Jonathan D. Miller1, Matthew J. Hermes1, Mandy E. Parra1, Stephanie A. Sontag1, Trent J. Herdal & Andrew C. Fry1 1The University of Kansas, Lawrence, Kansas

The vertical jump is a commonly studied measure of athletic performance. Previously, relationships between basal testosterone and vertical jumps or other measures of explosive performance have been observed in highly trained athletes. However, the relationship between basal testosterone and vertical jump performance in untrained or recreationally active individuals is less clear. PURPOSE: The purpose of this study was to assess the relationship between basal testosterone levels and vertical jump performance in recreationally active males. METHODS: 10recreationally active males (mean±SD; age = 23.0±3.3yrs, height = 182.0±5.5cm, mass = 88.1±11.7kg) participated in this study. The experimental protocol involved anthropometric data and blood sample collection, a standardized warmup, and performing counter-movement jumps (CMJ) on a force plate sampling at 1000 Hz. Subjects were instructed to perform the CMJ with arms akimbo, descend to90º knee flexion, and jump maximally. Peak force (PF), peak power (PP), eccentric rate of force development (ERFD) and jump height (JH) were quantified from the CMJ. PF and PP were normalized by body weight in Newtons for analysis. Basal testosterone levels were determined from blood samples. Pearson product-moment correlations were used to analyze relationships between CMJ performance variables (PF, PP, ERFD, and JH) and basal testosterone(α=0.05). RESULTS: No significant relationships were observed between basal testosterone levels and the CMJ performance variables (r=-0.12 ‒ 0.06, p=0.737 –0.836), including JH (r=0.08, p=0.82). In addition, PF and ERFD were unrelated to JH(r=-0.04 ‒ -0.25, p=0.483‒ 0.912), but PP was predictive of JH(r=0.90, p<0.001), accounting for 81% of the variance. CONCLUSION: The training status and the homogeneity of the subjects likely play a role in the discrepancy in findings between the current study and previous studies which observed positive relationships between basal testosterone and vertical jump performance. Specifically, previous studies have used highly trained athletes, or more homogenous groups of subjects than the current study. Increased variability in confounding factors such as familiarity with maximal jumping and body adiposity likely obscure the relationship between basal testosterone and vertical jump height.

This document is currently not available here.