Program to improve mobility in aging (PRIMA) study: Methods and rationale of a task-oriented motor learning exercise program.

Walking difficulty is a common and costly problem in older adults. A potentially important yet unaddressed strategy to enhance walking ability through exercise intervention is to add a timing and coordination component in gait training (i.e. task specific timing and coordination exercise intervention) to the usual strength, endurance, and flexibility training. We describe the methods and rationale of a randomized single-blind, physical therapist supervised, exercise intervention trial to compare the effects of a standard strength, endurance, and flexibility program to a standard plus timing and coordination program in community-dwelling older adults walking slower than the desired gait speed of 1.2 m/s. Exercise sessions are twice weekly for 12 weeks. Participants are assessed at baseline, 12 weeks (post intervention), 24 weeks and 36 weeks. The primary outcome is gait speed, secondary outcomes represent components of the interventions (strength, endurance, flexibility, timing and coordination), and tertiary outcomes are measure of activity and participation (Late Life Function and Disability Instrument and physical activity). The findings of this trial will (1) establish if a standard-plus task specific timing and coordination program is superior to a standard strength and endurance program in improving mobility, activity and participation and (2) determine if the improvements are sustained over time. The information derived from this project will provide valuable insight into the prevention and management of walking difficulty, which is so common in older Americans.