Can restricting blood flow to athletes’ limbs while training boost performance? University of Toronto researchers investigate

Liam O'Brien, left, works with study participant to see if restricting blood flow to the arms can boost athlete performance - Can restricting blood flow to athletes' limbs while training boost performance? University of Toronto researchers investigate Ischemic preconditioning (IPC), a technique used to prepare an organ or tissue for a lack of blood or oxygen supply, was originally developed for use in clinical settings where there is an expected lack of blood and oxygen supply, for example during surgery or after an adverse event like a heart attack. But could it be used to enhance athletic performance? "IPC has been shown to have a protective effect on the body's tissues to subsequent ischemic episodes - events where there is inadequate blood supply and, therefore, oxygen supply to a tissue or organ - that would typically cause cellular damage," says Liam O'Brien, a first year PhD candidate at the University of Toronto Faculty of Kinesiology and Physical Education (KPE).  "So, when exercise researchers caught wind of it, they theorized it may be useful for enhancing exercise performance, seeing how our capacity to exercise is limited in part by the inability to deliver enough oxygen to the working muscles." The technique involves inflating blood pressure cuffs around one or multiple limbs at pressures that completely stop the flow of blood into or out of the limbs. The cuffs remain inflated for a brief period of about five minutes before being released for about five minutes, allowing for normal blood flow to resume through the limb.