Squat Jump Performance During Growth in Both Sexes

Abstract

The purpose of this cross-sectional study was to investigate leg muscle power and compare two activities (jumping and cycling) in 383 girls and 407 boys ages 9-19 years. Results in anthropometric characteristics and jumping performance were comparable until midadolescence, and sex differences were observed. Lean leg volume (LLV) was the reason for most of the variance (76% in girls and 88% in boys) in jumping performance. However the LLV exponent was higher than expected in boys but not girls. Therefore, unidentified qualitative changes of muscle function during growth in boys must be considered. The squat jump index (SJI) was highly correlated to cycling peak power (CPP; N = 790, r = .94, p < .001). Although prediction error of CPP from SJI was less than 5% when considering each sex-and-age group, individual errors mounted to 40%. Due to its practicability, SJI is recommended in large-scale developmental prospective studies. However, cycling and jumping protocols are not interchangeable when measuring peak power values.

Explosive Strength Modeling in Children: Trends According to Growth and Prediction Equation

“…Although our study did not investigate coordination, D'Hondt et al [31] found an inverse correlation between motor coordination and lower mass in children of 5-10 years, and Stodden et al [35] reported that children with a higher level of motor coordination exhibit greater performance (explosive strength). In this sense, sex differences in lower limb power performance have been related to the expression of significant differences in fat-free mass [36]. Subsequently, changes in force production at the age of 13-14 years have been attributed to the dramatic increase in steroid concentrations in males [37].…”

The Measurement of Maximal (Anaerobic) Power Output on a Cycle Ergometer: A Critical Review

“…Significant correlations have been found between maximal power on a cycle ergometre and vertical jump performances [105, 190–194] and the stair case test of Margaria [191]. P max⁡ expressed per kilogram of body mass is significantly correlated with a squat jump (SJ) [192, 194] and a countermovement jump (CMJ) [105, 193].…”

“…P max⁡ expressed per kilogram of body mass is significantly correlated with a squat jump (SJ) [192, 194] and a countermovement jump (CMJ) [105, 193]. However, the prediction of CMJ [105] or SJ [194] from P max⁡ is not accurate in spite of high correlation coefficients ( r = 0.87) [105, 192].…”

“…P max⁡ expressed per kilogram of body mass is significantly correlated with a squat jump (SJ) [192, 194] and a countermovement jump (CMJ) [105, 193]. However, the prediction of CMJ [105] or SJ [194] from P max⁡ is not accurate in spite of high correlation coefficients ( r = 0.87) [105, 192]. For example, individual errors were close to 40%, and the authors concluded that squat jump is recommended in large-scale developmental prospective studies but that cycling and jumping protocols are not interchangeable when measuring peak power [194].…”

“…However, the prediction of CMJ [105] or SJ [194] from P max⁡ is not accurate in spite of high correlation coefficients ( r = 0.87) [105, 192]. For example, individual errors were close to 40%, and the authors concluded that squat jump is recommended in large-scale developmental prospective studies but that cycling and jumping protocols are not interchangeable when measuring peak power [194]. In karate competitors, P max⁡ in cycling was not significantly correlated ( r < 0.42) with performances in squat jump and countermovement jump [195].…”