How to practically apply blood flow restriction:
As described in the first of the two blogs, blood flow restriction (BFR) training is done by placing a tourniquet on a limb. The cuff needs to be tightened to a specific pressure that prevents blood from flowing back to the body but allows some (but not all) of the normal amount of blood to flow towards the leg. For example, when using BFR after a knee surgery, the cuff would be placed around the upper thigh. Or with the upper limb, the cuff would be placed high on the upper arm.
While the cuff is inflated, blood flow restriction training can be done in several ways:
In this situation the cuff is inflated while the limb is at rest, so no movements are done while the cuff is inflated. This could be useful in the early stages after surgery when there is a lot of swelling and pain, and exercise is not tolerated and can help to prevent muscle mass loss due to immobilisation. This is usually done in cycles of occlusion and deflation, for example 4s of compression alternated with 4s of relaxation.
In this case the passive BFR is applied as above, but additionally electrical stimulation can be used to create a muscle contraction. This has a greater effect on maintaining or building muscle strength than passive BFR alone. This is usually done with the same cycles of occlusion and deflation as described above.
In this case, BFR would be applied while doing a short period of low intensity walking, for example 5-20 minutes. This can be useful to improve muscle strength and aerobic capacity in the early phase after surgery. During this, the cuff can be inflated during the entire time, or in cycles of occlusion and deflation as above.
In this situation the BFR would be combined while doing strength exercises, for example on the leg press machine. Where normally this would need to be done at high loads (more than 70% of your maximal strength), with BFR this can be done at much lower loads (around 20-30% of your maximal strength). Usually, a protocol of 75 repetitions is used, with the first set being 30 repetitions and three further sets at 15 repetitions, with 30-60 seconds of rest in between. During active BFR, cuff stays inflated for the entire exercise.
An additional benefit of BFR over regular high intensity training is that it usually also gives pain relief directly after the session.
While BFR can be a great tool in several types of patients and is generally extremely safe, we have to be cautious when using this in certain patients, especially those with vascular conditions. Some contra-indications for BFR include: a history of deep vein thrombosis, clotting disorders, fever, high blood pressure over 180/100, higher class arrythmias and coronary ischemia, and pregnancy. Reported side effects (although quite low in occurrence) can be fainting and dizziness, numbness, pain and discomfort, delayed onset muscle soreness. In these cases, the pressure may need to be lowered.
In summary, blood flow restriction is generally extremely safe and can be a great tool to optimize the rehabilitation process. Our team is looking forward to start implementing this with you in your rehab program.