Occlusion Training (also called Blood Flow Restriction Training or BFR Training) involves using very light weights (20-50% of a 1 rep max weight) along with wrapping straps or bands around a muscle to apply pressure to the veins (similar to blood pressure cuffs) with the goal of restricting (occluding) blood flow out of the muscle.
The straps or bands are NOT tightened enough to restrict arterial blood flow (the blood supply to muscles through arteries coming from the heart).
Essentially you want blood to still go into the muscle but not be able to leave.
By restricting venous blood flow (blood returning from the muscle to the heart through veins), the muscle will swell during an exercise with the incoming blood and the metabolites (the byproducts created during exercise such as lactate, phosphate and hydrogen ions) that cannot leave the muscle because of the vascular restriction.
This causes incredible muscle pumps because of the dramatic volume increase in the muscle (like a balloon). Arnold thinks that’s just fantastic!
These incredible muscle pumps that come from using the light weights supposedly cause similar muscle growth as that seen when training with much heavier weights. Some occlusion training studies even show significant strength increases as well when occlusion training is used as a supplement to normal heavy lifting.
KAATSU Training (Origins of Occlusion Training)
Dr. Yoshiaki Sato of Japan is generally considered the originator of occlusion training and has even patented his exercise methods, which is called KAATSU Training or simply KAATSU.
He studied how to prevent muscle loss and even stimulate muscle growth often while injured. He prescribes very specific pressures that are monitored with what’s called a KAATSU Master device.
How Occlusion Training Stimulates Muscle Growth
It’s generally recognized that for a muscle to grow and get stronger you need to apply a high mechanical stress. That mechanical stress comes from moving heavy weights, typically between 70-85% of a 1 rep max weight.
But occlusion training recommends using very light weights (20-50% of 1 rep max). How the hell can you grow from that?
⇒Through oxygen depletion and metabolic stress⇐
How Oxygen Depletion Can Cause Muscle Growth
By restricting blood flow out of the muscle, the muscle slowly has less oxygen available to it as the exercise continues because the blood can’t return to the heart to get more oxygen.
If you understand the different muscle fiber types, then you know that lifting light weights will primarily use the slow twitch endurance Type 1 muscle fibers. These fibers need oxygen to function and can’t grow that much.
But a muscle is composed of Type 1 and Type 2 muscle fibers. Muscle fiber types are also used in order from slowest (Type 1 – most oxygen dependent) to fastest (Type 2 – do not depend solely on oxygen).
When the oxygen supply is limited, the slow twitch Type 1 muscle fibers fatigue quicker than normal.
Therefore, the fast twitch strong Type 2 muscle fibers (which are not solely dependent on oxygen) must now help to keep moving even very light weights.
Type 2 muscle fibers also have the most potential for growth so using them is obviously good.
What Causes Metabolic Stress in a Muscle?
Muscle growth is generally the result of the repair of the muscle damage that occurs from lifting heavy weights.
But the light weights used in occlusion training don’t cause much muscle damage so muscle growth (hypertrophy) is the result of metabolic stress created in the muscle.
When you perform an exercise, metabolite byproducts such as lactate (the muscle burn) are created and partially removed from the muscle by the blood.
But occlusion training restricts this blood from leaving allowing those byproducts to build up (accumulate) in the working muscle.
The increased concentration of these byproducts causes metabolic stress, which supposedly increases intramuscular (inside the muscle) hormones such as Growth Hormone and IGF-1 (Insulin Like Growth Factor).
Myostatin levels are also reported to decrease because of this stress. Myostatin is very important because it controls the amount of muscle you can build (lower myostatin = more muscle building potential).
Because the muscle is now saturated with these anabolic hormones, you would expect to see growth even with light weights and low mechanical stress.
Benefits of Occlusion Training
- You can use light weights which is good for working around injuries (especially tendinitis).
- You may get more vascular. The veins that are occluded are required to hold more overall blood making them grow and become more visible. This increased vascularity also improves blood flow over time.
- Muscle cell size may increase from the forced muscle volume increase. This makes the muscle more anabolic (more growth potential) because muscle protein synthesis increases as cell size increases.
- It can be a new stimulus, especially for lagging muscles. Generally lagging muscles have restricted blood flow, which limits their growth potential. Blood flow to a muscle is also a key for quicker recovery.
- By flooding the lagging muscle with higher than normal levels of blood and hormones, their growth potential increases.
Best Bodyparts for Occlusion Training
Keep in mind – occlusion training will only work if you can actually occlude the muscle! This means being able to place the straps/bands between the muscle and the heart so you can restrict the blow flow back to the heart.
Most people have success with the calves, legs (quadriceps/hamstrings), arms (biceps/triceps) and forearms since they can all be isolated along a limb itself.
The shoulders (deltoids) can also be occluded as long as you get the straps in the right position before the shoulder joint.
Some things you read also say you can occlude the chest muscles by wrapping the arms but I don’t see that being very effective. Since the chest muscles are on the torso and close to the heart, there is no easy way to place a strap/band across the veins returning to the heart.
Occlusion training for the back will also not be very effective for the same reasons as the chest muscles.
I suppose the neck muscles could also be occluded, but unfortunately the brain won’t like the lack of blood (oxygen).
Occlusion Training By Bodypart
Occlusion Training for the Arms (Biceps/Triceps) – wrap at the narrow top part of the arm through the armpit just below the shoulder joint.
Occlusion Training for the Forearms – wrap at the top of the forearm just below or even right above the elbow joint.
Occlusion Training for the Legs (quadriceps/hamstrings) – wrap at the top of the leg through the groin just below the hip joint.
Occlusion Training for the Calves – wrap at the top of the calf muscle just below or even right above the knee joint.
Occlusion Training for the Shoulders (Deltoids) – wrap through the armpit like for the arms but place the wrap/band over the shoulder instead (before the deltoid muscles).
How to Do Occlusion Training
- Decide which body part you want to train. For most, that’s generally a lagging muscle group but it doesn’t have to be.
- You will need some type of strap or band to apply the restriction. Many times people will just use knee/wrist wraps or ACE bandages. There are also specialty bands/straps you can buy online.
- Start wrapping the straps/bands at the end of the muscle closest to the heart.
- Although some sources prescribe exact pressures that must be applied and measured, the more relaxed recommendations are to wrap to about a 7 out of 10 intensity level (10 being the tightest you can wrap).
- For the smaller muscles (calves, arms, forearms) you may be able to wrap slightly looser and still apply sufficient pressure since the distance the strap/band has to go around is smaller.
- The pressure applied should certainly be uncomfortable, but not very painful or so tight that you restrict all blood flow. If you want to remove the straps/bands even before starting the workout, they are probably too tight.
- If you have noticeable numbness or tingling before starting the exercise, try re-wrapping slightly looser.
- The goal is to apply enough pressure so that you can get a good pump during the exercise that also does not disappear during the short rest periods.
- As the workout progresses the pump/burn should increase to the point that you start to want to remove the straps/bands.
- Do not remove the straps/bands (even during rest periods) until all sets and reps are complete.
Occlusion Training Workout
Since one goal of occlusion training is to increase intramuscular levels of Growth Hormone, it’s best to keep insulin levels low before and during this workout.
High insulin levels can restrict Growth Hormone release. This means you should avoid most carbohydrates and fasting digesting proteins like whey. Save those for right after the workout.
The general occlusion workout recommended by experts such as Dr. Layne Norton is to use a weight that’s 20-50% of your 1 rep max and do the following 5 sets:
- Do the first set to failure (target 30 reps) to flood the muscle with blood/lactate and get a pump.
- Rest 30-60 seconds max to allow only partial muscle recovery.
- Do a second set to failure (should only get around 15 reps this time because of fatigue) and rest 30-60 seconds again.
- Do 3 more sets to failure (hopefully around 10-15 reps each set) while resting 30-60 seconds between all sets.
- Now remove the straps/bands to let the blood flow return to normal.
Since this workout does not cause a lot of muscle damage from heavy weights (mechanical stress), you could do it 3 times a week for a few weeks as a supplement to normal heavy training. You could do it following the heavy workout or on separate days.
Is Occlusion Training Dangerous (Have Side Effects)?
Sure occlusion training can be dangerous. If you apply too much pressure that you restrict all blood flow (like a tourniquet), you could obviously do some serious damage to the muscle.
You could also apply the right pressure but for too long. Blood supply will eventually drop off. As soon as the exercise sets and reps are complete, remove the straps/bands to allow normal blood flow.
Although veins can expand with more blood that’s not allowed to leave, they can become damaged when blood volume is too high leading to possible varicose vein formation. Some bodybuilders in general seem prone to varicose veins.
Since you’re not likely to be measuring the pressures you apply, I would stay on the safe side and apply too little pressure at first and see what results you get. Use the minimum amount of pressure to achieve the goal.
If you have difficulty getting a pump or maintaining it during rest periods, you will need to apply some more pressure by wrapping tighter.