BLOOD FLOW restriction training is actually at its best away from the big-arms crowd (see sidebar), when used by those coming back from injury, as Johnny Owens, MPT and owner of the BFR company Owens Recovery Science learned in 2011. While at the Center for the Intrepid, a Department of Defense rehab facility in San Antonio, Owens started using BFR to help blast injury victims build muscle without traditional weights. All showed dramatic increases in power and strength.

“We called some researchers looking into it in academic labs,” says Owens, then CFI’s chief of human performance optimization. “One of them point-blank said, ‘I don’t know what has taken you guys in rehab so long to accept this concept.’”

Now, pro teams like the New Orleans Saints use BFR regularly to rehab injured players. No, you can’t lift heavy weights with a torn ACL, or a cast on your arm. But you can still pick up light dumbbells, and that’s all Beau Lowery, Saints director of sports medicine, needs to help you retain strength. “Because of the increase in growth hormone and other hormone levels, even if a guy is in a cast or immobilized, we are able create muscle hypertrophy,” he says.

The gain is not without pain, however. Done effectively, Lowery says the pressure that builds up during BFR often leaves Saints linemen in tears, and at the Andrews Institute, Opitz says employees opted out of early BFR studies simply because the process was too painful. So before you test-drive this cutting-edge training method, best seek the guidance of a pro.