Date of Award


Degree Type


Degree Name

Master of Science (MS)


Kinesiology and Health Science

Committee Chair(s)

Brennan Thompson


Brennan Thompson


Talin Louder


Jon Carey


Previous research has found that lower limb muscle asymmetries increase with age and are linked to fall and injury risks. However, past studies lacked a wide variety of muscle function modes and measures as well as comparison to a comparable young aged group. The purpose of this study was to examine age-related lower limb muscle function asymmetries across a variety of muscle contraction types and velocities in young and old adults. Lower limb muscle balance, strength, power, and velocity were evaluated with concentric, isometric, isotonic, and eccentric muscle actions during a single-leg stance test and on single- and multi-joint dynamometers in 29 young (age = 21.45 ± 3.02) and 23 old (age = 77.00 ± 4.60) recreationally active men and women. Most (15 of 17) variables showed no statistical or functional (10% threshold) limb asymmetry (P > 0.05) for either age group. There was a significant main effect (P = 0.046; collapsed across groups) found for asymmetry (dominant > non-dominant) for the isotonic peak velocity variable. There was a significant (P = 0.010) group × limb interaction for single-joint concentric peak power produced at a slow (60 deg/s) velocity due to the non-dominant limb of the young group being 12.2% greater than the dominant limb (P < .001), whereas the old group was not asymmetrical (P = 0.965). The findings of this investigation indicate there is largely no age-related asymmetry of the lower limbs across a range of muscle function-related variables and modes, with a couple of notable exceptions. Also, the significant asymmetries for the isotonic peak velocity variable perhaps showed the sensitivity of this uncommonly used measure in detecting minimally present muscle function imbalances.