Blood Flow Restriction Therapy Impact on Musculoskeletal Strength and Mass

Abstract

Background: Blood flow restriction (BFR) training restricts arterial inflow and venous outflow from the extremity and can produce gains in muscle strength at low loads. Low-load training reduces joint stress and decreases cardiovascular risk when compared with high-load training, thus making BFR an excellent option for many patients requiring rehabilitation. Indications: Blood flow restriction has shown clinical benefit in a variety of patient populations including healthy patients as well as those with osteoarthritis, anterior cruciate ligament reconstruction, polymyositis/dermatomyositis, and Achilles tendon rupture. Technique Description: This video demonstrates BFR training in 3 clinical areas: upper extremity resistance training, lower extremity resistance training, and low-intensity cycling. All applications of BFR first require determination of total occlusion pressure. Upper extremity training requires inflating the tourniquet to 50% of total occlusion pressure, while lower extremity exercises use 80% of total occlusion pressure. Low-load resistance training exercises follow a specific repetition scheme: 30 reps followed by a 30-second rest and then 3 sets of 15 reps with 30-seconds rest between each. During cycle training, 80% total occlusion pressure is used as the patient cycles for 15 minutes without rest. Results: Augmenting low-load resistance training with BFR increases muscle strength when compared with low-load resistance alone. In addition, low-load BFR has demonstrated an increase in muscle mass greater than low-load training alone and equivalent to high-load training absent BFR. A systematic review determined the safety of low-load training with BFR is comparable to traditional high-intensity resistance training. The most common adverse effects include exercise intolerance, discomfort, and dull pain which are also frequent in patients undergoing traditional resistance training. Severe adverse effects including deep vein thrombosis, pulmonary embolism, and rhabdomyolysis are exceedingly rare, less than 0.006% according to a national survey. Patients undergoing BFR rehabilitation experience less perceived exertion and demonstrate decreased pain scores compared with high-load resistance training. Conclusion: Blood flow restriction training is an effective alternative to high-load resistance training for patients requiring musculoskeletal rehabilitation for multiple disease processes as well as in the perioperative setting. Blood flow restriction has been shown to be a safe training modality when managed by properly trained physical therapists and athletic trainers.