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In water polo, several high-intensity efforts are performed, leading to the fatigue process due to accumulation of hydrogen ions, and thus β-alanine supplementation could be an efficient strategy to increase the intramuscular acid buffer.

The aim of the current study was to investigate the effects of acute caffeine supplementation on anaerobic capacity determined by the alternative maximal accumulated oxygen deficit (MAOD_ALT) in running effort. Eighteen recreational male runners [29 ± 7years; total body mass 72.1 ± 5.8 kg; height 176.0 ± 5.4cm; maximal oxygen uptake (VO_2max) 55.8 ± 4.2 ml·kg^-1 ·min^-1] underwent a graded exercise test. Caffeine (6 mg·kg^-1) or a placebo were administered 1 hr before the supramaximal effort at 115% of the intensity associated with VO_2max in a double-blind, randomized cross-over study, for MAOD_ALT assessment. The time to exhaustion under caffeine condition (130.2 ± 24.5s) was 11.3% higher (p = .01) than placebo condition (118.8 ± 24.9 s) and the qualitative inference for substantial changes showed a very likely positive effect (93%). The net participation of the oxidative phosphorylation pathway was significantly higher in the caffeine condition (p = .02) and showed a likely positive effect (90%) of 15.3% with caffeine supplementation. The time constant of abrupt decay of excess postexercise oxygen consumption (τ₁) was significantly different between caffeine and placebo conditions (p = .03) and showed a likely negative effect (90%), decreasing -8.0% with caffeine supplementation. The oxygen equivalents estimated from the glycolytic and phosphagen metabolic pathways showed a possibly positive effect (68%) and possibly negative effect (78%) in the qualitative inference with caffeine ingestion, respectively. However, the MAOD_ALT did not differ under the caffeine or placebo conditions (p = .68). Therefore, we can conclude that acute caffeine ingestion does not modify the MAOD_ALT, reinforcing the robustness of this method. However, caffeine ingestion can alter the glycolytic and phosphagen metabolic pathway contributions to MAOD_ALT.

Postactivation potentiation (PAP) mechanisms and responses have a long scientific history. However, to this day there is still controversy regarding the mechanisms underlying enhanced performance after a conditioning activity. More recently, the term postactivation performance enhancement (PAPE) has been proposed with differing associated mechanisms and protocols than with PAP. However, these 2 terms (PAP and PAPE) may not adequately describe all specific potentiation responses and mechanisms and can also be complementary, in some cases. Purpose: This commentary presents and discusses the similarities and differences between PAP and PAPE and, subsequently, elaborates on a new taxonomy for better describing performance potentiation in sport settings. Conclusion: The elaborated taxonomy proposes the formula “Post-[CONDITIONING ACTIVITY] [VERIFICATION TEST] potentiation in [POPULATION].” This taxonomy would avoid erroneous identification of isolated physiological attributes and provide individualization and better applicability of conditioning protocols in sport settings.

Objectives: To investigate whether 4 wk of β-alanine supplementation improves total distance covered, distance covered and time spent in different speed zones, and sprint numbers during a simulated water polo game. Design: Double-blind, parallel, and placebo controlled. A total of 11 male water polo players participated in the study, divided randomly into 2 homogeneous groups (placebo and β-alanine). Methods: The participants performed a simulated water polo game before and after the supplementation period (4 wk). They received 4.8 g·d⁻¹ of dextrose or β-alanine on the first 10 d and 6.4 g·d⁻¹ on the final 18 d. Results: Only the β-alanine group presented a significant improvement in total sprint numbers compared with the presupplementation moment (PRE = 7.8 [5.2] arbitrary units [a.u.]; POST = 20.2 [7.8] a.u.; P = .002). Furthermore, β-alanine supplementation presented a likely beneficial effect in improving total distance covered (83%) and total time spent (81%) in speed zone 4 (ie, speed ≥ 1.8 m·s⁻¹). There was no significant interaction effect (group × time) for any variable. Conclusions: Four weeks of β-alanine supplementation slightly improved sprint numbers and had a likely beneficial effect on improving distance covered and time spent in speed zone 4 in a simulated water polo game.

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∙day^-1of 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.

Purpose: To test the reliability and validity of tethered swimming lactate minimum test in young swimmers. Methods: Lactate minimum test was performed twice to test the reliability (experiment 1; n = 13). In addition, the validity was investigated through lactate minimum test relationships with tethered swimming lactate threshold and peak force obtained during graded exercise test (experiment 2; n = 11). Finally, the correlations with mean speeds observed during 200-m (s200m) and 30-minute continuous efforts (s30min) were also analyzed (experiment 3; n = 15). In all experiments, the lactate minimum test began with 3-minute all-out effort to induce lactatemia, followed by an exhaustive graded exercise test. Results: The lactate minimum intensity and mean force during the entire 3-minute all-out effort (MF) showed high reliability (coefficient of variation < 8.9% and intraclass correlation coefficient > .93). The lactate minimum intensity was not different compared with lactate threshold (P = .22), presenting high correlations (r = .92) and agreement (95% limits of agreement = ±7.9 N). The mean force during the entire 3-minute all-out effort was similar to peak force obtained during graded exercise test (P = .41), presenting significant correlations (r = .88) and high indices of agreement (95% limits of agreement = ±11.3 N). In addition, lactate minimum test parameters correlated both with mean speeds observed during 200-m (r > .74) and 30-minute continuous efforts (r > .70). Conclusion: Thus, tethered swimming lactate minimum test can be used for training recommendations and to monitor aerobic adaptations in young swimmers.