Blood Flow Restriction Training in Pre-frail and Frail Older Adults

Frailty is most often defined as a syndrome of physiological decline in late life, characterized by marked vulnerability to adverse health outcomes. Intervention such as exercise, especially resistance exercise, has proven to be effective to improve frail condition in the elderly in the previous literature. However, blood flow restriction (BFR) training, a new resistance exercise training method, need merely lower resistance power and shorter training duration compared with traditional resistance exercise. Previous researches also demonstrated BFR can increase muscle mass and muscle strength in the healthy elderly but the effect of BFR training on the pre-frail or frail elderly is unknown. The aim of this study will test the effect of BFR training on muscle strength and functional performance in pre-frail or frail elderly. Participants aged over 60 years old with clinical frailty score between 3 to 5 will be recruited. Participants will be assigned to two groups using randomized block design with BFR training and control group. Structured questionnaire and physical function measurement will be used to assess the pre-intervention condition and outcome of different interventions. The participants will be assessed before training (pre-test), 3 weeks after training, and 6 weeks after training (post-test), and followed up at one and three months after training. Physical function measurement will include hand grip, muscle mass over trunk and extremity, muscle strength of lower extremity, gait speed and timed up and go test. Two-way repeated measures analysis of variance will be used to test the pre-test, 3-week, post-test and follow-ups difference between the two groups.