An evolving protocol could make building muscle easier on your joints, or make it less painful to regain strength after an injury. Dr. Stuart McIntosh, a doctor of chiropractic and faculty member at Cleveland University-Kansas City (CUKC), along with colleagues, recently reviewed “blood flow restriction” (BFR) training for a presentation at the Association of Chiropractic Colleges Research Agenda Conference.
Most adults would benefit by maintaining strength as they age. Muscle weakness is highly prevalent in most clinical musculoskeletal conditions, and is commonly associated with both acute and chronic injuries that result in prolonged treatment or immobilization such as fractures, ligament, and other soft tissue injuries. Loss of muscle strength is a risk factor for development of osteoarthritis, which often leads to pain, and affects quality of life. Muscle weakness is commonly evident in non-injured older adults and is often associated with falls and other injuries. Increasing strength in adults is associated with lowered pain and improvements in physical functioning.
According to McIntosh, BFR training has generated interest in recent years among physicians and therapists that treat musculoskeletal injuries, because of the potential for individuals to build and rehabilitate muscle strength using a much lower weight resistance that is safer for joints. BFR training involves the use of a cuff or tourniquet system positioned around the proximal end of the extremity while performing a typical muscle building exercise. The cuff is inflated to a moderate pressure (typically ranging from 110 to 240 mm Hg) to maintain arterial flow while restricting venous return.
“Early studies regarding BFR training were published in 1998 but there has been much recent interest with a number of published articles within the last two to three years,” McIntosh said. “Theoretically, the occlusion of the venous system while performing resistance training promotes an anaerobic environment that promotes muscle building, similar to what is seen with high-intensity training while using lower weight resistance.”
Recently, a number of companies have entered the market selling BFR training equipment such as Kaatsu bands, Smart Tools, and other generic hook and loop resistance bands. Unlike some of the published studies in which pressure is measured, some users apply the bands to promote venous occlusion based upon perceived resistance.
Safety of this approach is a concern as the use of BFR training at this time should be supervised by a knowledgeable practitioner who is familiar with the participant’s health history. Possible contraindications may include cardiovascular disease, history of blood clots (hypercoagulability) and currently taking blood thinners.
McIntosh and his team reviewed over 20 recent published articles, finding that overall, BFR training is quite safe and well tolerated, and produces muscular strength gains similar to typical high-load training, but with much lower loads that are safer for joints and older adults. Specifically regarding older adults, BFR training is likely an effective intervention to stimulate strength gains, and can be used while walking (with resistance bands applied to the proximal thigh) to improve strength and improve lower extremity motor control with less strain applied to the knee and ankle joints with the typical strength training protocols.
McIntosh said that additional research is needed to explore effects in older adults, and to determine if falls are decreased using this intervention, as well as determining if knee and ankle pain are lessened when the supporting muscles are stronger. BFR training has the potential to be much easier on the joints, making this a positive intervention for older adults and patients who are rehabilitating after an injury or surgery.
