What is blood flow restriction training? Does it help with muscle gain?
Have you ever seen a trainer with a strap on the leg or arm at the gym or on a fitness video? You might be thinking, what is this? Is it useful for building muscle? Or is it no different from the traditional method?
It's perfectly normal to have doubts, after all you don't know much about this training method. However, so far, I believe we can be sure that there are no shortcuts to building muscle. 80% of your muscle gain is determined by these basics:
- Compound exercises that focus on heavy weights
- Reasonable plan design
- Proper recovery and good nutrition
Other than that, some are useful, some are not. The blood flow restriction training method that this article will take you to understand is also something other than this 80%.
After reading this article, you will understand whether blood flow restriction training is right for you and how you can implement it safely and effectively.
What is blood flow restriction training?
The blood flow restriction training method is an imported product, which is called Blood Flow Restriction Training in foreign countries, so I will be referred to as BFR below.
Literally, BFR refers to restricting blood flow to muscles in some way during training. However, BFR does not completely block blood flow to the muscles, it simply slows the flow of blood from the muscles to the heart.
Principles of BFR
Blood is the body's system for transporting oxygen, nutrients, glucose, hormones, and other substances, which is why muscles need a steady flow of blood to work.
Your heart pumps blood to the muscles through arteries, and the blood returns to the heart through veins.
When you do strength training, especially at higher reps, the blood flow from the heart to the muscles exceeds the blood flow from the muscles to the heart. That's part of the reason we get that pump in training.
When you're resting between sets, the pump is lessened as arterial blood flow drops and blood slowly drains from congested muscles back to the heart. The purpose of BFR is to prolong the time of the pump, which is mainly achieved by tying an elastic belt to the limbs.
Can BFR help muscle growth?
The answer is yes, and there are several ways to do it, let's take a look at each.
When you're doing strength training, your muscle cells burn energy much faster than usual. At this point, metabolic byproducts also build up faster than the body can remove them. Some of these molecules act as anabolic signals, telling your body to build muscle and strength.
Technically, this process is known as "metabolic stress," and it's one of the three major components of muscle growth.
Because BFR slows the excretion of these metabolic byproducts from the muscle, it allows these metabolic byproducts to remain in the muscle cell for a longer period of time, resulting in a greater anabolic effect on the muscle cell. In other words, BFR amplifies the muscle-building effects of metabolic stress.
Resistance training also causes cells to expand, filling them with fluid and nutrients. This is called "cell swelling," and it also signals muscle growth . Therefore, BFR also enhances muscle building by increasing the time muscle cells spend in a swollen state.
Research has also shown that BFR can enhance genetic signaling pathways associated with muscle growth.
Your body uses a complex network of chemical messengers to tell cells to grow or shrink. One that tells cells to grow is a target protein called mTOR, and another that tells muscles to shrink is a protein called myostatin. BFR, on the other hand, increases mTOR levels and lowers myostatin protein levels, creating a more favorable environment for muscle growth in the body.
Finally, we know that when building muscle, you need to be at or near failure to achieve better results. And if we regularly exhaust all muscles, our ability to recover will be greatly reduced (especially some multi-joint compound movements). This is where BFR can help —although BFR by itself does not increase muscle activation over traditional training, it allows you to achieve higher levels of activation with less muscle damage  ].
This is similar to the "rest-pause" method, which "tricks" your muscle into telling it you're using heavier weights.
Overall, BFR has the following benefits:
- By using lighter weights, there's a lot less stress on your tendons, ligaments, and joints, and you'll be able to accomplish more volume with less risk of injury. This is even more important for people who are already injured or who have joint pain because they can train effectively without exacerbating the injury.
- If you have some training experience, research has also shown that adding BFR sets to traditional sets can improve strength levels compared to heavy training alone .
- If for some reason you don't want to train with heavy weights, you can use BFR for an effective but less stressful workout.
So, as you can see, it's still helpful to include BFR in your training program. But seeing this, you may have a problem, that is its security.
Is BFR safe?
Reducing blood supply to the muscles during training doesn't sound like a good thing, but studies have found no evidence that BFR is dangerous .
It actually makes sense when you think about it, because it only involves reducing the rate at which blood flows out of the muscle, not preventing blood from entering the muscle.
This means that the band shouldn't be too tight when you tie it around your extremities (more on that below), but it's also easy to do. If you tie too tightly and cause some problems, you will feel very uncomfortable and lose consciousness in your limbs.
And even if you're a "no pain, no gain" type of person, studies have shown that you have to completely cut off blood flow to your extremities within two hours to cause nerve and muscle damage .
So there's nothing more dangerous about BFR, and you can rest assured if you want to add it to your plan.
How to use BFR correctly?
First of all, you need to understand that BFR is only suitable for training the four limbs, that is, the arms and thighs, because you have no way to limit the blood flow of other large muscle groups.
Quick-release medical tourniquets are best for the arms, while elastic knee pads or resistance bands are usually best for the legs.
So what should you pay attention to when tying it? Here are some key points:
- If you're strapping your arms, make sure the straps are under your armpits.
- If you are tying thighs, make sure the straps are a little under the base of your thighs.
- As for the degree of tightness, if 10 is a perfect score, it is probably 7-9.
When you have the tools and know how to use them properly, you can get started.
Be careful though, don't drastically change your current training program, the BFR is the icing on the cake, not your focus. That said, you should still start with heavy compound exercises, because they are irreplaceable.
You should put the BFR in a later position in the workout, i.e. for assistive movements such as bicep curls, rope presses, leg extensions, or leg curls.
Start with a weight you can do 20-30 reps, and do 3-5 sets per workout.
Common mistakes about BFR
Although BFR seems relatively simple, there are still many people who are prone to mistakes.
Mistake 1: Including BFR too early in the plan
Studies have shown that beginners are less beneficial to BFR than advanced trainers . The reason is very simple. When you first start strength training, your body responds very greatly, and you can do the basic movements well.
Therefore, if you have less than one year of training experience, then there is no need to use BFR.
There is one exception, though, and that is injuries. If you're a novice, but have an injury, you can use BFR to train while recovering.
Mistake 2: Tie too tightly
Remember, you don't need to completely block blood flow. You just need enough pressure to restrict blood flow back to the heart, but it doesn't need to be too much. As I mentioned earlier, a tightness of 7-9 is fine.
Mistake 3: Too much weight
On your first attempt at BFR, you will find that you burn out very quickly. Therefore, be conservative in weight selection.
Mistake 4; Doing only BFR training
I must stress again that BFR training is not a substitute for traditional strength training. While it does create more metabolic stress, metabolic stress is far less important for building muscle than mechanical tension.
In addition, there are some limitations to the muscle groups that BFR can use.
Blood flow restriction training is a relatively advanced training method, which mainly affects muscle growth through the principle of metabolic stress. When used correctly, BFR can give you certain benefits, especially in recovery training during an injury.
However, there is absolutely no need for beginners to use the BFR training method, just do the basics. If you're going to use BFR, make sure the straps aren't too tight, and try to use them on single-joint movements without too much weight.
Still have questions about BFR? Or if you have anything to add, please let me know.
Yasuda T , Loenneke J P , Thiebaud R S , et al. Effects of detraining after blood flow-restricted low-intensity concentric or eccentric training on muscle size and strength[J]. The Journal of Physiological Sciences, 2015, 65(1):139-144.
Yudai T , Yutaka N , Seiji A , et al. Rapid increase in plasma growth hormone after, low-intensity resistance exercise with vascular occlusion[J]. Journal of Applied Physiology, 2000, 88(1):61-65.
Luebbers PE, Fry AC, Kriley LM, Butler MS.The effects of a 7-week practical blood flow restriction program on well-trained collegiate athletes.J Strength Cond Res. 2014 Aug;28(8):2270-80.
Loenneke JP, Wilson JM, Wilson GJ, Pujol TJ, Bemben MG.Potential safety issues with blood flow restriction training.Scand J Med Sci Sports. 2011 Aug;21(4):510-8.
Lee C , Porter K M , Hodgetts T J . Tourniquet use in the civilian prehospital setting[J]. Emergency Medicine Journal, 2007, 24(8):584-587.
Yasuda T, Ogasawara R, Sakamaki M, Ozaki H, Sato Y, Abe T.Combined effects of low-intensity blood flow restriction training and high-intensity resistance training on muscle strength and size.Eur J Appl Physiol. 2011 Oct;111(10):2525-33.