The Eccentron from BTE harnesses eccentric resistance therapy, wherein muscles lengthen under force, for improved results. In geriatrics, the Eccentron provides 30%-40% more weight resistance than concentrics for improved strength, stability, and balance and a reduced risk of falling. In cardiopulmonary patients, it provides effective strengthening with 80% less oxygen than normally required. In athletes, it provides tighter muscle spring for enhanced explosive power and physical performance. In general rehabilitation, it increases comfort and allows for controlled dosing, single leg measuring therapy, and outcome tracking.