Degree Name

PhD (Doctor of Philosophy)


Sport Physiology and Performance

Date of Award


Committee Chair or Co-Chairs

Michael H. Stone

Committee Members

Satoshi Mizuguchi, Kevin Carroll, William Hornsby


The prevalence of asymmetry in performance research has increased in recent years with mixed results. Much of the performance research has focused on unilateral jumping activities attempting to show relationships to other performance variables. However, bilateral ground reaction forces (bGRF) from jumps are more frequently assessed in athlete monitoring programs and the asymmetry from those jumps could be a simple addition to data already being collected. Research into bGRF asymmetries is lacking and no studies have addressed longitudinal changes. Additionally, research into the relationship of asymmetries to performance have infrequently used athletes. For these reasons, this dissertation will focus on bGRFs by assessing reliability, determining the relationship to performance, and tracking longitudinal changes among collegiate athletes. These data indicate that impulse has high absolute (ICC > 0.87) and relative (CV < 3.22) reliability values and should be the preferred metric for assessing jumping asymmetry. As well, a combination of the braking and propulsive phase above body mass has higher correlations (r = -0.25 to -0.49) to jumping performance compared to the propulsive phase alone (r = -0.09 to 0.26). Males and female soccer players have differing relationships with asymmetry as males had the greatest correlations between weighted countermovement jump (CMJ) asymmetry and weighted CMJ performance (r = -0.49), whereas females produced their greatest correlations with unweighted CMJs (r = -0.43). Additionally, all statistically significant correlations between asymmetry and performance were negative. Athletes with higher asymmetry values typically realize improvements over time without specific interventions, whereas athletes with lower values may not experience many fluctuations. Overall, asymmetry has negligible relationships to strength lev els (r = 0.30 to with strength training. 0.22) but seems to be associated with the improved motor coordination Indeed, athletes with higher asymmetry values involved even displayed trends of greater performance gains over time.

Document Type

Dissertation - unrestricted


Copyright by the authors.