If you want to find out what you’re made of, then grab a pair of resistance bands or some medical tubing and read on to find out what that blood flow restricted method (BFR) can do that almost no other method of training can do…
BFR Training: What is it, and why does it work? Like everything in fitness, we’re manipulating a survival mechanism
We tend to think a little too simplistically when we’re thinking of our muscles, we usually think of them as entire muscles like the biceps or the triceps, deltoids, hamstrings etc. and we tend to think that if we flex that muscle or use it, that we’re using the whole thing, unfortunately it doesn’t really work that way. Our muscles are actually made up of hundreds to thousands of independent contractile groups within the muscle belly, these groups are called motor units, and you almost never contract all these individual subunits of the muscle at the same time, in fact if you did contract them all your muscles can create enough force to serious damage themselves and sometimes rip the muscle right off the bone. As we approach our 1 rep max, we approach the highest amount of motor unit recruitment we can reach voluntarily – which may be around 65-70% of the available muscle fibre in the untrained and around 90% in the highly trained.
Fun fact: There’s really only two ways to get 100% motor unit recruitment, A) you must perceive that you or someone else is truly in a life or death situation (this explains those stories where 65 year old ladies pull cars off victims in motor vehicle accidents) or B) Using external electricity like an electrostim machine or getting electrocuted – I probably wouldn’t recommend either scenario
So in the name of the preservation of energy and not ripping our muscles off the bone, our brain is hardwired to always use the smallest amount of muscle, and the smallest motor units to do the job – this sucks if we want to maximally develop the muscle because we want to develop all the fibres! Sure we can keep adding weight to the bar and we’ll recruit more and more of the muscle, but, it comes with a cost, how many times can you actually do your 1 rep max? Well if it’s a true 1 rep max, just once. 1 rep, no matter how heavy, isn’t going to develop much muscle if you can only do it once, but what if there was another way to hit those big motor units that are normally saved for extremely heavy events? There is, and it’s called the blood flow restricted (BFR) method, or “occlusion training”
One of the things about the smaller motor units is that they are highly resistant to fatigue, this is why your arm doesn’t gas out after curling food to your mouth with a fork at every meal, but in order to resist this fatigue, they need oxygen, and that oxygen gets delivered by the blood. So when we cut the blood flow off, the small muscle fibres that normally would handle the lighter weights literally cease to function, leaving the big, normally untouched fibres to take over the load, and now we can hit them with a ton of reps. How many reps? The research right now is varied, but somewhere in the 100-125 total rep range seems to be the sweet spot.
So we’re hitting some new muscles fibres with a ton of reps that wouldn’t normally get them, but BFR training offers another muscle building advantage – it creates a ton of metabolic stress, which is one of the three main methods of muscle growth. The blood normally carries in oxygen and nutrients, but it also shuttles away the metabolites (aka the unwanted by-products of muscle contraction) away from the muscle. Normally theses metabolites are shuttled away from the blood fairly quickly, but when we exercise these by-products tend to build up a little faster and therefore exist in higher concentrations before the blood can take them away and shuttle them to liver to be turned into cool things or are filtered out by the kidneys. In standard conditions, the higher the concentration of these by-products, the more work we did, and the more likely it is that we created some serious muscular damage that needs to be repaired. This build up of by-products is one of the things that signals to the brain that we just did something that posed a threat to our survival, and it better do something about it before it happens again. When we block off the blood from leaving the muscle, these by-products build up in concentrations that really can’t happen under normal conditions, BUT, we really haven’t done anywhere near the damage that these concentrations would indicate. Regardless, the brain responds as if that amount of damage had been done – and viola, you get a huge muscle building response!
OK, sounds cool, but how do you do it?
First, let’s get through the disclaimers:
- I warned you this is one of the most painful ways to build muscle, and I wasn’t kidding, those last few sets are going to be absolute agony, and there’s going to be a burn you’ve never felt before.
- This method is for aesthetic purposes and/or athletes recovering from injury, it builds more mass than strength, and if used constantly could skew the strength to weight ratio in the wrong direction
Here’s the muscle groups work the best for this type of training:
- Forearm Muscles
You’re going to take a resistance band or some medical tubing, (or really anything you can make a good tourniquet with that won’t come loose as you flex the muscle) and you’re going to tie it around the joint above the working muscle at about a 7/10 tightness – we want the arteries to force blood in and increase intracellular pressure, but we want to block the venous return to the heart. Here’s the pictures from above again:
If you look closely, there are two resistance bands tied around Riley’s legs right in the “crotch line” essentially right below the glute line and around the front of the thigh, this is the band placement for the quads and hamstrings
Here it’s pretty easy to see the bands tied right beneath the shoulders, this is the band placement for the biceps and triceps
My favourite BFR method is to work antagonistic pairs of muscles, meaning that you train the muscle on either side of the joint at the same time so good options would be:
- Quads and Hamstrings:
- A) 5×25 Quad Extensions, no rest
- B) 5×25 Lying Hamstring Curls, no rest
- Biceps and Triceps: 8mins straight, no rest between exercises, don’t count sets
- A) DB Bicep Curl: 10 reps
- B) DB Tricep Extension: 10 reps
- Wrist Extensors and Wrist Flexors:
- A) 8×15 Forearm Concentration Curl
- B) 8×15 Wrist Roller
- Calves and Tibialis Anterior
- A) 10×12 Seated or Standing Calf Raise
- B) 10×12 Toe Raises
You’ll notice that the lower body lifts all use machines, I’d advise using machines as opposed to say doing BFR squats and deadlifts – the stability demands are just too high, and many of those so called stabilizer muscles are made up of a really high degree of oxygen dependent fibres (you do have to stand with them all day after all) so there’s a much higher risk of injury. Plus, when we’re going for metabolic stress, this is where isolation really shines, so stick with machine variants for the lower body, but feel free to use free weight versions of the upper body movements if you’d like. Something that is definitely important to note is that you don’t need to use very much weight with this method! 40-50% of your 1 rep max is plenty and sometimes even less is all that’s needed to make progress with this method. I always smile when one of my clients decides to go hero mode after this warning and grab a set of 30lb dumbbells for the bicep/tricep method outlined above; they usually make it to about 2-3mins before realizing exactly how terrible that life decision was and inevitably have to lower the weight to make it out to the full time. 20lbs for most trained men and 10lbs for most women is going to be plenty to get the job done, and I promise you will see both results and agony at those seemingly minuscule weights. The low weight required to make this method effective is one of the reasons it works for athletes recovering from injuries – you can start with your own bodyweight but still have the brain react as if it had done a full intensity session. Last but not least, rep quality matters! No using momentum or cheating, and make sure to squeeze the muscle as hard as possible with each contraction! You want to wring out the muscle and force all those by-products into the blood stream so they hit the brain’s receptors all at once.
When integrating BFR training into your routine I would stick to a max of 2 sessions per week and always implement it as the very last thing in your training session, with only some moderate cardio after if you have it planned for the day. if you’ve really given this method your all, chances are you won’t want to be doing much after anyways. As always if you have any questions about the BFR method or anything else fitness/sport-training related feel free to comment below or on the Blacksmith Fitness Facebook Page http://www.facebook.com/blacksmithfit