| Frequent readers may remember I joined the torn ACL club a few months ago. Anyone who has experienced the dreaded knee pop knows surgery is just the beginning of the recovery process. Months of physical therapy start soon after ligament reconstruction to rebuild muscles and your range of motion. What caught me by surprise was how quickly I lost my quad muscles after surgery. Called atrophying, it’s a common occurrence after an operation that leads to rapid loss of muscle due to underuse. Enter blood flow restriction therapy, or BFR. Adding weights and resistance exercises can help rebuild muscle over time, but my physical therapist introduced me to this device to kick start the process. BFR training can be used on any limb, including the arms, to help strengthen muscles. A band on my thigh functions similar to a blood pressure monitor, but this one cuts the blood flow to my leg by 80%. My leg slowly turns purple. A similar feeling to a limb falling asleep kicks in. And then I perform a series of exercises. By restricting blood flow, the band “tricks” muscle into thinking it’s working harder than it actually is, allowing it to get stronger, quicker. The method has been around since the 1980s when the cuffs were used on wounded soldiers, Drew Contreras, a physical therapist and vice president of strategic affairs at the American Physical Therapy Association, told me. But it’s a method that’s grown in popularity in the past two decades and has become standard practice for a wide range of patients. If you keep up with the latest fitness trends, you may be familiar with these devices. They’ve even popped up at the Olympics. But it's still pricey for many to buy their own, with some retailing as high as $500 for a set. And they can be expensive for clinics, too, which may determine how widely available the therapy is. After a ligament reconstruction, like an ACL surgery, you don’t want to place too much weight or strain on the recovering area, Contreras said. But you do want the muscles around the surgery site to get stronger. The cuff simulates a tourniquet and relieves stress on joints that exercises with heavy weights may cause. A 2022 study said there is growing evidence BFR training can help improve cardiovascular fitness too. Contreras said therapists have seen success using the device on older patients to help strengthen muscles. It’s also a good strategy for athletes looking to maintain weight training during the off season. Contreras said to be wary of machines that could be a true tourniquet – those will cut all blood flow to your limb and possibly damage your tissue. Make sure the device you buy is just restricting blood flow instead. Otherwise, it’s best to be supervised by a professional. A few hours after using BFR at physical therapy, my leg feels like it just ran a few miles. “You have to give yourself enough recovery time because it is exhausting,” Contreras said. – Jessica Nix | 
