Improving Mobility and Function Following Transfemoral Amputation: A Novel Approach to Reverse Volumetric Muscle Loss

Inclusion Criteria:

* At least 18 years old
* History of lower limb unilateral transfemoral amputation.
* At least two years post lower limb amputation
* Able to ambulate independently without the use of aids (i.e., walking cane).
* Able to walk at least 10 minutes continuously without stopping.
* Has a safe residuum with no open wounds on either the residual or intact limb.
* Has a prosthetic limb with materials that are sound and safe to withstand the mobility requirements of the study.

Exclusion Criteria:

* Younger than 18 years old.
* Inability to give informed consent.
* Neurological disorder that affects gait.
* Participants with significant metal (greater than one orthopaedic screw) in either the residual limb or the sound/intact limb
* Participants who begin taking medications or change dosage of medications that could affect gait, balance, and cardiovascular function during the course of the study.
* Currently pregnant (or intend to become pregnant while participating in study).
* History of any condition where fatiguing contractions or resisted leg contractions are contraindicated.
* Blood clots in the leg, or any condition in which compression of the thigh or transient ischemia is contraindicated (e.g. open wounds in the leg).
* History of uncontrolled hypertension.
* History of heart failure.
* Head injury within the previous 6 months.
* Seizure disorder.
* History of vascular disease.
* History of thrombosis.
* History of sickle cell trait.
* History of genetic disease