I am Dr. Eric Cobb from Z-Health Performance, and today we’re continuing our isometric series, looking at building either maximum strength or hypertrophy and the protocols that seem to show up the most in the literature associated with this. Now, if you’re new to Z-Health, we are a brain-based education company. We specialize in digging through emerging research, finding the nuance and detail that really matters that you can apply practically today to your own body or to your clients.
So if you are a movement professional, a doctor, a therapist, or a coach, I sure subscribe and check out our free resources. For the last few weeks, I’ve been talking about isometrics and some amazingly cool practical tips that are now showing up as we get deeper and deeper into the research literature over the last really five years or so, I’m shooting this because we just released the Brain-based practitioners guide, our membership guide to isometrics ideas that you can apply immediately.
So we’ve already covered some different things about should I do long or short, isometrics yielding versus overcoming. What if I have some sensory issues? So if you haven’t watched the other videos in this series, go back and check ’em out. But today I wanna go back to basics. I wanna talk about building strength or increasing muscular size.
So maximum strength or hypertrophy I’ve read, you know, and seen for many, many years. People say, well, can isometrics, actually do hypertrophy? Can they make you stronger? The answer is unequivocally yes. And in many cases the strength development is actually faster in some ways than dynamic exercise. And hypertrophy can also be very significant, but you have to do the protocols correctly, and they are very different.
What I see a lot of times is that people will start doing isometrics as a part of a training program, and they’re doing them incorrectly. They actually don’t know what they’re doing so they’ll just basically do the same kind of exercise over and over. And haphazard application of science typically leads to haphazard results. So let’s solve that today.
Maximum strength development. First thing I want you to know is that if you want to work on building maximum strength, you should be doing your isometrics at long muscle lengths. Over and over, this has been showing up in different studies, so if you have to guess, go with a long muscle link. This means though that you don’t have issues that preclude doing this.
Go back and watch the information about sensory issues or lack of neural drive or coordination issues. Those may change whether you choose a long or short muscle length. But purely for strength development, think long muscle length.
Next, we have to know how hard are we gonna contract? What’s the intensity? Well, if you’re trying to get stronger, guess what Maximum contraction you need to be above 90% of what you are capable of doing. So in general, I’m just asking people to pull as hard as they can while remaining safe. And this is one of the big issues. Long muscle lengths combined with extremely strong contractions, take some time to build up to because the brain may not feel safe there. So this is not something I recommend jumping into immediately, I normally will start letting my clients who are somewhat deconditioned, or if we’re going through a rehab process, we will start at mid-range where they’re strongest and over a few weeks, progress them to doing 90 plus percent contractions in long muscle lengths. So be careful with your body.
Now the next thing we have to know is if I’m gonna contract that hard, how long do I hold it? Well, this is how things work Normally, if we’re going as hard as we can, we can’t do it very long. So your contraction time needs to be between three and five seconds.
So you’re gonna do a 90 plus percent contraction for three to five seconds, and then you’re gonna stop and you’re gonna rest, but only for five to 10 seconds. And then you’re gonna do it again, and you will repeat that until you hit five reps. Then you’re gonna take a three-minute break, and you’re gonna do that two to three more times. So again, I said a lot of people apply isometrics, hazardly, they’ve read somewhere years ago that, hey, a six second isometric is all you need to do.
Actually, no. And what we’re seeing again is if I’m doing five repetitions of three seconds, that’s 15 seconds per set and I’m doing three to four of those. So 45 to 60 seconds of near maximal contraction. Most people when I first ask ’em to do that after the second set, they’re like, I’m done. I can’t go in anymore.
So one of the reasons we see people struggling with building maximum strength with isometrics again, is that they’re just not working their way up into an appropriate protocol because it’s difficult. What is cool is that if you look at the research, the amount of strength that people can generate from doing this for usually between seven to maybe 12 to 16 weeks, training two to three times a week, you will see strength improvements that range anywhere from only 5%, which is at the very, very minimum up to 91% over the course of two to three months or four months. That is staggering. So this is again, a joint-friendly, safe way for people to get a lot stronger very, very quickly without them having to go through a lot of, strong learning curve related to different types of lifts.
So I love using isometrics for maximal strength. There are other reasons I might do it as well for specific athletes, but that’s the idea there.
Now, let’s compare that to hypertrophy. Hypertrophy is kind of in the fitness and I wanna look better. Can I use isometrics to increase muscular size or change the shape a little bit? Once again, the answer is yes, but a different protocol Here is the only similarity.
The only similarity is going to be that both for maximum strength and hypertrophy, we want to be doing long muscle length in both cases for strength and muscular growth, this seems to work better. The difference is number one in the intensity. So for maximum strength, we’re 90 plus percent. For hypertrophy, we want to be around 70 to 75%. Intensity doesn’t really matter that much if all I’m trying to do is increase muscular growth.
What matters is the time. So for maximum strength, we were doing 90 plus percent for three to five seconds for hypertrophy, I’m gonna be doing around 70%. So in my head I go, okay, what would be a 10? What would be then a five? What would be a seven? Right about there? That’s my my baseline.
If you have cool equipment and you can measure it, that’s great, but you can also go on a one to 10 scale on your effort level. So I’m gonna hit about a seven to a seven and a half, but now I’m gonna hold it for a long time. The idea for us to create hypertrophy is that we need to be aiming to reach somewhere between 80 and 150 seconds of that amount of tension, however we get there.
What is normally seen in the literature is that a few long hold isometrics at 70 to 75% is most ideal. So what that would look like would be maybe I say, okay, I’m gonna go for four repetitions of 30 seconds. So I’m working on my right bicep. I’m at a long muscle length, I’m gonna contract to a seven to a seven and a half, and I set my timer and it’s gonna count down 30 seconds, and then I’m gonna rest. How long do I rest? Not very long. You’re gonna rest for 10 to 15 seconds and then you’re gonna do it again. And what you will find is that by the time you hit typically that second, third, and fourth, 30 second period, that muscle is really burning. It’s really starting to fatigue, and it is that time under tension and that prolonged holding that seems to promote the highest level of hypertrophy. They have compared this where they said, all right, we’re gonna do four sets of 30 seconds, that’s 120. And then they do, or 20 sets of six seconds, also 120. And what they found when they compare them is that the longer holds seem to do a better job of increasing hypertrophy.
So in that particular case, the rest periods and everything don’t really matter. What we’re aiming for is we want to just maximize that time under tension, hopefully hitting that 120 to 150 range. If you’re going a little bit harder, maybe down around the 80 second range.
So for hypertrophy, we have a very different look, a very different style of isometric, and it is much more challenging in many ways. When I want to think about, okay, what do I already know from these other videos? Well, from, or something that’s really long hold, I’m probably gonna need to use an overcoming isometric because we have typically doubled the endurance of a yielding isometric.
So in all the videos that we’ve shot so far, they’re little details that you can start to think through that will help you really refine your programming for yourself and for your clients. Because our job, again, is to save time. The faster people see results, the more inspired they become to continue doing the work that they need to do to be the person that they want to be.
Alright, so this is one of the reasons we love this stuff. We love the literature, we love the detail because again, my job is help you coach your clients to be their best as fast as possible. And that’s why we have fallen in love over the last 20 years with neurology. So I hope you find this really interesting and useful, and like I said, if you are a professional and you have found this series interesting, be sure to check out our channel and resources on the web.