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Irineu Loturco, Michael R. McGuigan, Valter P. Reis, Sileno Santos, Javier Yanci, Lucas A. Pereira, and Ciro Winckler

This study aimed to investigate the association between the optimum power load in the bench press (BP), shoulder press (SP), and prone bench pull (PBP) exercises and acceleration (ACC) and speed performances in 11 National Team wheelchair basketball (WB) players with similar levels of disability. All athletes were previously familiarized with the testing procedures that were performed on the same day during the competitive period of the season. First, athletes performed a wheelchair 20-m sprint assessment and, subsequently, a maximum power load test to determine the mean propulsive power (MPP) in the BP, SP, and PBP. A Pearson product–moment correlation was used to examine the relationships between sprint velocity (VEL), ACC, and the MPP in the three exercises. The significance level was set as p < .05. Large to very large significant associations were observed between VEL and ACC and the MPP in the BP, SP, and PBP exercises (r varying from .60 to .77; p < .05). The results reveal that WB players who produce more power in these three exercises are also able to accelerate faster and achieve higher speeds over short distances. Given the key importance of high and successive ACCs during wheelchair game-related maneuvers, it is recommended that coaches frequently assess the optimum power load in BP, SP, and PBP in WB players, even during their regular training sessions.

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Daniel Boullosa, César C.C. Abad, Valter P. Reis, Victor Fernandes, Claudio Castilho, Luis Candido, Alessandro M. Zagatto, Lucas A. Pereira, and Irineu Loturco

Purpose: To evaluate the effect of drop jumps (DJs) on performance time and pacing in a field test (ie, 1000 m) commonly used to evaluate endurance runners and to evaluate running and jumping performance in male and female athletes separately. Methods: Twenty elite endurance runners (male, n = 10, 27.8 [7.0] y, 62.3 [5.2] kg; female, n = 10, 25.9 [5.3] y, 51.7 [4.1] kg) competing in middle- and long-distance events participated in this study. After determination of the box height associated with the best reactive strength index, athletes randomly performed a warm-up with or without the inclusion of 5 DJs with the highest reactive strength index prior to a 1000-m track test. Performance time and pacing (250-m splits) were determined. Countermovement-jump heights at different time points and blood lactate concentration after running tests were also recorded. Results: A “possible” faster 1000-m time (162.4 vs 165.3 s) with a “very likely” faster first split (38.8 vs 40.3 s) was observed in male athletes in the DJ condition. In contrast, female athletes showed a “possible” slower running time (186.8 vs 184.8 s) and a “likely” greater blood lactate concentration after the 1000-m test in the DJ condition. Male and female athletes presented greater countermovement-jump performances after warm-up and running tests in both conditions. Conclusions: The inclusion of 5 DJs with the height associated with the best reactive strength index induced a “possible” improvement in 1000-m performance time in elite male endurance runners. The current protocol should be avoided in female athletes.

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Tomás T. Freitas, Lucas A. Pereira, Valter P. Reis, Victor Fernandes, Pedro E. Alcaraz, Paulo H.S.M. Azevedo, and Irineu Loturco

Purpose: To investigate the effects of a match-congested period on straight and curve sprint performance, change of direction (COD) speed and deficit, vertical jumping ability, and half-squat (HS) mean propulsive power (MPP) output in young soccer players. Methods: A total of 15 under-20 elite male soccer players participated in 14 matches over 8 weeks. The following assessments were performed before and after the congested fixture period: squat and countermovement jumps, 17-m linear sprint, curve sprint test for the “good” (CSGS) and “weak” (CSWS) sides, modified 17-m Zigzag test, and HS MPP. Magnitude-based inferences and a paired t test were used to analyze pre–post changes in the assessed variables. Results: Very likely (P < .05) decreases were noticed in 17-m sprint velocity (effect size [ES] [90% confidence limit; CL], −0.56 [−0.32 to −0.81]) and CSGS (ES [90% CL], −0.72 [−0.40 to 1.03]) after the 8-week period. A possible but nonsignificant impairment was revealed in CSWS (ES [90% CL], −0.18 [0.03 to −0.39]), and countermovement jump (ES [90% CL], −0.21 [−0.54 to 0.12]). Zigzag velocity (ES [90% CL], −2.90 [−2.45 to −3.36]) and COD deficit (ES [90% CL], 0.86 [0.52 to 1.20]) were almost certainly and significantly (P < .05) reduced and increased, respectively, after the match-congested period. An almost certain and significant (P < .05) reduction was found in HS MPP (ES [90% CL], −1.18 [−0.76 to −1.61]). Conclusions: Straight and curve sprint velocity, COD speed and deficit, and HS MPP were impaired after the match-congested period. Vertical jump height was possibly decreased. Seasonal phases comprising high volumes of soccer-specific training and competition seem to be detrimental to speed–power qualities in under-20 elite soccer players.

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Fernando Pareja-Blanco, Lucas A. Pereira, Valter P. Reis, Victor Fernandes, Ademir F.S. Arruda, Aristide Guerriero, Pedro E. Alcaraz, Tomás T. Freitas, and Irineu Loturco

Purpose: To examine the changes in resisted sprint performance and kinematics provoked by different sled loads in elite sprinters and rugby players. Methods: Eight elite male sprinters and 10 rugby union players performed 20-m sprints under 3 loading conditions (0%, 20%, and 60% body mass [BM]). Sprint time was measured in 0 to 5, 5 to 10, and 10 to 20 m, while stride length and hip, knee, and ankle angles were measured using an 8-sensor motion analysis system at the same distances. Results: Sprinters were significantly faster than rugby players in unresisted and resisted sprints using 20% BM (effect size, “ES” [90% confidence limit, CL] range: 0.65 [0.03 to 1.27]; 3.95 [3.10 to 4.81]), but these differences were not significant at 60% BM. Compared to rugby players, sprinters showed lower velocity decrement in resisted sprints using 20% BM (ES [90% CL] range: 0.75 [0.06 to 1.44]; 2.43 [0.83 to 4.02], but higher velocity decrement using 60% BM (ES [90% CL] range: 1.13 [0.43 to 1.82]; 1.46 [0.81 to 2.11]). No significant differences were detected in stride length between sprinters and rugby players for any sprint condition (ES [90% CL] range: 0.02 [−0.72 to 0.76]; 0.84 [0.13 to 1.54]). Rugby players showed higher hip flexion in resisted sprints (ES [90% CL] range: 0.30 [−0.54 to 1.14]; 1.17 [0.20 to 2.15]) and lower plantar flexion in both unresisted and resisted sprints (ES [90% CL] range: 0.78 [0.18 to 1.38]; 1.69 [1.00 to 2.38] than sprinters. Conclusions: The alterations induced by resisted sprints in sprint velocity and running technique differed between sprinters and rugby players. Some caution should be taken with general sled loads prescriptions, especially when relative loads are based on distinct percentages of BM, as training responses vary among sports and individuals.