Blood flow restriction for tendinopathy.

Centner and colleagues randomised 55 men to 14 weeks of calf training with BFR at 20 to 35 percent of maximum, heavy training at 70 to 85 percent, or no training. Achilles tendon stiffness rose 36.1 percent with BFR and 40.7 percent with heavy training; tendon size rose 7.8 and 4.6 percent. Calf muscle and strength rose in both groups. The differences between the training groups were not statistically detectable. These were healthy tendons, which the authors themselves flag.

Burton and McCormack found 13 studies: 3 in tendinopathy, 2 in tendon ruptures, and 8 in healthy tendons. They called the early evidence encouraging and stated that definitive conclusions and recommendations on BFR in tendon rehabilitation cannot be made at present. That is the state of the science, and this page does not claim more.

BFR belongs in the middle stage, when the tendon tolerates light loading but flares at the heavier loads that would drive adaptation. The exercise is the standard one for that tendon, calf raises for an Achilles, leg press or slow squats for a patellar tendon, with the cuff at the top of the limb. Response is judged by the tendon's own rule: no worse pain the next morning. The goal on the far side is heavy, slow loading, and the cuff comes out as it becomes possible.

Shockwave is a stimulus to a tendon that has stalled, aimed at restarting repair. BFR is a way to load the muscle and tendon when heavy loading is not tolerated. A plan can include both, with loading as the foundation, because no passive treatment builds a tendon's capacity to take force.