It’s called blood flow restriction training, BFR for short, and it’s an awesome training met
hod. The amount research on it is growing fast, and it’s still looking very promising. On top of that, it doesn’t require ridicoulously expensive equipment and courses to do anymore.
As you know, I study sports science. And sports science researchers at SDU are actually the ones that first introduced me to BFR training – because apparently researchers are higher ranked than students and can kick us out of the gym when they need the space to do “science”.
Us students have also been asked to a participate in a couple of these studies, but as I’m neither male nor uninjured, I couldn’t take part in them.
But it did spark an interest, and I was actually looking to get my own bands for my birthday – particularly because of the huge benefits it has for rehab. Somehow (mindreading?) BFRpro could sense this, and reached out to me, to try out theirs.
So for this post, I’ll be sharing some of the research (sources included, of course) I’ve done on the subject and my personal experience with BFRpro.
I’ll cover the questions that most people have about BFR, like
- What is it? (pretty good and basic question)
- What’s it good for?
- What does the research say?
- Is it safe?
- What do I think of it? Personal experience
- How can I get the equipment?
- How do I get started with BFR?
What is BFR?
BFR is short for blood flow restriction training, but also goes by names like occlusion training, VOT (vascular occlusion moderation training) and kaatsu, which is the japanese word for the training method – the place where it originated (It’s also the name of a brand today). I’ll just call it BFR, short and sweet.
So BFR involves restricting (not cutting off, obviously) the blood flow. You do that by applying a band at the upper arm and upper thigh. Now, blood can reach the muscles (because you’re not cutting off the arteries deeper in the muscle), but stay there longer because the venous blood flow is restricted. This creates a physiological response that stimulates muscle protein synthesis and substantial hypertrophy (fancy talk for more muscles!) – all while lifting a lot lighter weights than what’s usually considered necessary for muscle growth. And this is where it gets interesting:
What’s it good for?
Because you can grow your muscles while not stressing your joints and ligaments with heavy loads, this can be incredibly good for people recovering from an injury or want to prevent one.
As you can see on the graph below (I should become an artist), muscle tissue adapts incredibly fast, while injuring other structures is a pretty bad idea (I’m speaking from personal experience here). Strong muscles can help stabilise the joint and compensate for the injured structure. BFR training let’s you return to training and challenge the muscles faster.
Other areas where BFR can give you an advantage:
- As part of a program with lots training to work the muscles while relieving the joints of extra stress.
- As your travel workout gear. It’s difficult to maintain muscle mass when you’re travelling and don’t have access to a gym (or don’t have as much time). With BFR you don’t even need any extra equipment, just 4 straps that barely takes up any extra room.
- As a way to add variation to your monotone workout program. From time to time I find it hard to be motivated to lifting heavy (it can be fun, but some days it’s just hard). With BFR you only have to use 20-50% of your 1RM, and it’s not hard the same way.
- Because you think it’s fun (that amazing pump feeling). This aspect shouldn’t be neglected when it comes to motivation and long term adherence.
- When you’re going to space. I didn’t come up with this, somebody actually wrote an article about why BFR has potential on long spaceflights. It’s probably good to know when the world ends and we have to become space svangers.
You might also want to read: HOW TO BE MORE CONFIDENT IN THE GYM
What does the research say?
This (obviously) not a rigid systematic review, but I’ll try to bring up some of the most important points from current research without making it too boring.
Traditionally, research on hypertrophy says using a weight heavier than 65% of 1RM is neccessary, while with BFR, loads as low as 20-30% of 1RM can create the same response. This means, if you at most can squat 100 kg for one rep, you’ll have to squat over 65 kg normally. But using BFR, 20-30 kg is enough [source].
Strength can increase significantly too, though less than with traditonal heavy training – which is why I see this as a complimentary form of training, not a replacement for non-injured people.
In terms of why it works, the mechanism on a cellular level aren’t fully understood (the same actually goes for hypertrophy (to a lesser extend), or pretty much any other subject when you dive deep enough into it). Multiple hypotheses are being researched though, which you can read about here if you’re into that kind of stuff. Whatever floats your boat.
One of them is that restricting the returning blood flow leads metabolic byproducts to accumulate – like lactate, which cause an increase in growth hormone and Insuline-like Growth Factor-1 (IGF-1) (both play an important part in hypertrophy). Yet this is more diffiult to research than all the studies that just look into whether or not there is an effect with different people and forms of training, and there’s still a lot to be learned.
This page gives a good overview of the research on BFR and its findings if you want more of the evidence.
You might also want to read: A SUPER HELPFUL GUIDE TO LIFTING LINGO
Is it safe?
Seems like a good thing to check out before you try it, right?
All forms of exercise can be dangerous and cause injury – and long term, not exercising is dangerous too. Basically we’re all going to die. The end.
No, sorry about that. There are a few guidelines for you to follow to avoid any negative effects (and maximise the positive).
- Apply the right amount of pressure: On a scale where 0 is no restriction and 10 is full restriction, 5-7 is the correct pressure (5 upper body, 7 lower body). You should not feel tingling or numbness (read more here) – it’s better to keep the bands too lose than too tight.
- Maximum 15-20 minutes of continous applied pressure. Some recommendations go as low as 10 minutes.
In healthy adults, BFR doesn’t seem to have a negative effect on nerve, risk of blood clots or vascular function [source]. Pretty much all the research is done on young, healthy adults, and it doesn’t seem to be bad when you follow the guidelines. However, if you have high blood pressure, heart problems or something third, I’m not capable of judging whether it’s safe. The research just isn’t there yet [source].
So if you have a history heart disease, hypertension, history of strokes, blood coagulation problems, diabetes, venous insufficency and so on, maybe pass for now (in some cases, traditional strength training isn’t a good idea for people with these problems either).
As always, listen to your body and consult a medical professional when in doubt. Is it necessary for me to add a disclaimer that says try this at your own risk?
I’ll admit that when I first heard about it, I immediately wondered whether it was safe – but after reading up on it and trying it out, it’s no longer a big concern.
The BFR gear I use came with a tiny “manual” that lists these precautions as well as guidelines on corrrect use that you can keep with you as you learn to use the gear.
Speaking of which:
What do I think of it? My experience
I’m really glad I got the chance to blood flow restriction training. It adds some very welcome variation to my workouts. The burn + pump you get from it is pretty darn fun.
As I’ve struggled with knee problems, it’s also allowed me to challenge my body in new ways. For a long time I haven’t been training to failure (or anything close to it), but with BFR it’s possible.
It’s been such a boost for my motivation, and I find it fun to experiment with new ‘BFR finishers’ at the end of my workouts.
The gear I’ve been using is from BFRpro, a great Danish start up.
Both the leg and arm straps are easy to put on and tighten yourself, and they’re comfortable to wear. The arm ones do have buckles, which can get in the way or pinch the skin if you’re not paying attention – but they’re not so wide they limit the movement of your arms.
The leg bands use velcro, so there’s no buckles or flapping straps that can get in the way of movement. It comes with the little guide I mentioned before, all in a little bag so you easily can carry it with you in the gym.
Now, I haven’t been tracking my “progress” so I can “prove” it works to you. I’m not motivated by aesthetical or weight-based goals, so it doesn’t make sense for me to do that. And it doesn’t make sense if my anecdotal “proof” of progress is more important than the base of evidence in this area.
What I can tell you is that I absolutely want to continue using BFR as part of my workouts (I already have been using them at least once a week for a while). I want to experiment with occludded walking, and I’ve brought with me when I stayed for a few days at my parents place.
How can I get the equipment?
Jacob Beerman (Danish expert on strength training) also a thorough breakdown of various types of BFR equipment on the Danish market. Unfortunately it’s in Danish, but it’s worth a read if Google Translate isn’t too terrible (and by the way, BFRpro did very well in the test).
Now, the only question left to be asked is:
How do I get started with BFR training?
You can use pretty much the same exercises for blood flow restriction as you do with normal strength training – you’ll just have to use less weigth (or body weight, which is what I have been doing mostly).
If you’re doing a mix of restricted and non-restricted training, the blood flow restriction training should be performed last.
You can use the 30-15-15-15 protocol to adjust the pressure and/or weight. This means you should be able to do 30 reps, 30 seconds of rest, then 3 more sets of 15 reps with 30 seconds in between. or the following exercises aim for 15 reps per set (remember the total time shouldn’t pass ~15 minutes). You’re should keep the straps on during rest periods, as the effect is reduced otherwise.
Otherwise the usual principles of strength training applies, and you should always adapt your training program to your own goals and current level. The Barbell Physio has a great breakdown of how BFR can be used for different kinds of training here.
Some studies also suggest that BFR has great potential for endurance training, like walking and cycling, where it can increase your muscle mass, strength and VO2 max.
At the time of writing, I’m working on another BFR blog post with sample workouts to show you how it can be done (but it takes a while when I have to shoot the pictures and video). I hope you’ll find it helpful!
You might also want to read: STRENGTH TRAINING FOR BEGINNERS: HOW DO I START LIFTING?
Do you still have questions about blood flow restriction training? Let me know in the comments!
This post was made in collaboration with BFRpro, who kindly sent me their products as a gift
- Blood Flow Restriction: How Does It Work? (PubMed)
- Effects of resistance exercise combined with moderate vascular occlusion on muscular function in humans (PubMed)
- Effects of resistance exercise combined with vascular occlusion on muscle function in athletes (Springer)
- Blood Flow Restriction Training – BfRpro
- Blood flow restriction training – Strength and Conditioning Research
- Relative safety of 4 weeks of blood flow-restricted resistance exercise in young, healthy adults (Pubmed)
- Blood flow-restricted exercise in space (PubMed)
- Exercise and blood flow restriction (PubMed)
- Is Blood Flow Restriction Training Safe? – The Barbell Physio
- A Quick Guide to Blood Flow Restriction (BFR) Training- BfRpro
- Okklusionstræning: Effektiv træning med lette vægte