Background The aim of the investigation was to compare the occurrence of post-activation performance enhancement (PAPE) after drop jumps, or heavy sled towing, and the subsequent effect on repeated sprint ability (RSA). Methods Ten young basketball players (17 ± 1 yrs) performed, in randomized order, RSA test with changes of direction after a standardized warm up followed by drop jumps, heavy sled towing, or no exercise (control condition). Neuromuscular assessments composed of two maximal voluntary contractions of the knee extensors, peripheral nerve stimulation, and surface electromyography (EMG), responses were recorded before and immediately after the RSA. The EMG signal of leg muscles during sprinting were also recorded as well as the blood lactate concentration. Results The drop jumps improved the RSA mean time (P = 0.033), total time (P = 0.031), and slowest time (P = 0.029) compared to control condition, while heavy sled towing did not change RSA outcomes (P > 0.05). All conditions exhibited a decrease of doublet high frequency stimulation force (pre-post measurement) (P = 0.023) and voluntary activation (P = 0.041), evidencing the occurrence from peripheral and central components of fatigue after RSA, respectively, but no difference was evident between-conditions. There was a significantly greater EMG activity during sprints for the biceps femoris after drop jumps, only when compared to control condition (P = 0.013). Conclusion Repeated drop jumps were effective to induce PAPE in the form of RSA, while heavy sled towing had no effect on RSA performance in young basketball players. Furthermore, both conditioning activities exhibited similar levels of fatigue following the RSA protocol. Thus, drop jumps may be used as an alternative to induce PAPE and thus improve performance during sprints in young male basketball players.

To verify the acute effect of drop jumps (DJ) on two repeated sprint ability tests (RSA), interspersed with a rest period simulating a basketball game break. Twelve first division basketball players (age: 24.8 ± 6.9 years; body mass: 97.0 ± 9.2 kg; height: 2.0 ± 0.1 m) performed, in a randomized crossover design, two RSA tests separated by 5 min after DJ or control conditions. The DJ condition comprised 5 DJs performed 4 min prior to the first RSA test, whereas 3 DJ were completed 30 s prior to a second RSA test. Surface electromyography was recorded from the lower body for root mean square (RMS) analyses during sprinting. Three countermovement jump (CMJ) tests were performed after warming up and immediately after the second RSA test. DJ improved RSA performance with a faster best time in the first RSA test (p = 0.035), and a shorter total time and mean time (p = 0.030) for the second RSA test. No significant differences were found in RMS between protocols. CMJdecreased in both conditions after the RSA tests (p < 0.05). This study revealed a post-DJ RSA potentiation in professional male basketball players. This simple and effective approach could be implemented at the end of the warm-up and before the end of game breaks to improve player preparedness to compete.

Purpose The purpose of the present study was to investigate the ergogenic effects of two doses of photobiomodulation therapy (PBMT) in comparison to placebo on markers of respiratory and muscle activity, blood acid–base, ion and lactate concentrations, indicators of muscle fatigue (global, central, and peripheral), and time to exhaustion in severe-intensity cycling. Methods Two separate studies were performed, both in a pseudorandomized and balanced, crossover design. In study 1, 14 male recreational cyclists completed three constant-load, severe-intensity cycling bouts that were duration matched. The PBMT (18 × 38 cm array with 200 diodes) treatments occurred before bouts at 260, 130, or 0 J (placebo) doses. EMG activity of selected lower limb musculature was assessed during each bout. Maximal voluntary contractions of knee extension with peripheral nerve stimulations and EMG activity evaluation of vastus lateralis was also performed before and after cycling. In study 2, 13 recreational cyclists performed three bouts of constant-load, severe-intensity cycling until exhaustion, preceded by PBMT as detailed previously. Blood lactate concentrations, respiratory responses, EMG activity, and capillary gasometry aspects were monitored. Results In both studies, there were no interactions effects (time–condition) on the EMG activity, which was displayed as root mean square (P ≥ 0.168) and median frequency (P ≥ 0.055) during cycling. In study 1, there were no interaction effects on the indicators of muscle fatigue after exercise (P ≥ 0.130). In study 2, there were no differences on time to exhaustion (P = 0.353) and no interaction effects among the physiological responses monitored (P ≥ 0.082). Conclusions Based on our findings, the PBMT at 260- and 130-J doses does not have a beneficial effect on muscle fatigue, cycling performance, metabolic parameters, and muscle activity in male recreational cyclists.

The purpose of this study was to investigate the effects of beta-alanine supplementation on specific tests for water polo. Fifteen young water polo players (16 ± 2 years) underwent a 200-m swimming performance, repeated-sprint ability test (RSA) with free throw (shooting), and 30-s maximal tethered eggbeater kicks. Participants were randomly allocated into two groups (placebo × beta-alanine) and supplemented with 6.4g∙dayof beta-alanine or a placebo for six weeks. The mean and total RSA times, the magnitude based inference analysis showed a likely beneficial effect for beta-alanine supplementation (both). The ball velocity measured in the throwing performance after each sprint in the RSA presented a very like beneficial inference in the beta-alanine group for mean (96.4%) and percentage decrement of ball velocity (92.5%, likely beneficial). Furthermore, the percentage change for mean ball velocity was different between groups (beta-alanine=+2.5% and placebo=-3.5%; p = .034). In the 30-s maximal tethered eggbeater kicks the placebo group presented decreased peak force, mean force, and fatigue index, while the beta-alanine group maintained performance in mean force (44.1%, possibly beneficial), only presenting decreases in peak force. The 200-m swimming performance showed a possibly beneficial effect (68.7%). Six weeks of beta-alanine supplementation was effective for improving ball velocity shooting in the RSA, maintaining performance in the 30-s test, and providing possibly beneficial effects in the 200-m swimming performance.

Brisola, GMP, Claus, GM, Dutra, YM, Malta, ES, de Poli, RAB, Esco, MR, and Zagatto, AM. Effects of seasonal training load on performance and illness symptoms in water polo. J Strength Cond Res 34(2): 406–413, 2020—The purpose of the study was to describe the training load distribution of a young female water polo team in different cycles of the season and verify its subsequent effects on specific fitness measured by the repeated sprints ability (RSA) test, aerobic endurance measured by the lactate minimum test, incidence and severity of upper respiratory tract infection (URTI) symptoms, and muscle damage markers. The training load (i.e., rating of perceived exertion × session duration) of 20 young female water polo players (mean ± SD: age = 15.65 ± 1.3 years; body mass = 60.93 ± 11.0 kg; height = 1.62 ± 0.1 m) was monitored, and the incidence and severity of URTI was assessed during part of the season. In addition, we assessed the lactate minimum speed (LMS), RSA, creatine kinase (CK), and lactate dehydrogenase (LDH) blood concentration during the season. The level of significance set was p < 0.05. The training loads were higher in the specific period (p < 0.01), whereas a high incidence of URTI was observed in the general cycle. The LMS was greater in the general cycle (p < 0.05), whereas total time and best time in the RSA test were greater in the competitive cycle (p < 0.05). The CK and LDH concentrations were significantly lower during the competitive cycle (p < 0.01). The general cycle of a female water polo team is critical regarding URTI and muscle damage, even with smaller training loads than the specific period.