title: Squat jump performance during growth in both sexes: comparison with cycling power.
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.
authors.affiliation: Laboratory of Exercise Biology of Physical Activity and Sport, Blaise Pascal University, Aubiere, France. Eric.Dore@univ-bpclermont.fr
authors.forename: Eric
authors.initials: E
authors.lastname: Doré
authors.forename: Mario
authors.initials: M
authors.lastname: Bedu
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Van Praagh
mesh_terms: D000293:Adolescent; D000704:Analysis of Variance; D000886:Anthropometry; D001823:Body Composition; D002648:Child; D002657:Child Development / Q000502:physiology*; D015444:Exercise / Q000502:physiology*; D005080:Exercise Test; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology; D018482:Muscle, Skeletal / Q000502:physiology; D012044:Regression Analysis; D055815:Young Adult