Fellowship in support of Kristen Jakubowski: Quantifying the contribution of age-dependent musculotendon changes to ankle impedance in older adults

Impaired mobility is the leading cause of disability among older adults. An essential component of mobility is adapting to unexpected perturbations. Older adults, however, have a reduced capacity to respond to such perturbations which increases their risk of falling. To maintain balance in response to a perturbation, one must rapidly and appropriately generate a corrective torque. The ankle produces a substantial portion of this corrective torque, which arises from ankle impedance and changes in muscle activation. However, it is currently unknown how aging impacts ankle impedance. Ankle impedance is likely altered by the wellestablished age-dependent changes within the muscle and tendon. This study will use an innovative measurement technique to simultaneously quantify the impedance of the ankle, muscle, and tendon, allowing for insight into how musculotendon changes impact ankle impedance. This work is the first step in determining an underlying mechanism impairing older adults’ mobility.