white Fitness icon
Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on tumblr

Blood Flow Restriction in Weight Training – How Does it Work?

Anyone who wants to build muscle mass properly must lift heavy weights to the utmost. Anything less than 65% of the 1-Repetition Maximum (1RM) does not cause any hypertrophic effects, according to the American College of Sports Medicine.

But are these recommendations still timely?

A few years ago, Japanese researchers presented a training method that works with about 20% of the 1RM and make muscles pop up like a piece of bread in the oven.

Is it really possible to stimulate recognizable muscle growth with such a low mechanical stimulus?

In the following, I’ll go more in-depth about the concept of Blood Flow Restriction and explain how it does work and what to pay attention to.

Blood Flow Restriction – Theory

What is Blood Flow Restriction actually?

One way to use low intensities effectively is the so-called Blood Flow Restriction Training (BFR), which is also referred to as occlusion training.

During training, the limbs (legs or arms) are pinched off with elastic bandages to prevent the blood circulation of the muscle. More precisely, the blood should flow into the muscle but not out. Thus, it suppresses the venous blood flow without affecting the arterial and in the meantime carrying out an exercise.

Usually, one orient on very short breaks (30-45 seconds), as well as high repetition numbers (15-30) and removes the bandages only when the exercise is completed.

Of course, you just have to pinch off the muscle that is actually being trained at that particular moment. So if you want to use BFR on your arms, you should not pinch off your thighs obviously;)

When BFR training is applied correctly, similar muscle growth can be achieved with 20-30% intensity as with heavy conventional training. Accordingly, it may not clearly provide a better option but just another tool in your repertoire that you use every now and then.

Now you know, after all, that you can also train with light weights and still achieve good results in some muscle groups.

Why not in all muscle groups?

Some muscles are simply difficult to pinch off and therefore BFR is not feasible there. Although one study found a higher pectoral muscle activation with pinched upper arms, I currently strongly doubt that this activation can provide nearly the same amount of muscle (compared to conventional training).

Nevertheless, there are scenarios in which, for example, bench press is simply not possible. In that case, the BFR for the chest would also be an option to get the most out of the situation.

Why BFR training works so well is still relatively unclear by now. The most important role is probably due to the very high metabolic stress caused by the lack of oxygen.

I will spare the biochemical lecture about the possible causes for its effectiveness because only the most important fact is that it works. However, I would not recommend it to beginners or athletes who are not currently in a competition diet.

When does BFR training make sense at all?

1.) During injuries

The big advantage of BFR training is the low weight that is used.

Depending on the degree of injury, complete muscle preservation or even muscle building is possible without further injuring the damaged structures.

2.) Joint overloads

If your muscles need more volume than your joints can handle, BFR training can be the solution. The low intensities relieve your joints without reducing muscle build-up.

5x5 Training System for More Strength

Especially in the last few weeks of a hard diet, the passive musculoskeletal system is often not in its best condition. Here strategically used BFR training can be quite advantageous to ensure the best possible muscle maintenance.

So, whenever you can handle very low joint loads, but still have to maintain or build muscle, BFR training can make sense.

How much should you pinch off?

Remember, we want to suppress venous blood flow without affecting the arterial.

If you happen to have a pneumatic cuff, you can adjust the pressure to about 100-200 mm / Hg depending on the individual conditions. However, as we do not expect, we simply take an elastic bandage to suppress blood flow.

From a pinch scale of 1-10, a 7 on the legs and a 6 on the arms would be recommended. Where the number 10 is the strongest winding that you would get. You should definitely notice the pressure, but do not feel any pain at rest. For if we suppress the complete blood flow by excessive constriction, this can have a negative effect on the build-up of muscle.

Anyhow, on the other hand, of course, we have no great advantage if the blood can flow as usual.

Where should one pinch off?

The rule of thumb is as high as possible. For the biceps, it would be at the top of the arm and for the thigh just below the buttock fold.

How should one pinch off?

You should wrap the bandage over each other and not next to each other. So do not wind down the arm or the leg spiral-shaped, but install in several layers on top of each other. The probability of influencing the arterial blood flow is thus significantly reduced.

How many repetitions should one do?

Because we usually work with intensities of 20-30%, sets of 15-30 reps are common.

In addition, it would be quite reasonable to go relatively close to muscle failure in order to burden the fast-twitching muscle fibers, which have the greatest growth potential. These turn on when the intensity or the load is very high.

In general, I would recommend BFR training only in isolation exercises. Nevertheless, despite the fact that I would not suggest to do so, leg exercises, such as the squat, are also feasible for BFR training.

However, BFR training does not replace deloads and should always be used with the utmost care when dealing with injuries. You must always be aware that training during an injury is always a balancing act.

If the damaged structure is damaged even more severely, it can mean the end of a whole sports career in the worst case. That’s why I generally recommend taking a break from training to completely heal injuries.

BFR training during an injury is more for people who necessarily “need to” keep their muscles for whatever reason. You have to be able to assess your own individual situation correctly or have it evaluated by a specialist. If you are unsure then I would always play it safe and just take a break.

Nevertheless, it must be mentioned that, depending on the injury, a light workout can also promote regeneration. Exactly this is possible with BFR, because you train with extremely low intensities. As you can see, the topic “BFR training” during an injury is quite individual and has to be decided separately for each case.

DoggCrapp Training System (DC) - Complete Guide 2019

Finally, we clarify the question of whether BFR training can be harmful to your health.

What does the current study situation say?

Before we look at these, I would like to draw your attention to the fact that you should always consult a competent doctor with questions about your health.

This is not a health consultation and merely represents my interpretation of the current study situation.

The current study shows clearly that BFR training seems to be harmless if used correctly. So neither for the cardiovascular system nor the nervous system or even in terms of blood clots, there are currently major concerns from the science.

Important: This statement is only valid for people who are completely healthy and have become accustomed to regular, heavy strength training.

Blood Flow Restriction – Practice

After discussing the BFR training method in theory, we’re finally coming closer to its practice.

What would a concrete BFR training protocol look like?

After you have warmed up, you should do the following protocol:

30 reps -> 15 reps -> 15 reps -> 15 reps

The break times should be kept short, between 30-60 seconds.

If you cannot manage that scheme with 20-25% of your 1RM, you have pinched off too tight or just misjudged your 1RM.

“Manage” here does nohow describe a too heavy burning or anything else, but the achievement of muscle failure before you give up.

Why do I mention that?

Because it will be damn hard and most folks will surrender prematurely even though the weight and strength of the pinch-off have been chosen correctly.

But don’t worry, with time the mental pain tolerance aligns. Until then, you should, of course, take a weight, which can be handled by yourself with a pinch-off of 7/10.

In general, you should be at the end of each set relatively close or at muscle failure. Thus, BFR training is characterized by low intensity combined with very high workload. Of course you can also use other break times, intensities and repetition ranges, but the described protocol is the best researched.

Theoretically, it may also be possible for other methods to yield even better results. But before you take the risk of simply achieving poorer results as with conventional weight training, I suggest that you make a rough estimate.

The fact is that there is nothing “magical” about the scheme. Of course, if you make only 13 instead of 15 repetitions in the last set, that’s no problem at all. As soon as you successfully master the protocol, you simply increase the weight.

The constriction should, of course, be kept as constant as possible.

The last question that we need to clarify now:

How is the volume of BFR training assessed?

Because as already mentioned, the volume arises out of a fairly low intensity and at the same time high workload.

In addition, we know that too low intensities are not optimal for building muscle. Could one now conclude that the training stress is smaller than in 4 “normal” sentences?

By no means, because the constriction creates an extremely high metabolic stress and thus, of course, the completed volume to evaluate differently.

In theory, there is only one way to accurately evaluate the volume in order to compare it to conventional training.

The training stress that developed during BFR training is considered to be approximately constant.

Why can we do that?

The Ultimate Guide to German Volume Training

Because you have to train for a long time with the same weights before you can increase it. Because weight increases at such low intensities, in absolute terms, will never be big. As a rule, one can not simply increase the weight by 1-2% as usual.

Suppose you have a 1RM on the hamstring machine of 100kg. If you choose a 25 percent intensity for your BFR training set, you would need to take 25kg. What would normally be the next higher weight you could ever take? 30kg? Even if you have “only” increased by 5kg, so you would increase the weight directly by 20%. The exact same increase, as from 100kg to 120kg.

Have you ever seen somebody doing bench press for 10 reps at 100kg today and pushing the 120kg ten times tomorrow?

That’s why an increase of 20% would be way too much. But you have no choice, because which leg bending machine can be adjusted from 25kg to 25.25kg?

Therefore you have to train for a longer period of time with the same weights until a bigger jump is possible and for that reason, the resulting training stress can be regarded as approximately constant.

Let’s call this training stress “X”.

If you do any other exercises, you have a total stress of:

Total training stress = X + remaining training stress

With these considerations in mind, there are 3 possible scenarios:

1.) Total required stress = X

If the total stress for optimal muscle growth should be equal to “X” (BFR training stress), you also do not have to add further volume for the hamstrings.

2.) Requires overall stress > X

Of course, if the overall stress for optimal muscle growth is greater than “X,” you’ll also need to do more leg flexion.

In our case, we could integrate Romanian deadlift into our training schedule (prior to BFR training).

By doing so, we manipulate the volume accumulated during the Romanian deadlifts in order to get the overall stress for optimal growth.

Because as already mentioned, the training stress resulting from the BFR training is approximately constant.

3.) Total Stress Required < X

If the total stress for optimal muscle growth is less than “X”, you need to reduce the BFR training and of course not add more volume.

How do we get value for the overall stress needed for optimal muscle growth?

By evaluating our progression, as well as our mood, and applying the input/output scheme.

Basically, we can easily determine if the exercise stress was too much, too little, or just right.

Take home

I hope the article has answered your questions about Blood Flow Restriction and you now have an understandable coherent picture of this training concept. Below I’ll list the most important key facts which should keep in mind:

  • The intensity always describes the percentage value of the 1-RM
  • To be able to express the effort, we use the concept of utilization
  • You should stay in the range of 65-85% most of the time
  • Low intensities are also possible, only then must be granted a very high utilization.
  • Below 30% is likely to occur a significantly worse muscle
  • Exception: In combination with a BFR training
  • Blood Flow Restriction Training (BFR) is particularly suitable for injuries or overloads

Did you already hear about Blood Flow Restriction Training (BFR)? What is your experience so far with it?

Leave a comment below and interact with us and the community!

Thanks for reading, guys


Share on facebook
Share on twitter
Share on linkedin
Share on reddit
Share on tumblr


Hi, I'm Claas. I am a passionate fitness and performance lover. For several years I have been training and developing my personality with dedication, ambition, and commitment to pursue my goals. During this time, I already had the opportunity to support many friends, family members and athletes on their journey to achieve their goals, both athletic or performance driven. Whether about nutrition, training, performance or self-development, for the last few years I was able to steadily improve my knowledge to provide our clientele with all my experience. I believe the key to a happy life, to pursue your goals, overcome challenges and convert your dreams to reality, is based upon mastering our four underlying four pillars; nutrition, fitness, productivity, and mindfulness.

Leave a Comment

Your email address will not be published.

About Emerging Athlete

Hi, we are the Emerging Athletes. We believe the key to a Happy and Successful life depends on mastering four underlying Pillars. Fitness, Nutrition, Productivity, and Mindfulness. Emerging Athlete is here to help You with just that.

Step by step you get better and better. Just keep improving and trust the process.

Free Guides

Related Articles

Scroll to Top


Get our Checklist with 75 High Performance Hacks for FREE!

Become the Best version of yourself