in players of RL in BTV and the explosive lower-body power, and in players of FL in CMJ and RSA performances.
... At the individual level, peak performance is also influenced by circadian phenotypes, including an individual's diurnal preference for morning or evening activity patterns [5,16] and chronotype, an individual's sleep-wake phenotype. Athletes with extreme morning or evening phenotypes tend to perform better near their circadian peak in endurance activities [5,12,28,26], as well as in strength training [6,13,32,10,21]. Interestingly, these diurnal effects may be strong enough to shape the distribution of circadian phenotypes in particular endurance sports that regularly compete in the morning; morning-types are more prevalent among elite runners, cyclists, and triathletes [23,20]. ...
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Although individual athletic performance generally tends to peak in the evening, individuals who exhibit a strong diurnal preference perform better closer to their circadian peak. Time-of-day performance effects are influenced by circadian phenotype (diurnal preference and chronotype—sleep-wake patterns), homeostatic energy reserves and, potentially, genotype, yet little is known about how these factors influence physiological effort. Here, we investigate the effects of time of day, diurnal preference, chronotype, and PER3 (a circadian clock gene) genotype on both effort and performance in a population of Division I collegiate swimmers (n = 27). Participants competed in 200m time trials at 7:00 and 19:00 and were sampled pre- and post-trial for salivary α-amylase levels (as a measure of physiological effort), allowing for per-individual measures of performance and physiological effort. Hair samples were collected for genotype analysis (a variable-number tandem-repeat (VNTR) and a single nucleotide polymorphism (SNP) in PER3). Our results indicate significant and parallel time-of-day by circadian phenotype effects on swim performance and effort; evening-type swimmers swam on average 6% slower with 50% greater α-amylase levels in the morning than they did in the evening, and morning types required 5–7 times more effort in the evening trial to achieve the same performance result as the morning trial. In addition, our results suggest that these performance effects may be influenced by gene (circadian clock gene PER3 variants) by environment (time of day) interactions. Participants homozygous for the PER34,4 length variant (rs57875989) or who possess a single G-allele at PER3 SNP rs228697 swam 3–6% slower in the morning. Overall, these results suggest that intra-individual variation in athletic performance and effort with time of day is associated with circadian phenotype and PER3 genotype.
... A calibrated handgrip dynamometer (Takei 5101, Tokyo, Japan) was used to measure isometric grip strength (HGS), the test was performed twice for the dominant hand. Participants sat with 0 • of shoulder and elbow flexion, and the forearm and hand in neutral position, and exerted their maximal force for 5 s [27], with 30 s of passive recovery between trials. The highest value for both hands was recorded and used for statistical analysis as the maximum voluntary hand grip strength. ...
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Celiac disease (CD) is an autoimmune disease characterized by gluten-induced intestinal inflammation. Dietary restrictions and symptoms may have a significant impact on the patient's quality of life, body composition (BC), and strength. This study was designed to assess the impact of an isocaloric gluten free diet and resistance exercise in women. A total of 28 Spanish women, aged 40 years old or more, took part in a randomized controlled trial. Each group received a different intervention: group 1, gluten-free nutrition plan + exercise (GFD + E); group 2, gluten-free nutrition plan (GFD); group 3, celiac controls (NO-GFD); and group 4, non-celiac controls (CONTROL). The variables studied were quality of life, BC and isometric hand strength. After 12 weeks of intervention, celiac women that followed a gluten-free diet and exercise showed higher scores on the psychological health scale than celiac women without intervention. The women in group 1 were the only ones who presented improvements in BC variables; fat mass, BMI, and fat-free mass. Negative correlations were found between the perception of quality of life and age, however a positive correlation between quality of life and isometric strength test results was found. In addition to a gluten-free diet, resistance training is essential to improve BC, strength, and gastrointestinal symptoms.
... It has been previ- Running distance and asymmetry data are reported as mean±standard deviation. ously reported that athletes perform better in the evenings than in the mornings in respect of performance parameters such as agility, sprint, reactive force and jump (16)(17)(18). This situation is similar in terms of high speed running distance in our study. ...
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Purpose: Although there are many studies in the literature regarding the running of soccer players, there is a need to examine the running asymmetry of the athletes' actual training, regardless of a specific intervention protocol. The aim of this study was to compare the running asymmetry of healthy elite soccer players in training sessions at different times of the day. Methods: Sixteen healthy male elite soccer players were included in this study. Global Positioning System units (GPSports, SPI Pro, 5 Hz, GPSport, Canberra, Australia) were used to define training and running details. Fourteen (7 morning, 7 evening) training data were evaluated. Results: There was no statistical difference between morning and evening trainings in terms of training time, heart rate average and total running distance except for high speed running distance. Running asymmetry was 66% greater in evening training sessions than in morning training sessions (p=0.001; 4.13±1.92, 2.49±1.32 respectively). Running asymmetry did not show any significant correlation with training time, heart rate average, running distance, and high speed running distance (p>0.05). Conclusion: Running asymmetry is higher in evening training sessions than in morning training sessions. Therefore, for athletes who are particularly at high risk of injury or who are in the process of a return to sports, and from whom high performance is not expected, morning trainings may be preferred instead of evening trainings. If training can not be performed in the morning, clinicians should follow the athletes instantly during evening training
... Circadian rhythm have been observed to influence exercise performance, with some studies showing greater performance in the late afternoon (16:00-20:00 h) compared with the morning (07:00-10:00 h) (Reilly and Waterhouse 2009), specifically influencing neuromuscular (Mora- Rodriguez et al. 2012;Lopez-Samanes et al. 2017), Wingate test (Souissi et al. 2004;Souissi et al. 2007) and repeated sprint performances (Racinais et al. 2005a;Giacomoni et al. 2006; Racinais et al. 2010). The influence of circadian rhythm on exercise performance is paralleled by changes in body temperature (Atkinson and Reilly 1996). ...
Article
Purpose: The aim of this study was to evaluate if caffeine can reduce the negative influence of diurnal variations on repeated-sprint performance, in addition to investigating if caffeine in the afternoon would potentiate performance compared to the morning. Methods: Thirteen physically active men took part in this randomized, double-blind, placebo-controlled and crossover study. All participants underwent a repeated-sprint ability test (10 x 6s cycle sprints, with 30s of rest) 60 min after ingestion of either 5 mg·kg-1 or placebo under four different conditions: morning with caffeine ingestion (AMCAF); morning with placebo ingestion (AMPLA); afternoon with caffeine ingestion (PMCAF) and afternoon with placebo ingestion (PMPLA). Total work, peak power (PP) and anaerobic power reserve (APR) were assessed. Results: Oxygen consumption (VO2), heart rate (HR), lactate concentration ([La-]) and rating of perceived exertion (RPE) were also measured during the repeated-sprint test. Total work (+ 8%, d = 0.2, small), PP (+ 6%, d = 0.2) and APR (+ 9%, d = 0.2) were significantly higher in the afternoon when compared to morning. However, physiological responses were not different between caffeine and placebo conditions. Conclusion: Repeated-sprint (10 x 6s cycle sprint) performance was influenced by time of day, with lower performance in the morning compared with the afternoon. However, caffeine supplementation did not prevent the reduction in performance in the morning or improve performance in the afternoon.
... Numerous studies involving other sports specialties have noted also that the dynamic short-duration maximal exercise performances seem to oscillate consistently throughout the day, peaking in the evening (Mirizio et al. 2020). These maximal exercise performances included some representative protocols of movement patterns performed across handball matches (Mhenni et al. 2017;Pavlović et al. 2018), specific tasks for handball goalkeepers (Jarraya et al. 2013(Jarraya et al. , 2014, swimming (Arnett 2002), tennis services (López-Samanes et al. 2017), cycling (Lericollais et al. 2009;Chtourou et al. 2011Chtourou et al. , 2013, jumping (Sedliak et al. 2008;Souissi et al. 2013), RSA (Racinais et al., 2005) as well as other forcevelocity-based trials (Souissi et al. 2010;López-Samanes et al. 2017). The available scientific data have provided several mechanisms that could occur individually or together and which could be the origin of such diurnal variations. ...
... However, it revealed that isometric grip strength (IS) was not affected by the time of day. 33 The results of the literature and the results of our research are similar in terms of the negative effect of morning performance on agility and vertical jump performance. In addition, it should be kept in mind that the circadian differences, current fitness levels, changes in sleep levels and training histories of the volunteers participating in the studies with different results from our study may be different ...
... Calibration was performed according to the manufacturer's specifications prior to each test. The serve test procedure was conducted as previously reported elsewhere [22]. Briefly, the radar was positioned in the tennis court on the center of the baseline, 4 m behind the server, aligned with the approximate height of ball contact (~2.2 m) and pointing down the center of the court. ...
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Shoulder pain has been associated with glenohumeral internal rotation deficit (GIRD) and a reduction in external rotation (ER) strength; however, in tennis players, there is scarce evidence regarding the impact of a single match on shoulder range of motion (ROM), strength and serve speed. The aim of this study was to determine the acute effect of a single tennis match on shoulder rotation ROM, isometric strength and serve speed. Twenty-six professional tennis players participated in the study (20.4±4.4 years; 10.5±3.2 years tennis expertise; 20.5±5.4 h/week training). Passive shoulder external (ER-ROM) and internal rotation ROM (IR-ROM), ER and IR isometric strength were measured before and after a single tennis match (80.3±21.3 min) in both shoulder´s. Moreover, the total arc of motion (TAM) and ER/IR strength ratio were calculated. Video analysis was used to assess the number of serves and groundstrokes, while a radar gun was utilized to measure maximal ball speed. In the dominant shoulder, compared to pre-match levels, IR-ROM was significantly reduced (-1.3%; p = 0.042), while ER-ROM (5.3%; p = 0.037) and TAM (3.1%; p = 0.050) were significantly increased. In the non-dominant shoulder, ER-ROM (3.7%; p = 0.006) was increased. Furthermore, in the dominant shoulder, the isometric ER strength was significantly reduced after the match (-4.8%; p = 0.012), whereas serve speed was not significantly reduced after match (-1.16%; p = 0.197). A single tennis match leads to significant reductions in shoulder ROM (e.g., IR of the dominant shoulder) and isometric strength (e.g., ER of the dominant shoulder). This study reveals the importance of recovery strategies prescription aiming at minimize post-match alteration in the shoulders.
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Tensiomyography (TMG) is a non-invasive technique commonly used for evaluating muscle properties in highly trained athletes. The aim of our study was to evaluate the mechanical characteristics of m. triceps surae in competitive runners through TMG measurement and analyze if there was a relationship with running economy (RE). Nine male runners completed the study (mean±SD: age 40.4±9.0 years, body height 176.2±4.9 cm, body mass 70.7±9.4 kg, 10-km time 39.8±5.9 min, VO 2peak 56.9 ± 6.5 mL kg-1 min-1). Each subject visited the lab on two occasions with 72h of rest between the trials. On the first day, an incremental test was performed to determine their ventilatory thresholds and peak oxygen consumption. On the second day, RE was evaluated on a treadmill at the velocity of their first ventilatory threshold (VT1), and mechanical characteristics of the soleus and gastrocnemius muscles were analyzed with TMG. Significant differences were found between the economic and non-economic runners in m. soleus in delayed time (Td), contraction time (Tc), and maximal radial displacement of the muscle belly (Dm). Also, significant differences were found in contraction time (Tc) in medium calf (MC) and in half relaxation time (Tr) in lateral twin (LT). The main finding of our study was that the runners with better RE showed greater stiffness in the triceps surae muscles, an aspect that seems to be associated with better performance in athlete runners.
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Introduction:Tennis is characterized by a large number of competitions and little recovery time between them. Thus, tennis players and coaching staff have become interested in the role that nutrition can play in maximizing sports performance. The scientific literature does not have recent narrative and/or systematic reviews about to nutrition in tennis. The aim of this study is to map, describe and discuss the state of the science of nutrition and dietetic practices for tennis players from a theoretical and contextual point of view, to enable focused future systematic reviews. Material and methods: A narrative review through the Dialnet, Elsevier, Medline, Pubmed and Web of Science databases, through a search strategy based on keywords separated by Boolean connectors. A series of inclusion / exclusion criteria were applied to select those investigations that responded to the aim of the work. Results: Nutritional recommendations on carbohydrate intake depend on the training load, 5-7 g/kg/day g/kg/day for normal training and 7-10 g/kg/day for competitive periods or high training load. The recommended protein intake is 1.8 g/kg/day and 1 g/kg/day of lipids. The supplements that can optimize tennis performance are caffeine, sodium bicarbonate, creatine and -alanine. Beetroot juice can be a possible aid to consider in dietetic-nutritional planning in tennis players. Conclusions: Performance and health of tennis player can be optimized, as well as adequate periodization of nutrients and supplements, meeting to the physiological demands of tennis.
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Objective Beetroot juice is a source of dietary nitrate (NO3-) recognized as a potential ergogenic aid to enhance tolerance during endurance exercise of submaximal-to-maximal intensity. However, little is known about the effects of beetroot juice on exercise performance in intermittent sports such as tennis. The present study aimed to determine the effect of acute beetroot juice supplementation on movement patterns during a competitive tennis match in professional players. Methods In a double-blind and randomized experiment, nine professional tennis players performed two experimental trials 3 h after ingesting either 70 mL of a commercially-available concentrated beetroot juice (6.4 mmol NO3-) or placebo (0.005 mmol NO3-). In each experimental trial, players completed a 3-set tennis match and two performance tests (i.e., serve speed and isometric handgrip strength) before and after the match. Match-play running performance was recorded using wearable GPS and accelerometer units. Results In comparison to the placebo trial, the acute beetroot juice supplementation did not modify any match-play running performance (p = 0.178 to 0.997, d = 0.01 to 0.42). Furthermore, beetroot juice supplementation did not alter the pre-to-post match change in serve speed (p = 0.663, ηp ² = 0.03) or isometric handgrip strength (p = 0.219, ηp ² = 0.18). Conclusions The current results indicated that acute ingestion of a commercialized shot of nitrate-rich beetroot juice (70 mL containing 6.4 mmol of NO3-) did not produce any performance benefit on tennis matchplay. Thus, acute beetroot juice supplementation seems an ergogenic aid with little value to enhance physical performance in professional tennis players.
Article
Objective: The aim of this study was to compare the potential post-activation performance enhancement (PAPE) effects of two different warm-up strategies, involving dynamic stretching (DS) or heavy load leg press (HL) on several key physical qualities in tennis players. Methods: Twenty-six elite male tennis players (age: 19.22 ± 4.20 years; body mass: 67.37 ± 8.19 kg; height: 1.77 ± 0.07 m) performed both warm-ups, with 48-hours between protocols (DS and HL), performed in a randomized order. Pre- and post-tests included: countermovement jump, 5-m and 10-m sprint, 5-0-5 agility test, and hip extension and flexion range-of-motion which were performed before and after DS and HL warm-up protocols. Results: The DS warm-up led to substantial improvements in 5-m and 10-m sprint, 5-0-5 agility test, countermovement jump, and also to higher hip flexion range-of-motion. The HL warm-up caused impairments in 5-m and 10-m sprints, but improvements in 5-0-5 agility test, countermovement jump and hip extension range-of-motion. Compared to HL, DS warm-up induced possibly to likely positive effects on 5-m and 10-m linear sprint performance, as well as in hip flexion range-of-motion. Nevertheless, no differences in performance improvements in 5-0-5 agility test, countermovement jump and hip extension range-of-motion were found when comparing DS and HL warm-up protocols. Conclusion: DS seems to be more effective than HL when performing a short warm-up protocol in elite tennis players.
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The primary aims of the present study were to examine the impact of chronotype on sleep/wake behaviour, perceived exertion, and training load among professional footballers. Thirty-six elite female professional football player’s (mean ± SD: age, 25 ± 4 y; weight, 68 ± 7 kg) sleep and training behaviours were examined for 10 consecutive nights during a pre-season period using a self-report online player-management system and wrist activity monitors. All athletes completed the Morningness-Eveningness Questionnaire (rMEQ) on the first day of data collection. Eleven participants were morning types, seventeen participants were intermediate types, and three participants were evening types. Separate linear mixed models were conducted to assess differences in sleep, perceived exertion, and training behaviours between chronotype groups. Morning types woke up earlier (wake time: 07:19 ± 01:16 vs. 07:53 ± 01:01, p = 0.04) and reported higher ratings of perceived exertion compared to intermediate types (6.7 ± 1.1 vs. 5.9 ± 1.2, p = 0.01). No differences were observed between chronotype groups for bedtime, time in bed, total sleep time, sleep efficiency, training duration, or training load. In circumstances where professional female football players are required to train at a time opposing their natural circadian preference (e.g., morning type training in the evening), their perceived exertion during training may be higher than that of players that are training at a time that aligns with their natural circadian preference (e.g., evening type training in the evening). It is important for practitioners to monitor individual trends in training variables (e.g., rating of perceived exertion, training load) with relation to athlete chronotype and training time. Future research should examine the relationship between chronotype, training time, and rating of perceived exertion across different training durations.
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Numerous functional measures related to anaerobic performance display daily variation. The diversity of tests and protocols used to assess anaerobic performance related to diurnal effects and the lack of a standardized approach have hindered agreement in the literature. Therefore, the aim of the present study was to investigate and systematically review the evidence relating to time-of-day differences in anaerobic performance measures. The entire content of PubMed (MEDLINE), Scopus, SPORTDiscus® (via EBSCOhost) and Web of Science and multiple electronic libraries were searched. Only experimental research studies conducted in male adult participants aged ≥ 18 yrs before May 2021 were included. Studies assessing tests related to anaerobic capacity or anaerobic power between a minimum of two time-points during the day (morning vs evening) were deemed eligible. The primary search revealed that a total of 55 out of 145 articles were considered eligible and subsequently included. Thirty-nine studies assessed anaerobic power and twenty-five anaerobic capacity using different modes of exercise and test protocols. Forty-eight studies found several of their performance variables to display time-of-day effects, with higher values in the evening than the morning, while seven studies did not find any time-of-day significance in any variables which were assessed. The magnitude of difference is dependent on the modality and the exercise protocol used. Performance measures for anaerobic power found jump tests displayed 2.7 to 12.3% differences, force velocity tests ~8% differences, sprint tests 2.7 to 11.3% differences and 5-m multiple shuttle run tests 3.7 to 13.1% differences in favour of the evening. Performance measures for anaerobic capacity found Wingate test to display 1.8 to 11.7% differences and repeated sprint tests to display 3.4 to 10.2% differences. The only test not to display time-of-day differences was the running based anaerobic sprint test (RAST). Time-of-day variations in anaerobic performance has previously been partially explained by higher core-body and/or muscle temperature and better muscle contractile properties in the afternoon, although recent findings suggest that differences in methodology, motivation/arousal, habitual training times and chronotypes could provide additional explanations. There is a clear demand for a rigorous, standardised approach to be adopted by future investigations which control factors that specifically relate to investigations of time-of-day.
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Background It is habitual for combat sports athletes to lose weight rapidly to get into a lower weight class. Fluid restriction, dehydration by sweating (sauna or exercise) and the use of diuretics are among the most recurrent means of weight cutting. Although it is difficult to dissuade athletes from this practice due to the possible negative effect of severe dehydration on their health, athletes may be receptive to avoid weight cutting if there is evidence that it could affect their muscle performance. Therefore, the purpose of the present study was to investigate if hypohydration, to reach a weight category, affects neuromuscular performance and combat sports competition results. Methods We tested 163 (124 men and 39 woman) combat sports athletes during the 2013 senior Spanish National Championships. Body mass and urine osmolality (UOSM) were measured at the official weigh-in (PRE) and 13–18 h later, right before competing (POST). Athletes were divided according to their USOM at PRE in euhydrated (EUH; UOSM 250–700 mOsm · kgH2O−1), hypohydrated (HYP; UOSM 701–1080 mOsm · kgH2O−1) and severely hypohydrated (S-HYP; UOSM 1081–1500 mOsm · kgH2O−1). Athletes’ muscle strength, power output and contraction velocity were measured in upper (bench press and grip) and lower body (countermovement jump - CMJ) muscle actions at PRE and POST time-points. Results At weigh-in 84 % of the participants were hypohydrated. Before competition (POST) UOSM in S-HYP and HYP decreased but did not reach euhydration levels. However, this partial rehydration increased bench press contraction velocity (2.8-7.3 %; p < 0.05) and CMJ power (2.8 %; p < 0.05) in S-HYP. Sixty-three percent of the participants competed with a body mass above their previous day’s weight category and 70 of them (69 % of that sample) obtained a medal. Conclusions Hypohydration is highly prevalent among combat sports athletes at weigh-in and not fully reversed in the 13–18 h from weigh-in to competition. Nonetheless, partial rehydration recovers upper and lower body neuromuscular performance in the severely hypohydrated participants. Our data suggest that the advantage of competing in a lower weight category could compensate the declines in neuromuscular performance at the onset of competition, since 69 % of medal winners underwent marked hypohydration.
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The purpose of this study was to examine whether time of day variations in power output can be accounted for by the diurnal fluctuations existent in body temperature. 8 recreationally trained males (29.8±5.2 yrs; 178.3±5.2 cm; 80.3±6.5 kg) were assessed on 4 occasions following a: (a) control warm-up at 8.00 am; (b) control warm-up at 4.00 pm; (c) extended warm-up at 8.00 am; and, (d) extended warm-up at 4.00 pm. The control warm-up consisted of dynamic exercises and practice jumps. The extended warm-up incorporated a 20 min general warm-up on a stationary bike prior to completion of the control warm-up, resulting in a whole body temperature increase of 0.3±0.2°C. Kinetic and kinematic variables were measured using a linear optical encoder attached to a barbell during 6 loaded counter-movement jumps. Results were 2-6% higher in the afternoon control condition than morning control condition. No substantial performance differences were observed between the extended morning condition and afternoon control condition where body temperatures were similar. Results indicate that diurnal variation in whole body temperature may explain diurnal performance differences in explosive power output and associated variables. It is suggested that warm-up protocols designed to increase body temperature are beneficial in reducing diurnal differences in jump performance.
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This investigation aimed to quantify the typical variation for kinetic and kinematic variables measured during loaded jump squats. Thirteen professional athletes performed six maximal effort countermovement jumps on four occasions. Testing occurred over 2 d, twice per day (8 AM and 2 PM) separated by 7 d, with the same procedures replicated on each occasion. Jump height, peak power (PP), relative peak power (RPP), mean power (MP), peak velocity (PV), peak force (PF), mean force (MF), and peak rate of force development (RFD) measurements were obtained from a linear optical encoder attached to a 40 kg barbell. A diurnal variation in performance was observed with afternoon values displaying an average increase of 1.5-5.6% for PP, RPP, MP, PV, PF, and MF when compared with morning values (effect sizes ranging from 0.2-0.5). Day to day reliability was estimated by comparing the morning trials (AM reliability) and the afternoon trials (PM reliability). In both AM and PM conditions, all variables except RFD demonstrated coefficients of variations ranging between 0.8-6.2%. However, for a number of variables (RPP, MP, PV and height), AM reliability was substantially better than PM. PF and MF were the only variables to exhibit a coefficient of variation less than the smallest worthwhile change in both conditions. Results suggest that power output and associated variables exhibit a diurnal rhythm, with improved performance in the afternoon. Morning testing may be preferable when practitioners are seeking to conduct regular monitoring of an athlete's performance due to smaller variability.
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Circadian rhythm has an influence on several physiological functions that contribute to athletic performance. We tested the hypothesis that circadian rhythm would affect blood pressure (BP) responses but not O(2) uptake (Vo(2)) kinetics during the transitions to moderate and heavy cycling exercises. Nine male athletes (peak Vo(2): 60.5 ± 3.2 ml·kg(-1)·min(-1)) performed multiple rides of two different cycling protocols involving sequences of 6-min bouts at moderate or heavy intensities interspersed by a 20-W baseline in the morning (7 AM) and evening (5 PM). Breath-by-breath Vo(2) and beat-by-beat BP estimated by finger cuff plethysmography were measured simultaneously throughout the protocols. Circadian rhythm did not affect Vo(2) onset kinetics determined from the phase II time constant (τ(2)) during either moderate or heavy exercise bouts with no prior priming exercise (τ(2) moderate exercise: morning 22.5 ± 4.6 s vs. evening 22.2 ± 4.6 s and τ(2) heavy exercise: morning 26.0 ± 2.7 s vs. evening 26.2 ± 2.6 s, P > 0.05). Priming exercise induced the same robust acceleration in Vo(2) kinetics during subsequent moderate and heavy exercise in the morning and evening. A novel finding was an overshoot in BP (estimated from finger cuff plethysmography) in the first minutes of each moderate and heavy exercise bout. After the initial overshoot, BP declined in association with increased skin blood flow between the third and sixth minute of the exercise bout. Priming exercise showed a greater effect in modulating the BP responses in the evening. These findings suggest that circadian rhythm interacts with priming exercise to lower BP during exercise after an initial overshoot with a greater influence in the evening associated with increased skin blood flow.
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It is unclear how physical attributes influence tennis-specific performance in teenage players. The aims of this study were (a) to examine the relationships between speed, explosive power, leg stiffness, and muscular strength of upper and lower limbs; and (b) to determine to what extent these physical qualities relate to tournament play performance in a group of competitive teenage tennis players. A total of 12 male players aged 13.6 +/- 1.4 years performed a series of physical tests: a 5-m, 10-m, and 20-m sprint; squat jump (SJ); countermovement jump (CMJ); drop jump (DJ); multi-rebound jumps; maximum voluntary contraction of isometric grip strength; and plantar flexor of the dominant and nondominant side. Speed (r = 0.69, 0.63, and 0.74 for 5-, 10-, and 20-m sprints, respectively), vertical power abilities (r = -0.71, -0.80 and -0.66 for SJ, CMJ, and DJ, respectively), and maximal strength in the dominant side (r = -0.67 and -0.73 for handgrip and plantar flexor, respectively) were significantly correlated with tennis performance. However, strength in the nondominant side (r = -0.29 and -0.42 for handgrip and plantar flexor) and leg stiffness (r = -0.15) were not correlated with the performance ranking of the players. It seems that physical attributes have a strong influence on tennis performance in this age group and that an important asymmetry is already observed. By monitoring regularly such physical abilities during puberty, the conditioning coach can modify a program to compensate for the imbalances. This would in turn minimize the risks of injuries during this critical period.
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An English language self-assessment Morningness-Eveningness questionnaire is presented and evaluated against individual differences in the circadian vatiation of oral temperature. 48 subjects falling into Morning, Evening and Intermediate type categories regularly took their temperature. Circadian peak time were identified from the smoothed temperature curves of each subject. Results showed that Morning types and a significantly earlier peak time than Evening types and tended to have a higher daytime temperature and lower post peak temperature. The Intermediate type had temperatures between those of the other groups. Although no significant differences in sleep lengths were found between the three types, Morning types retired and arose significantly earlier than Evening types. Whilst these time significatly correlated with peak time, the questionnaire showed a higher peak time correlation. Although sleep habits are an important déterminant of peak time there are other contibutory factors, and these appear to be partly covered by the questionnaire. Although the questionnaire appears to be valid, further evaluation using a wider subject population is required.
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The purpose of this study was to determine whether metabolic and cardiorespiratory adaptations to exercise training are greater at the time of day of training than at another time. Twenty-seven subjects performed cycle ergometer tests in the morning (AM) and in the afternoon (PM) before and after a 6-wk period during which ten subjects trained regularly in the morning, seven subjects trained in the afternoon, and ten did not train. Training caused decreases in HR, VE, and rating of perceived exertion during submaximal exercise; a 7.7% increase (p less than 0.01) in VO2 max; and a 9.1% increase (p less than 0.01) in performance time. Adaptations (training effects) were independent of time of day of training for all variables except VO2 at the ventilatory threshold. Compared with each other, subjects who trained in the morning had relatively higher post-training thresholds in the morning, while subjects who trained in the afternoon had relatively higher values in the afternoon (p less than 0.05). This is evidence of circadian specificity in training and supports the notion of planning physical preparation to coincide with the time of day at which one's critical performance is scheduled.
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Thermal stress is known to impair endurance capacity during moderate prolonged exercise. However, there is relatively little available information concerning the effects of thermal stress on the performance of high-intensity short-duration exercise. The present experiment examined human power output during repeated bouts of short-term maximal exercise. On two separate occasions, seven healthy males performed two 30-s bouts of sprint exercise (sprints I and II), with 4 min of passive recovery in between, on a cycle ergometer. The sprints were performed in both a normal environment [18.7 (1.5) degrees C, 40 (7)% relative humidity (RH; mean SD)] and a hot environment [30.1 (0.5) degrees C, 55 (9)% RH]. The order of exercise trials was randomised and separated by a minimum of 4 days. Mean power, peak power and decline in power output were calculated from the flywheel velocity after correction for flywheel acceleration. Peak power output was higher when exercise was performed in the heat compared to the normal environment in both sprint I [910 (172) W vs 656 (58) W; P < 0.01] and sprint II [907 (150) vs 646 (37) W; P < 0.05]. Mean power output was higher in the heat compared to the normal environment in both sprint I [634 (91) W vs 510 (59) W; P < 0.05] and sprint II [589 (70) W vs 482 (47) W; P < 0.05]. There was a faster rate of fatigue (P < 0.05) when exercise was performed in the heat compared to the normal environment. Arterialised-venous blood samples were taken for the determination of acid-base status and blood lactate and blood glucose before exercise, 2 min after sprint I, and at several time points after sprint II. Before exercise there was no difference in resting acid-base status or blood metabolites between environmental conditions. There was a decrease in blood pH, plasma bicarbonate and base excess after sprint I and after sprint II. The degree of post-exercise acidosis was similar when exercise was performed in either of the environmental conditions. The metabolic response to exercise was similar between environmental conditions; the concentration of blood lactate increased (P < 0.01) after sprint I and sprint II but there were no differences in lactate concentration when comparing the exercise bouts performed in a normal and a hot environment. These data demonstrate that when brief intense exercise is performed in the heat, peak power output increases by about 25% and mean power output increases by 15%; this was due to achieving a higher pedal cadence in the heat.