Leg Extension Strength, Explosive Strength, Muscle Activation, and Growth as Predictors of Vertical Jump Performance in Youth Athletes

2020 ◽  
Vol 2 (4) ◽  
pp. 336-348 ◽  
Author(s):  
Zachary M. Gillen ◽  
Marni E. Shoemaker ◽  
Brianna D. McKay ◽  
Nicholas A. Bohannon ◽  
Sydney M. Gibson ◽  
...  
2020 ◽  
Vol 12 (1) ◽  
pp. 91-100
Author(s):  
Jaime Della Corte ◽  
Wendell Luiz M. Pereira ◽  
Eduardo Emil Lacerda S. Corrêa ◽  
João Gabriel Miranda de Oliveira ◽  
Bruno Lucas Pinheiro Lima ◽  
...  

SummaryStudy aim: To evaluate the effect of power and muscle strength training on skin temperature and the performance of the vertical jump with countermovement (CMJ).Material and methods: The sample consisted of four male basketball athletes of the under-17 category (age: 15.75 ± 1.0 years). 48 hours after anthropometric evaluation and determination of the loads for 1 repetition maximum (1RM) in the leg extension exercise, the athletes were subjected, through crossover-type entrance, to power (PTP) and strength (STP) training protocols. The protocols consisted of three sets with loads of 60% and 90% of 1RM for PTP and STP, respectively. Thermographic images of the thighs were taken before and immediately after each training session.Results: There were significant differences in results between the two training protocols, with increased total repetitions (t = 13.481; p < 0.05) and total training volume (t = 15.944; p < 0.05) in the PTP, and increase in the % of 1RM (t = 33.903; p < 0.05) and rating of perceived exertion (t = 6.755; p < 0.05) in the STP. The skin temperature before and after PTP and STP showed no significant differences. In the post-STP, the CMJ presented significant reductions in height (t = 3.318; p < 0.05), flight time (t = 3.620; p < 0.05), velocity (t = 3.502; p < 0.05), and force (t = 4.381; p < 0.05). There were no significant differences in pre-and post-STP CMJ.Conclusions: Power and maximum strength training in the leg extension exercise performed until concentric failure appears to be a method that induces thermal stress on the skin. This training directly influenced the performance of the vertical jump after the stimulus.


2019 ◽  
Vol 35 (5) ◽  
pp. 327-335 ◽  
Author(s):  
Zachary M. Gillen ◽  
Lacey E. Jahn ◽  
Marni E. Shoemaker ◽  
Brianna D. McKay ◽  
Alegra I. Mendez ◽  
...  

This study measured peak force (PF), peak rate of force development (PRFD), peak power (PP), concentric impulse, and eccentric impulse during static jump (SJ), countermovement jump (CMJ), and drop jump (DJ) in youth athletes to examine changes in vertical jump power with progressively greater eccentric preloading in relation to age, maturity, and muscle mass. Twenty-one males ranging from 6 to 16 years old performed the following vertical jumps in a random order: SJ, CMJ, and DJ from drop heights of 20, 30, and 40 cm (DJ20, DJ30, and DJ40, respectively). Measurements included PF, PRFD, PP, eccentric impulse, and concentric impulse for each vertical jump condition. Maturity offset was calculated, while ultrasound images quantified thigh muscle cross-sectional area (CSA). PF and PRFD increased from CMJ to DJ20. PP increased from SJ to CMJ. Concentric impulse remained unchanged, but eccentric impulse increased systematically from across jumps. The change in PP from SJ to CMJ was correlated with age, height, weight, maturity offset, and CSA. The CMJ resulted in the greatest concentric PP with the least amount of eccentric preloading. The inability of young athletes to translate the energy absorbed during the eccentric phase of the stretch-shortening cycle of DJs may be influenced by growth and development.


2021 ◽  
Vol 9 (7_suppl3) ◽  
pp. 2325967121S0017
Author(s):  
Sophia M. Ulman ◽  
Laura Saleem ◽  
Kirsten Tulchin-Francis

Background: The Functional Movement Screen (FMS) is a tool designed to establish a baseline for fundamental movement capacity, highlight limitations and limb asymmetries, and identify potential injury risk. Previous research has shown that individual components of the screen are also indicative of injury risk, as well as potential predictors of athletic performance unlike the FMS composite scores. However, this literature is limited and lacks statistical power. Identifying which component scores are predictive of injury risk and athletic performance would provide a quick, powerful tool for coaches and trainers to evaluate athletes. Purpose: To determine if individual component scores of the FMS are associated with athletic performance in highly-active youth athletes. Methods: Youth athletes participated in the Specialized Athlete Functional Evaluation (SAFE) Program. Data collection was extensive, however, for the purpose of this abstract, only a selection of data was analyzed – age, BMI, years played, total number of past injuries, isokinetic knee strength, 10- and 20-meter sprint, single-leg hop (SLH) distance, and FMS scores. Seated knee flexion/extension strength was collected at 120°/second using a Biodex System 4, and peak torque was normalized by body weight. The maximum distance of three SLHs was recorded for each leg and normalized to leg length. FMS scores used for analysis included the total composite and component scores, including the deep squat, hurdle step, in-line lunge, shoulder mobility, active straight-leg raise, trunk stability push-up, and rotary stability. Wilcoxon Signed Ranks Tests were used to determine side-to-side differences, and Kruskal-Wallis tests were performed to determine differences in athletic performance based on FMS scores ( α<0.05). Results: A total of 38 highly-active, youth athletes (26F; 15.4±2.6 years; BMI 21.0±5.3) were tested. Participants reported playing organized sports for 8.7±3.4 years, having 2.0±1.2 past sports-related injuries, and 74% reported specializing in a single sport. No side-to-side differences were found. While the composite FMS score significantly differed by number of past injuries ( p=0.036), it was not associated with athletic performance. Alternatively, left knee strength, sprint speeds, and right hop distance significantly differed by the hurdle step component score (Table 1). Conclusion: While the composite FMS score was not an indicator of athletic performance, the hurdle step component score was associated with strength, speed, and jump performance. This individual task could be a beneficial tool for coaches and trainers when evaluating athletic ability and injury risk of athletes. Tables/Figures: [Table: see text]


2017 ◽  
Vol 49 (5S) ◽  
pp. 127
Author(s):  
Nick Diaz ◽  
Courtney Jensen ◽  
J. Mark VanNess

2014 ◽  
Vol 20 (0) ◽  
pp. 48 ◽  
Author(s):  
Teet Meerits ◽  
Sebastian Bacchieri ◽  
Mati Pääsuke ◽  
Jaan Ereline ◽  
Antonio Cicchella ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document