Blood Flow Restriction training is a technique that restricts blood to a working area to mimic very high intensity exercise at lighter loads than normal. The restriction of venous return to the heart causes hydrogen, lactate, and other metabolic waste products to build up in the muscle. The muscle then conditions in this environment. Strength and hypertrophy can be improved from only using 20-30% 1 rep max load. Post operative and post injury patients can work on training with less strain on their joints.