Matt Perryman Matt Perryman

Occlusion, Ischemia, and ‘The Pump’

It’s in vogue these days to hate on bodybuilding and the training methods bodybuilders use. The trend these days is to play up the role of strength-based training and ‘functional’ (sic) training methods, getting away from the older bodybuilding culture that’s dominated the popular conception of weight-lifting since at least the 1960s.

It used to be all about the pump, about feeling and shaping and all of that. These days, it’s more about ensuring proper movement, developing well-rounded fitness, and putting strength-based methods at the center of that balanced program. Specialized goals are then added to that framework, in the same sense that your house can look different from your neighbors even if they have the same blueprints.

I can’t say there’s a real problem with this, because that’s the gist of my philosophy, and in general I think that’s how things should be done. However, this takes us to a dangerous place, a thought process that can be counterproductive; in other words, you don’t want to throw out the baby with the bathwater.

This includes even the most Bro-ish of bodybuilding techniques. I can’t lie here, either. I’ve been guilty of this mentality too; or it least it might seem like it with my pro-strength, pro-rationality views. The reality’s a little different, but people used to thinking in black/white terms tend to label everyone else as thinking in black/white terms too.

Unlike most hardliners, who pick a position and stick with it regardless of evidence or outcomes, I think there’s some utility in almost any training style or approach. And yes, that even includes bodybuilding. It’s too easy these days to write off all of traditional bodybuilding as flawed, outdated, and based on pure mythology.

I think that’s premature, though. And I want to be clear: I’m specifically talking about training methods usually associated with bodybuilding – emphasis on ‘pumping’ the muscle, focusing on muscle isolation and shaping, things like that.

I discussed this to some degree in Maximum Muscle, but I was reminded of this subject yesterday, so I thought I’d write something up. The modern paradigm would write off bodybuilding in favor of ‘functional’ approaches. In response, I point out that ‘functionality’ is entirely dependent on context. For a bodybuilder seeking bigger muscles, anything that makes the muscles grow is the definition of functional.

Please let that soak in. ‘Functional training’ is not flipping tires, climbing ropes, doing cleans with the worst possible form, or kipping pullups. Functional training is whatever improves your functionality in a given goal.

KAATSU!!!! and Occlusion Training

Over in Japan the last 10, 15 years or so, they’ve been experimenting with something called ‘occlusion training’ or ‘ischemic training’. If you don’t pay attention to the research journals, you’ve probably never heard of this, but it goes by the name Kaatsu, which is probably Japanese for ‘powerful cuff of great oxygen deprivation honor’.

Anyway, what they do is occlude the flow of blood into the muscle with these big tight cuffs. It’s like when the doctor takes your blood pressure; imagine how that feels, with the tight cuff around your arm. Not always pleasant, but that’s what occlusion feels like.

These guys have been finding that if you block the flow of blood into the muscle – occlusion of blood flow – that very light loads can suddenly stimulate growth and strength gains. When I say light, I mean light; they’re talking on the order of 30% of the 1RM, where we normally expect to see weights in the 70-90% range used to stimulate growth.

I’ve gone over all that before so I’m not going to rehash the explanations, but that’s very unusual to see actual hypertrophy gains coming from loads that light.

My pet hypothesis, which seems to be backed up in the research, is that there’s a neuromuscular effect going in on response to the acute hypoxia (that is, lack of oxygen). Since the working muscles can’t refuel themselves, they’re fatiguing prematurely in response to even a 30% weight.

When you train to fatigue at 80% 1RM, you’re doing basically the same thing – you’re fatiguing the working muscles, and fatigue translates into neurological changes in how fibers are being recruited. Your nervous system is trying to take up the slack by activating more motor units.

In research, this state of fatigue is called ischemia; the muscle fibers tire out and tend to stiffen up. It’s thought that ischemia contributes to both neurological strength gains (via those recruitment changes) and the growth process by making the fibers more susceptible to eccentric overload on any subsequent reps.

In a way, we can think of occlusion as cutting out the middle man. Instead of requiring a heavy load to reach fatigue and ischemia, you just cut off the blood supply; instant ischemia, and now even light weights represent a sufficient overload to stimulate strength and muscle-mass gains.

Now as I mentioned, Kaatsu research has been using occlusion cuffs – a tourniquet or something like that to cut off the flow of blood into the muscle for the training. It’s not hard to imagine where the limitations come into this. You can tie off an arm or a leg pretty easily; anything in the torso is out of luck without some creative surgical methods.

My point here has never been to endorse that particular technique (although you certainly can). What I want to do is look at the underlying physiological process, and note that there is a mechanism to explain how lighter, but longer-duration and more fatiguing methods can potentially stimulate growth. The outcome of occlusion and the direct stimulation of ischemia is pretty compelling, regardless of how you create that effect.

Note that occlusion/ischemic training isn’t actually getting away from the basic principle of tension-time overload. In normal weight training, we reach a compromise in tension-time by using moderate weights and moderate volumes of work. Occlusion/ischemic training simply represents a different configuration of tension-time; by making the muscles more ‘receptive’ to lighter tensions and then extending the duration of work.

A New Use for ‘Pump’ Training

This brings me to the point of the article. We’re limited in how we can externally stimulate occlusion. But tight cuffs aren’t the only way to cut off blood flow.

Muscle contractions do it too. And with that, you can probably see where I’m going here.

How is it that bodybuilders have always been reputed to train? They’re all about ‘squeezing’ and ‘contracting’ the muscles, about really making sure to ‘feel’ the muscle working. Bodybuilders love their slow, controlled tempos, and really pumping up the muscle with all sorts of extended-tension methods. The failure-training meme got started with this, even, and who can forget Arnold’s obsession with the pump (no matter how much we drink…)?

Because of the occlusion research, there’s now a real basis for explaining how those methods produce results. If you’re a pro-strength hardliner, you’re going to scoff and say it’s ‘virtual’ muscle. Well, that’s kinda true depending on your point of view.

Based on the Kaatsu research, muscle fiber CSA does increase; that is, the muscle does grow. However, unsurprisingly, it seems that most of the CSA gains are the result of so-called sarcoplasmic hypertrophy.

That is, water, glycogen, and the various life-supporting enzymes and organelles of the cellular machinery increase in volume, as opposed to the contractile proteins. This is ‘non-functional’ hypertrophy. But if you’re a bodybuilder, who cares? A bigger muscle is a bigger muscle.

It’s often suggested that the more ’rounded’ or ‘puffier’ look of bodybuilder’s muscles is due to sarcoplasmic hypertrophy. There may actually be some truth to this given that bodybuilders are prone to high-volume, slow-tempo, post-fatigue kinds of training.

What I question, as I always have, is the contribution of such methods to your long-term progress. I’ll discuss that in just a minute.

Occlusion/Ischemic Training Methods

As far as creating the occlusion effect, and deliberately triggering ischemia, that’s easy enough to do. And if the Kaatsu stuff is anything to go by, it doesn’t require anything heavy. To that end, everything here can be done with weights (or resistance if you prefer the broader term; some of these methods are uniquely suited for machines) in the range of 30-50% of a 1RM load. Light and slow is the name of the game.

Slow Tempo and Peak Contraction Sets – Basically, this is just the ‘pumping’ style of training that Arnold was famous for. Slow, deliberate reps, focusing on the ‘squeeze’ of the contraction. The goal here is indeed to keep tension on the working muscles; no relaxation at the top or bottom.

Timed Partials – I say ‘timed’ in the sense that you don’t count reps. You just set aside say 60 seconds, or 90 seconds, and just keep moving slowly over a shortened ROM until the time’s up. This will hurt, especially if you’re not used to it.

Extended Isometrics – And on that same note, there’s really no reason you even have to move the bar. Load up your implement of choice with a 30-50% load, move into position, and just hold it. You could even combine it with the timed partials by holding at 2-3 positions and slowly moving between them, alternating isometric holds and slow partial reps.

Basically any ‘post-fatigue’ bodybuilding methods – Yeah, if ischemia is the goal, then most of every bodybuilder trick, from basic high-volume/slow-tempo/peak-contraction ‘pump’ training to rest-pause, drop-sets, and forced-rep methods actually have a place if you’re after maximum size at any cost.

Anything that has the muscle working up to and past the point of fatigue will be adequate to trigger that response.

In the Bigger Picture

Now, this doesn’t really change the game that much – I haven’t changed my thoughts about keeping big lifts and strength-oriented focus as the foundation of your training. Even if ‘strength’ programming had no other effect, the simple fact is that if you can lift more weights, you can do more work with these methods.

On that same note I also haven’t changed my thoughts about keeping ‘bodybuilding’ methods a secondary emphasis, even if you’re after maximum size. The occlusion/ischemia research just slots in nicely with the idea of ‘bodybuilding-specific training’, and lets you body-buffer types feel a little better about what you’re doing. It also gives a nice scientific basis to the Westside idea of combining heavy lifts with very light stuff, like 5×10, or the timed 30-second rest intervals that Louie’s spoken of.

Given that, there’s two options: either add in the ‘pump’ stuff after your big lifts, as bodybuilding-specific assistance work; or combine it with a simple strength template and slot in ‘bodybuilding’ workouts on the non-strength days. The conditioning templates and the ‘beginner and broken’ templates of mine would mesh with this nicely.

It’s functional for bodybuilding, after all. Also it irritates a lot of STRENGTH RAR!!! hardliners, which I enjoy.