The effects of limb dominance and fatigue on running biomechanics

- Kinematic asymmetries during running are not affected by lower-limb dominance.
- Kinetic asymmetries during running are not affected by lower-limb dominance.
- Dominant and non-dominant lower limbs are not affected differently by fatigue.

PurposeTo establish whether lower extremity limb dominance has an effect on overground running mechanics.BackgroundIn attempts to resolve unilateral pathology, physical therapists often use the restoration of symmetry as a clinical milestone. While lower limb dominance has been shown to affect lower extremity mechanics during dynamic tasks such as jump landing, its effect on running gait is poorly understood. Further, despite the role of fatigue in running mechanics and injury, the interaction between fatigue and limb dominance has yet to be examined.MethodsThree-dimensional kinematic and kinetic data were collected on 20 females during overground running. Data were collected prior-to and following a treadmill run to exertion. Dominant and non-dominant limb data were compared in the fresh-state using a paired t-test. A 2-way repeated-measures ANOVA was used to test for an interaction between fatigue and limb dominance.ResultsThere were no significant differences between the kinematic or kinetic patterns of the dominant and non-dominant lower extremities during fresh-state overground running. Fatigue was not shown to interact with limb dominance.ConclusionLimb dominance did not affect kinematic or kinetic side-to-side differences. Therefore, physical therapists can continue to use resolution of lower extremity symmetry as a goal of therapy without having to account for limb dominance. The lack of an interaction between fatigue and limb dominance indicates that the dominant and non-dominant limbs fatigue at a similar rate.