ACUTE EFFECTS OF A WARM-UP INCLUDING ACTIVE, PASSIVE, AND DYNAMIC STRETCHING ON VERTICAL JUMP PERFORMANCE

Carvalho, FLP, Carvalho, MCGA, Simao, R, Gomes, TM, Costa, PB, Neto, LB, Carvalho, RLP, and Dantas, EHM. Acute effects of a warm-up including active, passive, and dynamic stretching on vertical jump performance. J Strength Cond Res 26(9): 2447-2452, 2012-The purpose of this study was to examine the acute effects of 3 different stretching methods combined with a warm-up protocol on vertical jump performance. Sixteen young tennis players (14.5 +/- 2.8 years; 175 +/- 5.6 cm; 64.0 +/- 11.1 kg) were randomly assigned to 4 different experimental conditions on 4 successive days. Each session consisted of a general and specific warm-up, with 5 minutes of running followed by 10 jumps, accompanied by one of the subsequent conditions: (a) Control Condition (CC)-5 minutes of passive rest; (b) Passive Stretching Condition (PSC)-5 minutes of passive static stretching; (c) Active Stretching Condition (ASC)-5 minutes of active static stretching; and (d) Dynamic Stretching Condition (DC)-5 minutes of dynamic stretching. After each intervention, the subjects performed 3 squat jumps (SJs) and 3 countermovement jumps (CMJs), which were measured electronically. For the SJ, 1-way repeated measures analysis of variance (CC x PSC x ASC x DC) revealed significant decreases for ASC (28.7 +/- 4.7 cm; p = 0.01) and PSC (28.7 +/- 4.3 cm; p = 0.02) conditions when compared with CC (29.9 +/- 5.0 cm). For CMJs, there were no significant decreases (p > 0.05) when all stretching conditions were compared with the CC. Significant increases in SJ performance were observed when comparing the DC (29.6 +/- 4.9 cm; p = 0.02) with PSC (28.7 +/- 4.3 cm). Significant increases in CMJ performance were observed when comparing the conditions ASC (34.0 +/- 6.0 cm; p = 0.04) and DC (33.7 +/- 5.5 cm; p = 0.03) with PSC (32.6 +/- 5.5 cm). A dynamic stretching intervention appears to be more suitable for use as part of a warm-up in young athletes.

Pre Vertical Jump Performance to Regulate the Training Volume

The purpose of this study was to assess the effect of training load regulation, using the CMJ at the beginning of the session, on the total plyometric training load and the vertical jump performance. 44 males were divided into 4 groups: No Regulation Group (nRG), Regulation Group (RG), Yoked Group (YG) and Control Group (CG). The nRG received 6 weeks of plyometric training, with no adjustment in training load. The RG underwent the same training; however, the training load was adjusted according to the CMJ performance at the beginning of each session. The adjustment made in RG was replicated for the volunteers from the corresponding quartile in the YG, with no consideration given to the YG participant's condition at the beginning of its session. At the end of the training, the CMJ and SJ performance of all of the participants was reassessed. The total training load was significantly lower (p=0.036; ES=0.82) in the RG and the YG (1905 +/- 37 jumps) compared to the nRG (1926 +/- 0 jumps). The enhancement in vertical jump performance was significant for the groups that underwent the training (p<0.001). Vertical jump performance, performed at the beginning of the session, as a tool to regulate the training load resulted in a decrease of the total training load, without decreasing the long-term effects on vertical jump performance.

Effects of strength and power training on neuromuscular adaptations and jumping movement pattern and performance

Effects of strength and power training on neuromuscular adaptations and jumping movement pattern and performance. J Strength Cond Res 26(12): 3335-3344, 2012-This study aimed at comparing the effects of strength and power training (ST and PT) regimens on neuromuscular adaptations and changes on vertical jump performance, kinetics, and kinematics parameters. Forty physically active men (178.2 +/- 7.0 cm; 75.1 +/- 8.6 kg; 23.6 +/- 3.5 years) with at least 2 years of ST experience were assigned to an ST (n = 14), a PT (n = 14), or a control group (C; n = 12). The training programs were performed during 8 weeks, 3 times per week. Dynamic and isometric maximum strength, cross-sectional area, and muscle activation were assessed before and after the experimental period. Squat jump (SJ) and countermovement jump (CMJ) performance, kinetics, and kinematics parameters were also assessed. Dynamic maximum strength increased similarly (p < 0.05) for the ST (22.8%) and PT (16.6%) groups. The maximum voluntary isometric contraction increased for the ST and PT groups (p < 0.05) in the posttraining assessments. There was a main time effect for muscle fiber cross-sectional area (p < 0.05), but there were no changes in muscle activation. The SJ height increased, after ST and PT, because of a faster concentric phase and a higher rate of force development (p < 0.05). The CMJ height increased only after PT (p < 0.05), but there were no significant changes in its kinetics and kinematics parameters. In conclusion, neuromuscular adaptations were similar between the training groups. The PT seemed more effective than the ST in increasing jumping performance, but neither the ST nor the PT was able to affect the SJ and the CMJ movement pattern (e.g., timing and sequencing of joint extension initiation).

Efeito agudo dos exercícios de flexibilidade no desempenho de força máxima e resistência de força de membros inferiores e superiores

This study investigated the acute effect of static stretching exercises (SSE) on maximum strength (MS) and strength endurance (SE) performance in lower and upper limbs. Thirteen volunteers participated in the study and were submitted to MS and SE (70% 1RM) tests in the bench press and squat exercises with or without SSE. The paired T test showed that the SSE decreased MS in the squat (141.2 +/- 34.2 vs 132 +/- 34.9kg, p=0.007) and in the BP (77.5 +/- 21.7 vs 71.7 +/- 17.7kg p=0.04). Squat SE was not affected by SSE (16.2 +/- 5.7 vs 16.3 +/- 6.8 repetitions p=0.48). On the other hand, bench press SE decreased significantly after SSE (11.7 +/- 4.8 vs 9.9 +/- 5.1 repetitions p=0.008). Therefore, SSE impaired MS performance on upper and lower limbs but SE was affected only on upper limbs. This difference in SE may be related to the stretching exercises volume applied to the size of each muscle group.

Relationship of aerobic and neuromuscular indexes with specific actions in judo

Objective. - The aim of this study was to verify the relationship of aerobic and neuromuscular indexes with specific situations in judo. Method. - Eighteen male judokas took part in the study. The following assessments were performed: vertical jump (CMJ) on a force platform; Special Judo Fitness Test (SJFT) to obtain the number of throws and percentage of the maximal heart rate (%HRmax) one minute after the test; match simulation to obtain the peak blood lactate (LACmax) and the percentage of the blood lactate removal (BLR); incremental test to obtain the velocity at the anaerobic threshold (vAT) and peak velocity (PV) reached in the test. Results. - A significant correlation was observed between the number of throws in the SJFT, the vAT (r = 0.60; P < 0.01), PV (r = 0.70; P < 0.01) and CMJ (r = 0.74; P < 0.01). A significant inverse correlation was found between the LACmax and vAT (r = -0.59; P = 0.01). Conclusions. - It can be concluded that the performance in the SJFT was determined by the aerobic capacity and power and the muscle power. Athletes with greater aerobic ability (vAT) presented lower blood lactate accumulation after the match. (c) 2011 Elsevier Masson SAS. All rights reserved.

Contribuição dos parâmetros biomecânicos para o desempenho de saltos verticais de jogadoras de basquetebol

O objetivo do presente estudo foi investigar a contribuição dos parâmetros biomecânicos para o desempenho do salto vertical com contramovimento (SV) e SV precedido de corrida (SVcorrida) em 19 jogadoras da seleção brasileira adulta de basquetebol feminino (26,2 ± 4,7 anos; 1,81 ± 0,07 m; 75,6 ± 12,6 kg; 20,4 ± 6,0% de gordura). Foram considerados os picos de força passiva (PFPa) e propulsão (PFP), tempo para alcance dos picos de força passiva (TPFPa) e propulsão (TPFP), "load rate" (LR), taxa de desenvolvimento de força (TDF), tempo de fase excêntrica (Texc) e concêntrica (Tcon). A análise de componentes principais revelou que 50,86% da altura de SV foi explicada por PFPa, TPFPa, LR, Texc e TPFP, e que 43,28% de SVcorrida foi explicada por PFPa, TPFPa, LR, PFP. Esses resultados sugerem que parâmetros temporais parecem contribuir de maneira mais significativa para o desempenho de salto, porém diferentes tipos de salto podem demandar comportamentos distintos de parâmetros biomecânicos.