Occlusion training or Blood Flow Restriction (BFR) uses elastic wraps, tourniquets or cuffs to reduce blood flow to the muscle group you are training. This type of training has been shown to have significant benefits to both strength and hypertrophy even at considerably lower loads than without BFR. Some studies have shown evidence of the same benefits with aerobic exercise such as walking.
Due to the fact that lower loads can be utilised during BFR training, it may be possible to apply the principles to individuals who are unable to complete exercises with high loads. In these populations it may be possible to gain the same benefit as heavily loaded exercises at low loads. Therefore, occlusion training can be beneficial to recently injured individuals who it is difficult to safely load. In preventing atrophy following injury or during immobilisation and inducing hypertrophy in non-weight-bearing patients at the beginning of the rehabilitation programmes, occlusion training could have its place.
However, occlusion training is rather uncomfortable. In injured populations, pain and exertion may be increased significantly during completion of the exercises and therefore may limit the ability to complete the training. Although, altering pressure of the restriction can alter pain and exertion levels. In addition, too high pressure may cause further injury to the muscle tissue due to the shear forces.
BFR can be used at every stage of rehabilitation, from immobilisation to strength and power training for returning to sport. During immobilisation, BFR has been shown to reduce the atrophy of muscles around immobilised joints, even without exercise. In rehabilitation, BFR with the same exercise protocol reduced the loss of muscle strength and was able to better maintain or increase muscle cross sectional area. The evidence for BFR benefits with aerobic training may also allow benefits with even gentle exercise. Studies have demonstrated increased VO2max, hypertrophy and strength with BFR over an aerobic training programme alone, although not in elite athletes. All of which allows maintenance of function greater than what is possible without BFR and its use should therefore be applied in acute injury and post-operative rehabilitation.
The protocols have been shown to elicit the same benefits for hypertrophy with loads as little as 20-30% of 1 repetition maximum, 1RM. Traditionally, without BFR, 65% of 1RM is required to produce the same hypertrophy benefits. The effect is greater for hypertrophy than strength training. Traditional strength training elicits greater improvements than BFR for strength. However, for injured individuals where the load required for strength benefits can not be applied, BFR has a role. In addition, in season use can allow for the maintenance and improvements in strength without causing the same muscle damage and delayed onset of muscle soreness, DOMS, commonly associated with high load strength training.
MUSCLE GROWTH = MUSCLE PROTEIN CREATED – MUSCLE PROTEIN DEGRADATION
Therefore, for a muscle to grow, the synthesis of new muscle protein must exceed the breakdown of muscle protein. Resistance training puts significant load through the muscle, stretching fibres, damaging the tissue and resulting in inflammation. This causes muscle protein degradation, breaking down muscle tissue and reducing the amount of muscle growth possible.
BFR reduces this inflammation due to the lighter load being utilised in this type of resistance training. Less stretching of sarcomeres results during training, subsequently reducing the protein breakdown and allowing greater muscle growth.
BFR decreases the oxygen supply to a muscle, encouraging recruitment of type 2 muscle fibres. This recruitment is only usually stimulated with high intensity training – high loads within resistance training. Lactate is produced due to oxygen restriction and this leads to greater GROWTH HORMONE release.
The process also positively influences production of Insulin-like growth factor, IGF-1, and MTOR, both hormones known to upregulate muscle protein synthesis. BFR also causes the downregulation of myostatin, the off switch of the body for protein synthesis.
INCREASED SYNTHESIS + DECREASES DAMAGE > GAINS!
It has been found that utilising occlusion training can cause adaptations in muscle hypertrophy in as little as two weeks as opposed to significantly longer durations required with traditional hypertrophy training!!
HOW IT’s DONE
The amount of blood flow restriction is dependent on the limb. For the arms, we are looking to restrict 50% of the arterial blood flow in to the arm, whereas with the legs we can restrict up to 80% of arterial blood flow.
Once the cuff is applied you will complete 4 sets of the exercises selected.
Set 1 – 30 reps
Rest – 30 seconds
Set 2 – 15 reps
Rest – 30 seconds
Set 3 – 15 reps
Rest – 30 seconds
Set 4 – 15 reps
Rest – 30 seconds
Each repetition follows a 2 second concentric and 2 second eccentric split. The full protocol for one exercise should last for 7 minutes. Please ensure cuff pressure is released immediately following the completion of the protocol!
Care should however be taken to maintain patient comfort levels, pain and exertion during completion of occluded exercises. The pressure of the cuff should also be adjust accordingly and duration of BFR should be carefully controlled. The amount of occluded blood flow can be measured using the cuff and stethoscope in a similar way to measuring blood pressure. Please do not try this type of training without sufficient understanding of risks involved or under supervision of a professional, it is at your own risk!