Prolonged cognitive effort impairs inhibitory control and causes significant mental fatigue after an endurance session with an auditive distractor in professional soccer players.

BACKGROUND: Throughout official soccer matches, the presence of cheer by the crowd could be considered a critical auditive distraction that could further impair the cognitive interference control system, multiple object tracking (MOT) skill, heart rate variability (HRV), and increase mental fatigue. As the resource is not immediately replenished, the impairment of the cognitive interference control system may be delayed following a soccer game. Then, evaluating the recovery time course of the cognitive interference control system, MOT skill, HRV, and mental fatigue after prolonged tasks combining physical, endurance, and cognitive effort are essential. PURPOSE: We aimed to analyze the acute effect of cognitive effort and auditive distractor with 24-h follow-up throughout a prolonged endurance session on inhibitory control, subjective mental fatigue, MOT skill, and HRV in professional soccer players. METHODS: Twenty professional male soccer players were recruited (23.56 ± 3.8 years, 78.1 ± 6.9 kg, 1.77 ± 0.06 m, and 12.5 ± 5.3% body fat). The sessions were performed in a randomized and counterbalanced crossover design, divided into four experimental conditions: endurance, endurance + MOT, endurance + MOT + AD, and endurance + AD. The soccer players completed the incongruent Stroop task utilizing an eye-tracker to assess cognitive effort. MOT task, subjective mental fatigue, and HRV were evaluated before the endurance training (60%Δ of maximal aerobic velocity during 40-min) and after 30-min and 24-h of recovery. These sessions were designed to investigate the acute effect of prolonged cognitive effort (repeated MOT throughout the endurance task) and AD (constant crowd noise and coach's voice each 15-40 s, totalizing = 80 voices) on inhibitory control, MOT skills, HRV, and subjective mental fatigue after a fixed endurance training session. RESULTS: There was no condition × time interaction for accuracy of inhibitory control (p > 0.05, ηp2 = 0.001). There was a significant condition × time interaction for inhibitory control response time (p < 0.05, ηp2 = 0.16). A higher response time of inhibitory control was found for the endurance + MOT + AD and endurance + MOT experimental sessions (p < 0.05). There was a significant condition × time interaction for subjective mental fatigue (p < 0.05, ηp2 = 0.46). A higher subjective mental fatigue was found for the endurance + MOT + AD and endurance + MOT experimental sessions (p < 0.05). There was no condition × time interaction for HRV (p > 0.05, ηp2 = 0.02). CONCLUSION: We concluded that cognitive effort throughout a prolonged endurance session impaired inhibitory control and increased mental fatigue without promoting greater MOT skill and HRV changes in professional soccer players.

Repeated stroboscopic vision training improves anticipation skill without changing perceptual-cognitive skills in soccer players.

In this study we aimed to analyze the repeated effect of stroboscopic vision training on perceptual-cognitive skills in soccer players. A total of 28 male soccer players participated in this experimental and randomized study with parallel groups. The soccer players were pair-matched according to perceptual-cognitive skills and randomized into two groups: Stroboscopic vision training and Control. Multiple object tracking, anticipation, and decision-making skills were measured before and after the 8-week intervention. An increase in multiple object tracking (p < 0.05) and decision-making skills (p < 0.05) from baseline to post-experiment was found in both groups without main group effect (p > 0.05). The findings showed an increase in anticipation skill from baseline to post-experiment in both groups (p < 0.05), with higher anticipation skill for the stroboscopic group than in the control group post-experiment (p < 0.05). Thus, we conclude that repeated stroboscopic vision training could improve anticipation skill in soccer athletes.

Acute Effects of Different Conditioning Activities on Amateur Soccer Players.

Several warm-up activities are used to prepare soccer players for training and games. However, few studies have focused on comparing different activities (strength vs. stretching) in young and amateur athletes, especially for performance improvement in explosive actions. Thus, in order to compare the effect of four conditioning activities on jump and sprint performances, 12 soccer athletes (age: 19±0.8; weight (kg): 72.8±8.0; height (cm): 180±6.7) performed four warm-up activities: strength exercise (cluster system), combined exercise, plyometric exercise, and static stretching (control). The countermovement jump (CMJ) and 30-meter run (30-m Sprint) were performed 10 min after each experimental condition. A ONE-WAY ANOVA test of repeated measures was conducted with a Tukey's post-hoc test to compare the conditions. The strength conditioning activity protocol (33.68±2.87) showed a significant difference for the CMJ from static stretching (30.96±3.16) (p>0.05). There were significant differences regarding the 30-m Sprint test between strength conditioning (4.72±0.19) and combined activities (4.71±0.21) compared to static stretching (4.84±0.21) (p>0.05). In conclusion, the combined conditioning activity and strength protocols can be chosen in warm-up activities instead of static stretching (control condition) for improved immediate sprint and jump abilities in amateur soccer players.

Can Prolongate Use of Social Media Immediately Before Training Worsen High Level Male Volleyball Players' Visuomotor Skills?

Our aim was to analyze the effect of mental fatigue caused by prolonged social media use on high-level volleyball players' visuomotor skills. Eighteen high-level male young volleyball players participated in this randomized, counterbalanced, crossover design. All participants underwent a 2-week experiment in which we measured their response times when performing a visuomotor task with and without mental fatigue inducement through repeated use of social media immediately before training sessions. In the control condition, participants watched TV for 30-minutes, and in the social media condition, they used a social media app (Instagram®) on smartphones for 30-minutes. We found a significant Condition x Time interaction on visuomotor task response time (p = 0.03), but there was no significant main effect of either Time or Condition. Mental fatigue, induced by repeated app-based social media use for 30-minutes immediately before training sessions, affected elite male volleyball players' visuomotor skills.

Brain Stimulation Over the Motion-Sensitive Midtemporal Area Reduces Deleterious Effects of Mental Fatigue on Perceptual-Cognitive Skills in Basketball Players.

The objective of this study was to analyze the effect of anodal transcranial direct current stimulation (a-tDCS) over the motion-sensitive midtemporal area on perceptual-cognitive skills (visuomotor and basketball decision-making skills) in mentally fatigued basketball players. A total of 20 male basketball players were recruited. This was a randomized, double-blinded, and counterbalanced crossover study with two experimental conditions: a-tDCS and Sham. The participants completed the basketball decision-making task and visuomotor skill after performing a 60-min sport-based videogame task with anodal (i.e., a-tDCS) or placebo (Sham) stimulation over the motion-sensitive middle temporal area. Worse response time was observed in visuomotor skill for Sham than a-tDCS postexperiment (p < .05). There was no main condition effect for accuracy of visuomotor skill (p > .05). There was more impairment in accuracy and response time in basketball decision-making skills for the Sham condition than a-tDCS (p < .05). Notably, a-tDCS over the motion-sensitive middle temporal area removed the negative effects of mental fatigue on perceptual-cognitive skills.

Does Social Media Use on Smartphones Influence Endurance, Power, and Swimming Performance in High-Level Swimmers?

Objective: This study aimed to investigate the repeated effect of social media on smartphones immediately before training sessions on inhibitory control (Stroop task), endurance (tethered swimming), countermovement jump (CMJ), and swimming performance (50, 100, and 400-m freestyle) in high-level female swimmers. Methods: It is a randomized and experimental investigation with parallel groups. Twenty-two participants underwent the eight weeks of the experiment. The swimmers (eight to twelve sessions per week with 15.9 ± 1.6 hours/week, and training experience of ~ 5.6 years) were randomized in two groups: control (CON, n = 11) and smartphone (SMA, n = 11). Immediately before each training session, the CON group watched videos about Olympic Games for 30-min. The SMA group used social network smartphone apps during 30-min. The inhibitory control, endurance, CMJ, and swimming performance were measured before and after the eight weeks of intervention. Results: No group x time interaction for 50-m freestyle (F(4, 18) = 1.04; p = .33; η2 = 0.09) and CMJ performance (F(4, 18) = 0.31; p = .58; η2 = 0.03) was found. Both experimental groups improved CMJ (F(2, 20) = 8.71; p = .01; η2 = 0.46). Only the CON group improved the 100-m (p = .02), 400-m freestyle (p = .01), and endurance performance (p = .01). The CON group improved the inhibitory control response (p = .01). Conclusion: It is concluded that the repeated effect of social media on smartphones immediately before swimming training sessions might reduce or nullify training gains on swimming and endurance performance.

Effects of smartphone use before resistance exercise on inhibitory control, heart rate variability, and countermovement jump.

BACKGROUND: The effect of MF induced by exposure time to social media smartphone apps on inhibitory control, heart rate variability (HRV), and high-intensity physical effort following a resistance exercise session might indicate whether strength and conditioning professionals should suggest avoiding smartphone usage before a resistance exercise session. AIM: The objective of this study was to analyze the effect of mental fatigue on inhibitory control, HRV, and countermovement jump (CMJ) in trained adults after resistance exercise. METHODS: A total of 16 trained males (21.4 ± 3.3 years) volunteered in this study. The participants performed resistance exercises with and without mental fatigue. The Stroop Task, countermovement jump, and heart rate variability were evaluated before and after the resistance exercise. The participants used smartphones in the mental fatigue condition, whereas the participants watched TV in the control condition. RESULTS: No condition × time interaction was found for the Stroop accuracy (p = 0.87), CMJ (p = 0.68), SDNN (p = 0.15), or pNN50 (p = 0.15) in the heart rate variability. An interaction was found for Stroop response time (p = 0.01) with a higher response time for the mental fatigue condition (p = 0.01). CONCLUSIONS: Mental fatigue impaired the inhibitory control performance after a resistance exercise session in trained adults.

Virtual reality promotes greater improvements than video-stimulation screen on perceptual-cognitive skills in young soccer athletes.

Background The literature has shown the positive effect of virtual reality (VR) in percepto-cognitive skills. However, the literature lacks findings about at what extent VR would be better than video. Purpose This study aimed to analyze the chronic effect of VR and video-stimulation screen training on passing decision-making, visual search behavior, and inhibitory control performance in young soccer athletes. Method A total of 26 young soccer players underwent an 8-week training protocol after being randomly assigned to the VR (n = 13) or video-screen (VID, n = 13) group. Passing decision-making, visual search behavior, and inhibitory control performance were measured before and after both interventions. Results A group x time interaction was found for decision-making performance (p < 0.01) and visual search behavior (p < 0.01). Both groups improved both decision-making performance (p < 0.01) and visual search behavior (p < 0.01); however, greater improvements were verified in VR (p < 0.01). Both VR and VID improved inhibitory control (p < 0.01), but no group interaction effect was observed (p > 0.05). Conclusion Our results suggest that VR leads to greater improvements in decision-making and visual search behavior in young soccer athletes than VID.

Effects of Mental Fatigue Induced by Social Media Use on Volleyball Decision-Making, Endurance, and Countermovement Jump Performance.

We studied the effects of repeated inducements of mental fatigue (MF) from using social media on smartphones immediately before training sessions by young male volleyball athletes, focusing specifically on their decision-making, endurance, and countermovement jump performance (CMJ). We pair-matched 24 participants according to their decision-making abilities and then, randomly assigned them to one of two 4-week block training groups: control (CON) and smartphone use (SMA). For a 30-minute period before each training session, the CON group watched TV and the SMA group used social media apps on smartphones. We found a significant group x time interaction effect for decision making (attack, p = 0.03; passing, p = 0.02) during training blocks. More specifically, only the CON group improved their decision making (attack, p = 0.03; passing, p = 0.02). Both groups significantly improved their CMJ performance (p = .01), with no significant group x time interaction effect for CMJ (p = 0.91). Neither group significantly improved their endurance (p = 0.56). We concluded that 30-minutes of repetitive social media app use on a smartphone immediately before 4-weeks of volleyball training sessions negatively affected decision-making in young male volleyball athletes.

Performing Repetitions to Failure in Lower-Limb Single-Joint Exercise Does Not Reduce Countermovement Jump Performance in Trained Male Adults.

Performing repetitions to failure (RF) is a strategy that might acutely reduce neuromuscular performance, as well as increase the rating of perceived exertion (RPE) and the internal training load (ITL) during and after a resistance training (RT) session. Thus, this study aimed to analyze the acute effects of RF or repetitions not to failure (RNF) on countermovement jump (CMJ) performance and the ITL in trained male adults. Eleven men performed two experimental protocols in randomized order (RF vs. RNF). Under the RF condition, participants performed three sets of the leg extension exercise using 100% of the 10RM load and rest intervals of 180-s between sets. Under the RNF condition, participants were submitted to six sets of five repetitions with the same intensity and an 80-s rest interval between sets in the same exercise. The CMJ test was analyzed before and following (15-s and 30-min, respectively) each experimental session. The ITL was evaluated by multiplying the RPE and the total session time, 30-min after the protocol. No main effect or interaction time vs. condition was found for CMJ performance (p > 0.05). In contrast, the ITL showed higher values under the RF condition (p = 0.003). Therefore, even though RF-induced a greater ITL, our results suggest that adopting this strategy in one single-joint exercise for the lower limbs does not seem sufficient to reduce CMJ height.

Effects of different training strategies with a weight vest on countermovement vertical jump and change-of-direction ability in male volleyball athletes.

BACKGROUND: Weight vest training (WVT) is a strategy used to improve the physical performance of athletes. The objective of this study was to determine the effects of different training strategies with weight vests on vertical jump and change-of-direction ability (CODA) in male volleyball athletes. METHODS: Fifteen volleyball athletes (22.87±3.04 years, 83.22±10.84 kg, 1.86±0.69 m) participated in a six-week training programme and were randomized into three groups: weight vest plyometric training (WPG), weight vest technical-tactical training (WTG) and a control group (CG). The additional weight of 7.5% of individual body mass was employed in the experimental groups. Before and after the WVT, athletes performed countermovement vertical jump (CMJ) and CODA (t-test) tests. RESULTS: Two-way ANOVA with repeated measures showed that CMJ height increased in all training groups (P<0.05), with the WTG inducing greater CMJ height gains in comparison to the CG (P<0.05). According to magnitude-based inference, the effects of the WTG strategy were "very likely" beneficial for the CMJ compared to the CG. In addition, t-test time decreased similarly among the three training groups (P<0.05). CONCLUSIONS: The results suggested that WVT may be incorporated in a volleyball training routine as an effective strategy for improving the CMJ performance in male volleyball athletes.

Smartphone Use Among High Level Swimmers Is Associated With Mental Fatigue and Slower 100- and 200- but Not 50-Meter Freestyle Racing.

Discovering any performance degradation effect of racing swimmers' use of social media smartphone apps might lead to new training and race preparation protocols, including pre-meet smartphone avoidance. This study's objective was to analyze the performance effects of using smartphone social media apps on the 50, 100, and 200-m freestyle among 25 high-level swimmers. Each participant performed the three race distances in two conditions: with smartphone app exposure (50-MF, 100-MF, and 200-MF) and without (50-CON, 100-CON, and 200-CON). We randomized the order of these two conditions across participants. While smartphone app use was not associated with statistically significant performance differences on the shortest race (50CON versus 50MF), a repeated measures ANOVA showed a significant condition × time interaction for the swimmers'100-m freestyle performance (p = 0.01), with a significantly slower performance following smartphone app use evident in the last half of this race (p = 0.02) but not in the first half (p = 0.41). We also found a condition × time interaction in the same direction (slower for swimmers who used the smartphone app) for the 200-m freestyle performance (p = 0.01), with the slower performance occurring in the second (p = 0.01) but not the first (p = 0.91), third (p = 0.07) or fourth (p = 0.06) quarters of this race. Thus, prolonged smartphone social media app use was associated with reduced performance from elite swimmers on the 100- and 200- but not the 50-m freestyle.

Different Foot Positioning During Calf Training to Induce Portion-Specific Gastrocnemius Muscle Hypertrophy.

Nunes, JP, Costa, BDV, Kassiano, W, Kunevaliki, G, Castro-e-Souza, P, Rodacki, ALF, Fortes, LS, and Cyrino, ES. Different foot positioning during calf training to induce portion-specific gastrocnemius muscle hypertrophy. J Strength Cond Res 34(8): 2347-2351, 2020-The aim of this study was to compare the changes in gastrocnemius muscle thickness (MT) between conditions such as which foot was pointed outward (FPO), foot was pointed inward (FPI), or foot was pointed forward (FPF). Twenty-two young men (23 ± 4 years) were selected and performed a whole-body resistance training program 3 times per week for 9 weeks, with differences in the exercise specific for calves. The calf-raise exercise was performed unilaterally, in a pin-loaded seated horizontal leg-press machine, in 3 sets of 20-25 repetitions for training weeks 1-3 and 4 sets for weeks 4-9. Each subject's leg was randomly assigned for 1 of the 3 groups according to the foot position: FPO, FPI, and FPF. Measurements with a B-mode ultrasound were performed to assess changes in MT of medial and lateral gastrocnemius heads. After the training period, there were observed increases in MT of both medial (FPO = 8.4%, FPI = 3.8%, and FPF = 5.8%) and lateral (FPO = 5.5%, FPI = 9.1%, and FPF = 6.4%) gastrocnemius heads, and significant differences for magnitude of the gains were observed between FPO and FPI conditions (p < 0.05). Positioning FPO potentiated the increases in MT of the medial gastrocnemius head, whereas FPI provided greater gains for the lateral gastrocnemius head. Our results suggest that head-specific muscle hypertrophy may be obtained selectively for gastrocnemius after 9 weeks of calf training in young male adults.

Acute effects of equated volume-load resistance training leading to muscular failure versus non-failure on neuromuscular performance.

BACKGROUND/OBJECTIVE: The aim of this study was to compare the acute effects of resistance training to failure (TF) and non-failure (TNF) with volume-load equalization on neuromuscular performance in recreationally resistance-trained adults. METHODS: Twenty-two trained men (age 21.4 ± 2.3 years) were included in a controlled, randomized, and design cross-over investigation with two experimental conditions and one-week of washout interval between them. The participants performed parallel back-squat adopting TF or TNF with volume, intensity, and rest between sets equalized. Countermovement jump (CMJ) height and peak power (PP) were used as mechanical indicators of neuromuscular performance. The mechanical variables were assessed in five moments (pre-experiment, post 15-s, 10-min, 20-min, and 30-min). RESULTS: When compared with the TNF condition, TF presented greater decrement on CMJ height (P < 0.001) and PP (P < 0.001) performance. The CMJ height and PP performance in parallel back-squat exercise following the TNF condition returned to the pre-experiment values 10-min after (P > 0.05). On the other hand, the TF condition promoted greater decrement in CMJ and PP performance compared with the pre-experiment and TNF protocol even 20-30 min later (P < 0.05). CONCLUSION: These findings suggest that TF promotes greater acute impairment on neuromuscular performance even when volume-load is equalized.

The effect of smartphones and playing video games on decision-making in soccer players: A crossover and randomised study.

The objective of this study was to analyse the effect of the use of social networks in smartphones or playing video games on the passing decision-making performance in professional soccer athletes. Participants were 25 male professional soccer athletes (mean ± SD: age 23.4 ± 2.8 years). The participants performed three randomised conditions divided into three groups: control (CON), smartphone (SMA), and video game (VID). Before and after each experimental condition, the Stroop Task assessed the level of induced mental fatigue. Then, the athletes performed a simulated soccer match. A CANON® camera recorded the matches for further analysis on passing decision-making performance. A group effect was identified (p < .01) with impairment on passing decision-making performance for the SMA (p = .01, ES = 0.5) and VID (p = .01, ES = 0.5) conditions. We concluded that the use of social networks on smartphones and/or playing video games right before official soccer matches might impair the passing decision-making performance in professional soccer athletes.

Dynamics of cognitive performance at rest and after exhaustive exercise in top-three world-ranked mixed martial arts athletes: a series of case studies.

Cognitive performance plays a key role in sports performance, especially in combat sports such as mixed martial arts (MMA). Studies with active and sedentary individuals showed either no change or decreased cognitive performance during or immediately after exercise. However, it is possible that elite MMA athletes would present preserved/improved cognitive performance after exhaustive exercise. In this series of cases studies, we tested this hypothesis by submitting three elite MMA athletes from the Bellator MMA® and UFC® to a cognitive assessment before, immediately after and 15 min after exhaustive exercise. A modified computerized version of the Stroop Test was used to test cognitive inhibition performance, from which reaction time (RT) and accuracy were obtained. The athletes performed an incremental exercise on a cycle simulator until volitional exhaustion. Immediately after exercise RT improved consistently in all three athletes (-6.5%; -8.0%; -15.0%), while accuracy presented a small increase (2.6%), decreases (-3.8%) or no change. Fifteen minutes after exercise, RT remained improved in two athletes (-9.1% and -15.5) or slightly increased (0.4%), while accuracy presented small increase in all athletes (0.5%; 1.3%; 2.1%) compared to pre-exercise. This result indicates that elite MMA athletes may present improved cognitive performance immediately after exhaustive exercise, which suggests that cognitive-motor training for MMA should be considered when planning a training program.

Aerobic Training Performed at Ventilatory Threshold Improves Psychological Outcomes in Adolescents With Obesity.

BACKGROUND: Physical activity may be as effective as some drugs for improving psychological outcomes; however, vigorous exercise may be needed for improving these outcomes in adolescents with obesity. The aim of this study is to examine the effects of low- and high-intensity training on self-esteem and symptoms of depression and anxiety in adolescents with obesity. METHODS: A total of 62 pubertal adolescents with obesity (age 15 [1.5] y, body mass index 34.87 [4.22] kg/m2) were randomized into high-intensity group (HIG, n = 31) or low-intensity group (LIG, n = 31) for 24 weeks. All participants also received nutritional, psychological, and clinical counseling. Body composition and measures of depressive symptoms, anxiety, and self-esteem were assessed at baseline and after 24 weeks. RESULTS: Depressive symptoms decreased significantly in both HIG (d = 1.16) and LIG (d = 0.45) (P ≤ .01). Trait anxiety decreased after 24 weeks for HIG (d = 0.81, P = .002) and LIG (d = 0.31, P = .002). No changes were observed in state anxiety or self-esteem. CONCLUSIONS: Results from the present study demonstrate that 24 weeks of multidisciplinary intervention improves depression and anxiety symptoms in adolescents with obesity; however, the magnitude of changes is higher in HIG compared with LIG.

Relative Age Effect is Modulated by Playing Position but is Not Related to Competitive Success in Elite Under-19 Handball Athletes.

This study aimed to verify the occurrence of the relative age effect (RAE) in male elite young handball athletes according to the playing position and its association with team performance in a World Championship. Data from 383 handball athletes from 24 countries who participated in the 7th World Men's Championship in the under-19 category were analyzed. RAE was investigated from the birth trimester of the athletes, their playing position, and final ranking in the Championship. The results showed an overrepresentation of athletes born in the first two trimesters (Q1 and Q2) (χ2(3) = 32.97; p < 0.001, ω = 0.29). The analysis of the athlete's position showed that most wings (χ2(3) = 18.37; p < 0.001, ω = 0.32) and backs (χ2(3) = 12.51; p = 0.006, ω = 0.34) were born in the first trimesters (Q1 and Q2). The ranking in the Championship presented no significant association with the date of the birth (p > 0.05). The results showed the existence of the RAE in youth handball elite athletes, especially for the back and wing positions. However, the strategy of selecting is questionable once the presence of RAE was not associated with competitive success.

Effect of duration of tapering on 100-m freestyle performance in swimmers / Efecto de la duración del tapering sobre el rendimiento en los 100 metros estilo libre en nadadores / Efeito da duração do polimento sobre o desempenho nos 100m livre em nadadores

Objective: The aim of this study was to analyze the effect of tapering duration on 100-m freestyle performance in swimmers. Method: This is an experimental research with 16 weeks' duration. Participants were 37 male swimmers aged between 15 and 17 years. The 100-m freestyle performance was evaluated before of the season start (pre-experiment), at the end of last week of each mesocycle (Preparatory, Specific I and Specific II) and the end of each week in the tapering phase. The performance was evaluated from the simulation of the 100-m freestyle race. Results: It was identified time effect for the 100-m freestyle performance (p < 0.001). Conclusion: It was concluded that two weeks of tapering were enough for the enhancement of 100-m freestyle performance

Objetivo: El objetivo de este estudio fue analizar el efecto de la duración del tapering sobre el rendimiento en los 100 metros estilo libre en nadadores. Método: Se trata de una investigación experimental con una duración de 16 semanas. Los participantes fueron seleccionados de forma no probabilística, totalizando 37 voluntarios del sexo masculino con edades entre 15 y 17 años. El rendimiento en los 100 metros estilo libre fue evaluado antes del inicio de la temporada, al final de la última semana de cada mesociclo (Preparatorio I, Específico I y Específico II) y al final de cada semana en la fase de tapering. El rendimiento de los jóvenes nadadores fue evaluado a partir de la simulación de la prueba de 100 metros estilo libre. Resultados: Fue identificado un efecto de tiempo (p < 0.001) para el rendimiento en los 100 metros estilo libre. Conclusión: Se concluye que dos semanas de tapering fueron suficientes para la potencialización del rendimiento en los 100 metros estilo libre

Objetivo: O objetivo deste estudo foi analisar o efeito da duração do polimento sobre o desempenho nos 100 m livre em nadadores. Método: Trata-se de uma investigação experimental com duração de 16 semanas. Os participantes foram selecionados de forma não probabilística, totalizando 37 voluntários do sexo masculino com idade entre 15 e 17 anos. O desempenho nos 100 m livre foi avaliado antes do início da temporada (pré-experimento), ao final da última semana de cada mesociclo (Preparatório I, Específico I e Específico II) e ao final de cada semana na fase do polimento. O desempenho dos jovens nadadores foi avaliado a partir da simulação da prova de 100 m livre. Resultados: Foi identificado efeito de tempo (p < 0.001) para o desempenho nos 100 m livre. Conclusão: Concluiu-se que duas semanas de polimento foram suficientes para a potencialização do desempenho nos 100 m livre em jovens atletas de natação

Frequency of resistance training does not affect inhibitory control or improve strength in well-trained young adults.

The objective of the current study was to compare the effects of resistance training frequency on cognitive inhibitory control in young adults with previous experience in the modality. Male participants (N = 36) were randomly placed into one of three experimental groups. Participants performed resistance training 1 (F1), 2 (F2), and 3 (F3) times per week for 24 weeks. The three groups performed exercises of equal intensity, volume-load, and rest duration. Cognitive inhibitory control (via Stroop test) was tested 72 h before (pre-experiment) and 72 h after (post-experiment) the resistance training program. No time vs. group interaction effects were noted for accuracy (F(4, 29) = 3.57, p = 0.18) or response time (F(4, 29) = 2.61, p = 0.06) on the Stroop test. These results indicate that increased resistance training frequency, when volume-load is kept constant, does not appear to potentiate cognitive inhibitory control.