Date of Award


Document Type

Scholarly Project

Degree Name

Doctor of Physical Therapy (DPT)


Physical Therapy

First Advisor

Mark Romanick


Aging -- physiology; Mice -- anatomy & histology; Muscle Weakness; Sarcopenia


This research project focused on the differences observed in muscle fiber composition and surface area between wild type mice and Ames dwarf mice as they aged. A mouse model was utilized because the skeletal muscle framework of mice closely resembles that of human muscle; thus, the observations seen within the mice may also be seen within humans as they age. Comparisons between the wild type and dwarf mice include a smaller cross-sectional muscle area in a dwarf mouse and no drastic change in the percentages of fast and slow twitch muscle fibers as the dwarf mouse ages. Furthermore, differences in fiber length and cross-sectional muscle area between wild type and dwarf mice were revealed. However, exact conclusions on muscle fiber composition and surface area as mice age cannot be drawn secondary to the limited number of lower extremity musculature that was obtained. Current knowledge of sarcopenia and its effects were also explored throughout this paper.