What is Blood Flow Restriction?
Blood flow restriction, also known as occlusion training is a specialized physical therapy technique to strengthen and retain muscle function after an injury or surgery. It involves decreasing blood flow to a limb while performing a low-intensity exercise. Exercising the muscles in this low oxygen state allows you to use very light resistance and yet achieve strength gains that are similar to exercising under heavy loads or high intensity.
How does Blood Flow Restriction Work?
Blood flow restriction works by restricting the flow of blood to the arms or legs using pneumatic cuffs tied around the limbs. The cuff completely blocks the blood flowing away from the muscle through the veins and partially blocks blood flowing into the muscle through the arteries. The blockage of venous blood flow increases the concentration of lactate and metabolites in the muscle temporarily increasing muscle cell volume and causing muscle fibers to fatigue faster with low-intensity exercise due to lack of oxygen. These factors act as a stimulus for muscle hypertrophy. Blood flow restriction may also trigger the release of growth hormones that help with enhanced healing and growth of tissue.
Indications for Blood Flow Restriction
Indications for blood flow restriction include:
- Fractures in upper and lower extremities
- Muscle strains
- Ligament and tendon injuries
- General weakness
- Post-operative weakness
Contraindications for Blood Flow Restriction
Blood flow restriction may not be recommended for the following conditions:
- High blood pressure
- Poor circulation
- Renal Compromise
- Open wounds
Preparing for Blood Flow Restriction
Before undergoing blood flow restriction training, you should consult your doctor or physical therapist to ensure this form of therapy is right for you.
How is Blood Flow Restriction Performed?
A typical blood flow restriction training protocol may involve the following steps:
- The pneumatic cuff is placed around the muscle or limb to be strengthened.
- The pressure applied by the cuff is increased to about 1.5 times your resting systolic blood pressure or a pressure level determined by your condition.
- The muscle is exercised for about 5 minutes performing slow and deliberate movements that involve contracting and relaxing the muscle.
- You may feel a sensation of tightness in the muscle as it becomes engorged with blood during the exercise.
- The cuff is removed after performing the exercise to allow normal blood flow to return to the muscle.
Benefits of Blood Flow Restriction
Some of the possible benefits of blood flow restriction include:
- Prevent muscular atrophy
- Improve the bone mineral density
- Increase concentrations of growth hormone
- Improve muscle strength
Risks and Side Effects of Blood Flow Restriction
Some of the risks and side effects of blood flow restriction, especially when performed without proper medical guidance include:
- Muscle damage
- Blood clots
- Tingling sensation