Peace of Mind: Autoregulation Blood Flow Restriction

In today’s competitive environment, athletes are under increased pressure to perform well and avoid getting hurt. Blood flow restriction (BFR) is a new and improved training strategy resulting from the desire to maximize rehabilitation and performance outcomes. Athletes and practitioners can use a tourniquet cuff for purposes more than assisting with blood pressure measurements. Today, practitioners employ BFR technique to create a hypoxic condition in injured muscles to speed healing and strengthen the affected area. Blood flow restriction significantly improves muscle strength, endurance, and hypertrophy, which can be useful in managing injuries and training healthy athletes⁽¹⁾. However, there is still doubt about its optimal use in clinical practice as many factors influence the successful implementation, namely differences in equipment and methodologies⁽¹⁾.

To provide the same benefits as high-load exercise, blood flow restriction entails occlusion close to the target muscle or area, partially decreasing arterial blood flow, and occluding venous return⁽²⁾. Training with BFR is conducted at low intensities (around 20-40% of max exertion) or low/medium intensities during aerobic exercises when targeting the cardiopulmonary capacities⁽³⁾.

“Blood flow restriction therapy has shown promise in improving muscle strengthening and recovery.”

Furthermore, recent research on blood flow restriction has revealed additional insights into its potential benefits and applications. Researchers at the University of Tokyo investigated the effects of blood flow restriction on muscle protein synthesis (MPS) in older adults. They found that low-intensity resistance exercise combined with blood flow restriction significantly increased MPS in older individuals compared to exercise without restriction⁽⁴⁾. These findings suggest that BFR may be particularly beneficial for older adults, who often face challenges maintaining muscle mass and strength.

Another area of interest is the potential role of blood flow restriction in accelerating post-injury recovery. In a study published in the Journal of Athletic Training, researchers examined the effects of blood flow restriction therapy on muscle recovery following anterior cruciate ligament (ACL) reconstruction surgery⁽⁵⁾. The study demonstrated that BFR combined with traditional rehabilitation exercises resulted in greater quadriceps muscle size and strength than standard rehabilitation alone. Therefore, blood flow restriction may offer a valuable adjunctive treatment for athletes recovering from ACL injuries, allowing for a faster and more complete return to sport. These benefits, along with the low-load nature of BFR training, place less strain on the graft, cartilage, and meniscal and bone bruising injuries associated with the original injury⁽⁵⁾.

The newest advancement is the inclusion of autoregulation training into BFR protocols. Throughout the inflation cycle, autoregulation keeps the pressure in the cuff constant. When employing a non-autoregulated cuff, the muscle contracts and applies pressure to the cuff, which can result in a pressure spike, discomfort, a change in hemodynamics, and the release of air, which can then result in a reduction in the cuff pressure (see figure 1)⁽⁶⁾. Thus, making autoregulated cuffs potentially safer and more effective.