Jump Squat is More Related to Sprinting and Jumping Abilities than Olympic Push Press.

The aim of this study was to test the relationships between jump squat (JS) and Olympic push press (OPP) power outputs and performance in sprint, squat jump (SJ), countermovement jump (CMJ) and change of direction (COD) speed tests in elite soccer players. 27 athletes performed a maximum power load test to determine their bar mean propulsive power (MPP) and bar mean propulsive velocity (MPV) in the JS and OPP exercises. Magnitude-based inference was used to compare the exercises. The MPV was almost certainly higher in the OPP than in the JS. The MPP relative to body mass (MPP REL) was possibly higher in the OPP. Only the JS MPP REL presented very large correlations with linear speed (r>0.7, for speed in 5, 10, 20 and 30 m) and vertical jumping abilities (r>0.8, for SJ and CMJ), and moderate correlation with COD speed (r=0.45). Although significant (except for COD), the associations between OPP outcomes and field-based measurements (speed, SJ and CMJ) were all moderate, ranging from 0.40 to 0.48. In a group composed of elite soccer players, the JS exercise is more associated with jumping and sprinting abilities than the OPP. Longitudinal studies are needed to confirm if these strong relationships imply superior training effects in favor of the JS exercise.

Effects of detraining on neuromuscular performance in a selected group of elite women pole-vaulters: a case study.

AIM: to determine the effects of 28 days of inactivity on neuromuscular performance of elite women pole-vaulters. METHODS: Four athletes undertook measurements of rate of force development (RFD), unloaded and loaded vertical jump tests, drop jumps and a 45 m sprint test before and after a transition period of planned inactivity. RESULTS: The RFD and the ability to accelerate over very short distances (5 m) while sprinting improved after training cessation. Acceleration over longer distances (5-45 m) was impaired, while unloaded and loaded vertical jump tests suffered trivial to small changes. CONCLUSIONS: Therefore, we conclude that detraining periods of approximately one month or even longer may be implemented in elite pole-vaulters without significantly impairing performance. In addition, given that some neuromechanical capacities are enhanced after training reduction, our results can help coaches to implement tapering strategies in order to induce neuromuscular improvements and/or to achieve peak performance.

Traditional Periodization versus Optimum Training Load Applied to Soccer Players: Effects on Neuromuscular Abilities.

It is unknown whether traditional periodization of strength-power training involving accumulation, transformation and realization blocks is superior to other simpler and more practical training schemes. The purpose of this study was thus to investigate changes in strength/power/speed characteristics of elite soccer players in response to either classic strength-power periodization (TSP) or optimum power load (OPL). 23 professional soccer players were randomly assigned to TSP or OPL for 6 weeks in-season regular training (3 times per week). TSP involved half squats or jump squats, depending on the respective training block, while OPL involved only jump squats at the optimum power load. Results revealed that both groups presented similar significant (P<0.05) improvements in squat one repetition maximum, squat and countermovement jump heights and change of direction speed. In addition, although both groups reported significant increases in sprinting speed (P<0.05); delta change scores demonstrated a superior effect of OPL to improve 10- and 20-m speed. Similarly, OPL presented greater delta change in mean propulsive power in the jump squat. Therefore, training continuously at the optimum power zone resulted in superior performance improvements compared to training under classic strength-power periodization.

Effects of far infrared rays emitting clothing on recovery after an intense plyometric exercise bout applied to elite soccer players: a randomized double-blind placebo-controlled trial.

The aim was to investigate the effects of far infrared (FIR) ray emitting clothes on indirect markers of exercise-induced muscle damage and physical performance recovery after a plyometric bout applied to soccer players. Twenty-one male players (18.9±0.6 years; 70.8±5.01 kg; 178.3±0.06 cm) performed 100 drop-jumps. Six hours after the bout, athletes put on FIR clothes (FIR) (density of 225 g·m(-2), 88% far infrared rays emitting polyamide 66 Emana yarn (PA66) fibre, 12% Spandex, emissivity of 0.88 and power emitted of 341 W/m2µm at 37°C in the 5-20 µm wavelength range, patent WO 2009/077834 A2) (N = 10) or placebo clothes (PLA) (N = 11). Mid-thigh circumferences, creatine kinase (CK), and delayed-onset muscle soreness (DOMS) were assessed before, immediately after and 24, 48, and 72 h after the bout. Squat (SJ) and countermovement jump (CMJ) heights were measured before and at 24, 48, and 72 h after, while 1RM leg press (maximum strength) was measured before and at 72 h after the plyometrics. No differences between groups were found in mid-thigh circumferences, SJ, CMJ or 1RM. CK increased significantly 24 h after the plyometrics in comparison to before (p < 0.05) in both groups. PLA showed significant DOMS increases at 24, 48, and 72 h, while FIR showed significant increases at 24 and 48 h (p < 0.05). DOMS effect sizes were greater in FIR (moderate at 48 h, ES = 0.737 and large at 72 h, ES = 0.844), suggesting that FIR clothes may reduce perceived DOMS after an intense plyometric session performed by soccer players.

Efeito do destreinamento na composição corporal e nas capacidades de salto vertical e velocidade de jovens jogadores da elite do futebol brasileiro / Efecto del desentrenamiento sobre la composición corporal, la capacidad de salto vertical y la velocidad de jóvenes futbolistas de élite / Effect of detraining on body composition, vertical jumping ability and sprint performance in young elite soccer players

Objetivo. Analisar os efeitos do destreinamento na composição corporal e nas capacidades de salto vertical e na velocidade. Método. Vinte e dois jogadores sub17 (16.4±0.4 anos; 70.0±7.1kg; 175.9±6.9cm) foram submetidos à avaliação antropométrica, de saltos verticais sem (SVSC) e com contramovimento (SVCC), e de velocidade linear, antes e após 2 semanas de destreinamento. Resultados. Houve aumento significante na gordura corporal (p<0.001) e, apesar da redução da velocidade não ser significante (p>0.05), houve 2.24% de aumento no tempo de 0‐5m (ES=0.78) e de 0.97% no tempo de 0‐20m (ES=0.41). Adicionalmente, houve tendência de aumento para o SVCC (p=0.056). Conclusão. Duas semanas de destreinamento provocaram alterações significantes na composição corporal e na capacidade da velocidade motora e na distância de 0‐5m em jovens futebolistas (AU)

Objective. To analyze the effects of detraining on body composition, vertical jumping and speed abilities. Methods. Twenty two under‐17 soccer players (16.4±0.4 years; 70.0±7.1kg; 175.9±6.9cm) were evaluated before and after two weeks of detraining. Anthropometric measurements, countermovement (CMJ) and squat jumps (SJ) and sprint speed tests were performed. Results. There was a significant increase in body fat (p<0.001) and despite the fact that the decrease in the speed was no significant (p>0.05), an increase of 2.24% in the 0‐5m time (ES=0.78) and 0.97% in the 0‐20m time (ES=0.41) were observed. In addition, there was an upward trend in the SJ (p=0.056). Conclusion. Two weeks of detraining resulted in significant alterations of the body composition and in speed performance (from 0 to 5m) in young elite soccer players (AU)

Objetivo. Analizar los efectos del desentrenamiento sobre el salto vertical, la velocidad de desplazamiento y la composición corporal en futbolistas jóvenes. Método. Veintidós jugadores (16.4±0.4 años, 70.0±7.1kg, 175.9±6.9cm) se sometieron a evaluaciones de composición corporal, saltos verticales y velocidad (carreras de 20 metros), antes y después de 2 semanas de desentrenamiento. Resultados. Se encontraron aumentos significativos en el porcentaje de grasa corporal (p<0.001) y a pesar de que la disminución de la velocidad no fue significativa (p>0.05), hubo una reducción del 2.24% (ES=0.78) y del 0.97% (ES=0.41) en los tiempos en 5 y 20m, respectivamente. Igualmente, se observó una tendencia al aumento del salto sin contramovimiento (p=0.056). Conclusión. Dos semanas de desentrenamiento produjeron alteraciones significativas en la composición corporal y en la velocidad (entre 0‐5m) de los jóvenes futbolistas (AU)

Jump Training in Youth Soccer Players: Effects of Haltere Type Handheld Loading.

The aim of this study was to compare the effects of a jump training program, with or without haltere type handheld loading, on maximal intensity exercise performance. Youth soccer players (12.1±2.2 y) were assigned to either a jump training group (JG, n=21), a jump training group plus haltere type handheld loading (LJG, n=21), or a control group following only soccer training (CG, n=21). Athletes were evaluated for maximal-intensity performance measures before and after 6 weeks of training, during an in-season training period. The CG achieved a significant change in maximal kicking velocity only (ES=0.11-0.20). Both jump training groups improved in right leg (ES=0.28-0.45) and left leg horizontal countermovement jump with arms (ES=0.32-0.47), horizontal countermovement jump with arms (ES=0.28-0.37), vertical countermovement jump with arms (ES=0.26), 20-cm drop jump reactive strength index (ES=0.20-0.37), and maximal kicking velocity (ES=0.27-0.34). Nevertheless, compared to the CG, only the LJG exhibited greater improvements in all performance tests. Therefore, haltere type handheld loading further enhances performance adaptations during jump training in youth soccer players.

A Correlational Analysis of Tethered Swimming, Swim Sprint Performance and Dry-land Power Assessments.

Swimmers are often tested on both dry-land and in swimming exercises. The aim of this study was to test the relationships between dry-land, tethered force-time curve parameters and swimming performances in distances up to 200 m. 10 young male high-level swimmers were assessed using the maximal isometric bench-press and quarter-squat, mean propulsive power in jump-squat, squat and countermovement jumps (dry-land assessments), peak force, average force, rate of force development (RFD) and impulse (tethered swimming) and swimming times. Pearson product-moment correlations were calculated among the variables. Peak force and average force were very largely correlated with the 50- and 100-m swimming performances (r=- 0.82 and -0.74, respectively). Average force was very-largely/largely correlated with the 50- and 100-m performances (r=- 0.85 and -0.67, respectively). RFD and impulse were very-largely correlated with the 50-m time (r=- 0.72 and -0.76, respectively). Tethered swimming parameters were largely correlated (r=0.65 to 0.72) with mean propulsive power in jump-squat, squat-jump and countermovement jumps. Finally, mean propulsive power in jump-squat was largely correlated (r=- 0.70) with 50-m performance. Due to the significant correlations between dry-land assessments and tethered/actual swimming, coaches are encouraged to implement strategies able to increase leg power in sprint swimmers.

Cardiac autonomic control in high level Brazilian power and endurance track-and-field athletes.

The autonomic nervous system (ANS) has an important role in physical performance. However, the cardiac ANS activity in high-level track and field athletes has been poorly explored. Thus, we tested the hypothesis that endurance and power athletes would present a markedly different cardiac autonomic control at rest. We analyzed the cardiac ANS by means of time and frequency domains heart rate variability (HRV) analyses and by symbolic analysis. Endurance athletes showed higher pulse interval than power athletes (1,265±126 vs. 1,031±98 ms respectively; p<0.05). No differences were found in time and frequency domains between the groups. However, the LF%, HF% and LF/HF ratio presented high effect sizes (1.46, 1.46 and 1.30, respectively). The symbolic analysis revealed that endurance athletes had higher 2V parasympathetic modulation (36±6.5) than power athletes (24±9.3; p<0.05). A reduced 0V sympathetic modulation was observed in endurance athletes (21±9.9) compared to power athletes (33±11; p<0.05 and ES=1.30). Our results suggest greater parasympathetic modulation and less sympathetic modulation in endurance athletes compared to power athletes. Additionally, the type of HRV analysis needs to be chosen with well-defined criteria and caution because their use in assessing cardiac autonomic modulation can interfere with the interpretation of results. In practical terms, symbolic analysis appears to better discriminate between cardiac autonomic activities of athletes with different training backgrounds than frequency domain analysis.