Blood Flow Restriction Therapy Speeds Up Injury Rehab

For an injured athlete, the rehabilitation process can seem slow and arduous. Time taken away from sport and training can be costly on many levels, reducing opportunities for advancement and reversing hard-earned performance gains. In the world of sports, innovative therapies that speed up healing and accelerate rehab time are in constant demand. One such innovation is blood flow restriction therapy, or BFRT.

While BFRT is a relatively new approach for injury rehab, the method has been used since the 1960s as a training tool, enabling athletes to build lean muscle mass without excessive weight loading. BFRT originated in Japan as KAATSU training in 1966. The idea is to apply pressure to an arm or leg during exercise to reduce venous blood flow from the limb while allowing normal arterial blood to flow into the muscle.

Prior to being used for injury rehab, BFRT was used by the military and by professional sports teams as a training aid. Years of research and multiple upgrades to the approach have expanded the popularity of BFRT, and gained the attention of the rehabilitation community.

The best way to visualize BFRT is to imagine an inflated blood pressure cuff applied to your upper arm or thigh prior to beginning an exercise set. As arterial blood flows into the muscles, venous blood is retained, causing the blood to pool. The pooling of blood brings on volitional fatigue at much lower training loads than conventional resistance exercise, eliciting an increase in strength and size at a much lower training volume.

Conventional resistance training loads are calculated at about 70% of one-repetition maximum (1RM), the total amount the individual can lift only once. A conventional protocol for muscle hypertrophy calls for volitional fatigue somewhere between 6 to 10 repetitions, repeated for 3 or more sets. With BFRT, loading is calculated at 20 to 30% of 1RM, with 15 to 30 repetitions per set, for 3 to 5 sets. Lower weights with higher reps and more sets is the accepted BFRT formula for optimal results.

Although the exact mechanisms for muscle adaptation are unclear, it is suspected that BFRT stimulates certain chemical reactions that normally occur with higher training loads, enhancing muscle strength and triggering muscle hypertrophy without heavy loading.

Because BFRT uses lower training loads than conventional resistance training, it reduces strain on injured joints, bones and soft tissues while enabling the patient to build strength and increase muscle mass during recovery. For example, a football player with a ruptured ACL can train the quadriceps muscles without overloading the knee joint, or a swimmer with a torn rotator cuff can train the biceps without overloading the shoulder.

Individuals who can benefit from BFRT include:

• Injured athletes who want to return to sport in the shortest possible time
• Elderly patients who need to increase muscle to promote balance and stability
• Patients recovering from surgery or injury
• Patients who are partially immobilized
• Patients with weakened muscles and muscle atrophy due to inactivity

As BFRT has grown in popularity, the procedures for its application have become more refined. A specialist trained in BFRT understands the nuances of the approach, and is able to get the best results.

Specific considerations for BFRT include:

• Cuff material and cuff width: The cuff itself measures and occludes blood pressure, so its width and materials are important for accuracy. While some clinics use simple elastic bands to occlude blood flow, they do not distribute pressure evenly, and are unable to measure it. Most researchers use a nylon cuff with a built in measuring device, similar to a regular blood pressure cuff, at widths ranging from 3 to 15 cm.
• Placement of the cuff: To achieve optimal blood occlusion, the BFRT cuff should be placed as high on the limb as possible, close to its proximal end. For example, when training the quadriceps, the leg cuff should be placed as close to the trunk as possible, just below the gluteal fold. For the upper arm, the cuff should be placed at the proximal end of the biceps, near the shoulder.
• Cuff pressure: Just as training load is measured as a percentage of 1RM, occlusion pressure is measured as a percentage of complete occlusion. Pressure should be measured with the patient seated in the position that the exercise will be performed. Research has shown 50% to be optimal occlusion pressure, with higher percentages offering no additional benefits in terms of results.
• Exercise protocol: A typical BFRT training protocol is 4 to 6 sets of 15 to 25 repetitions, at training loads of 20 to 30% 1RM. There is typically a 30 second rest taken between sets. While higher percentages of 1RM have been used in some research studies, remember that the main goal of BFRT is to achieve results at a much lower training load.
• Exercise selection: While most research on BFRT uses single-joint exercises such as a seated knee extension (knee joint only) or a biceps curl (elbow only), BFRT can be used for a variety of single or multiple joint exercises. Exercise selection is determined by the therapist, based on the needs of the individual patient.

In response to popular demand, specialized equipment and training have emerged to ensure the best results from BFRT. To get the most from a BFRT training session, find a specialist who has been trained to use the latest BFRT equipment, to get the best results. BFRT should be combined with other rehab methods to ensure a well-rounded and complete recovery protocol.