Older adults are the fastest growing age group in the US population . In spite of the well recognized benefits of maintaining an active lifestyle to delay the onset of functional impairment and disability, these older adults are the least physically active group compared to the others. The Center for Disease Control and Prevention and the American Heart Association recommend that older adults should spend at least 30 minutes a day, five days per week, doing moderate-intensity physical activity or 20 minutes of vigorous-intensity activity at least three days per week to maintain good...