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Episode 252: The Myth Of Bilateral Training

Video Highlights

- Relevant brain basics
- Unilateral training concept basics
- How to test on yourself

Today what we’re going to talk about is why training for symmetry in the gym may be one of the worse mistakes that you can make.

One of the biggest things that we are trying to bring into the health and fitness industry is an extreme focus on the neuroscience of movement and the neuroscience of training.

One of the things that we see constantly in gym settings around the world is that people are convinced that they need to always be working symmetrically, meaning if I do 10 repetitions of exercise on my right side, I should do 10 repetitions on my left side.

A lot of people love barbells and other things that force their body to move bilaterally all the time.

Now, we love all forms of exercise so don’t hear me saying that I don’t like barbells and I don’t like squats or any of that stuff because I do, but what I need you to understand is that depending on your relative level of health and very importantly, your relative level of asymmetry coming into training, focusing on symmetry can actually cause more problems than good.

What we want to talk about today is a little bit of the neurology behind that and show you where things can go badly wrong for people. Then we’re going to show you a couple of quick tests that you can perform on your own to figure out hey, do I need to take a big step back and figure out should I be training more one side of my body as opposed to both at least for a few weeks to a month to bring symmetry back into the picture.

That’s why I wanted to go over this, because I see so many people continually hurting themselves by focusing on symmetry all the time.

Let’s go over some neurology. If you put your left hand out in front of you and you just open and close, make a fist, I want to talk through the neural pathways that are happening here.

When I move my left hand that information is going to travel up the nerves of my left arm, it’s going to go to my spinal cord, it’s going to ascend to what’s called the cerebellum which is the little brain at the back of the big brain on the left side. When the left side cerebellum gets nice and happy and active, it activates the opposite side of the cortex. So when I move my left hand, that’s eventually going to cause the right side of my brain to become active.

Why that is so important is first of all from a pain control perspective. Whenever I move my left hand and I activate the right side of my brain, the right side of my brain has an outflow through my brain stem that goes down the right side of my body. Whenever the right side of my brain sends signals to my right brain stem and to the right side of my body one of its primary jobs is to keep pain from occurring so that’s pain inhibition.

The second major thing it does is it controls muscle tone on this side. Why this is kind of important to recognize is, let’s say I have a right shoulder problem. I have pain in my right shoulder. Well, pain in my right shoulder usually comes about for a lot of different reasons but let’s say it’s because I have had lousy muscle tone and as a result of bad muscle tone the rhythm of the movement, the way the joints are supposed to function together is off and so something is getting pinched as I raise my arm up or I’m doing one of these things. You’ll hear it called impingement.

Let’s say that I have impingement issues on the right side. In most cases you go to a well meaning therapist or doctor or training or whoever, and we say hey, let’s exercise — which side? Oh, the injured side. Let’s do a lot of work on that side. We’ll work on your external rotators, we’ll stretch it, we’ll mobilize it, but I want you to go back to thinking about what I said. If I’m constantly exercising my right side that’s painful, when I move it the flow path of nerves is from my right shoulder to my right cerebellum to my left cortex which should improve pain where? On the left side of my body.

This is very complicated and I’m making it overly simplistic, but what we see constantly is people going into a gym, they go oh, you know, I have problems over here, I need to make sure that I really exercise that side to keep it strong and healthy. That’s true, but you need to add the word “eventually” to it. What we may need to do is improve neural output to that side by focusing on the opposite side of the body and now all of a sudden really cool stuff starts to happen.

Medium shot of man's torso as he does dumbbell curls

That’s kind of the basics of the neurology behind this, as I said it’s kind of complex. We have a lot of information available to you about it in a lot of our courses, but what I want to do right now is take one step and just say, let’s make it practical. Let’s see how your body responds to loading one side and then the other and then you can choose for yourself what you want to do in the gym today.

I want you to grab a comfortable working weight of some kind because we’re going to actually test an overhead press. You need to grab a dumbbell or a kettlebell as long as you’re not in pain and we’re going to do a little evaluation.

Put the weight down in front of you and what I want you to do is first of all a movement assessment.

By a movement assessment it can be a bunch of different things. I’m going to choose to use range of motion. I’m going to look at my shoulders. I like to always do this, what I call scarecrow, where I’m going to bring my arms up and I’m going to test my internal rotation on each shoulder. I’m going to do probably five or six reps to get an idea of how tight I feel. Right now my right side actually is pretty tight, left side not so bad but both sides actually feel tighter than normal. I’ve been standing in front of the camera a lot today so it may just be that I’m camera shy.

Testing internal and external rotation, I also like to test abduction, so I’m just thumb on top, elbow locked, trying to get an idea of how tight my shoulders feel. Again they both feel a little tight at the top. I was doing a lot of shoulder exercises yesterday so they’re already a little bit tight from that. Another possible thing I could do is full body rotations, just getting an idea of how comfortably I can rotate and how far I can rotate.

I want you to choose a few range of motion exercises and test them. I want you to be very consistent. Notice and mark how far you can move. Now what we’re going to do, is we’re going to actually take the implement that you’ve chosen and we’re going to do three repetitions of an exercise on one side and then we’re going to retest your range or motion. Then we’re going to do the same thing on the opposite side and just see what happens.

I’m going to use a kettlebell. I’m going to just do a little kettlebell shoulder press and it should be a light weight for you, something that would be like a warm-up weight, so I’ve got something nice and light here. I’m just going to rack the bell. I’m going to go through and I’m just going to do two, actually two repetitions of the exercise. I’m going to set the bell back down, relax, go back to my scarecrow position and see what kind of range of motion change I get. That actually was pretty good. I’m rotating further, my shoulder is moving better and I feel looser. In my case, we know that left-sided work was pretty good. You need to test that for yourself.

Now what we’re going to do, I’m going to test right-sided work. So again, rack the bell, nice and tall. Remember I’m just doing one or two reps here. This gives me the opportunity to not tire myself out in the testing process. So again, give it 10 seconds or so, come back up, reassess, and there we have it. That’s actually quite tight. I’m going to rotate again. Everything’s a little bit tighter working that right side today.

Why is this so important to me? I have been doing neural based work for a very long time. I’m an athlete, I do tons of different strength training modalities, I’ve done tons of different sports. Even for someone like me who spends all their time really focusing on brain-based fitness, things change. There are days where I figure out, I just really need to focus on my left side today. Other times depending on other stressors, I really need to focus on my right side today. A lot of times if I’m healthy, I’m nice and symmetric and I can do both sides.

This is such a key concept, I’m going to recommend that before every training session take two or three of the exercises that you’re planning to do and test left side versus right side. In most cases the people that come to us, we figure out that they need from six to eight weeks of primarily unilateral or single side training to create enough symmetry to get benefit, real benefit from bilateral training.

I really want you to write this down and think about it, particularly if you have nagging issues on one side of your body that have not been responsive to more traditional methods. This is the basics of what we call unilateral versus bilateral training and the neurology behind it, one of the most important concepts that we teach in our kind of new, emerging brain-based approach to fitness.

Thanks for sticking with me through that. I know it’s a lot of neurology to throw at you in a very short period of time.

We’ve already talked about this idea that if you responded really well to unilateral work on one side, you need to start applying that in your workouts. The basic recommendations I make are 70 to 100% of your exercises in any given workout, stay on that unilateral side, do that for two weeks and then reassess. Obviously if you’re getting into this, I’d say reassess every single training session because I believe that’s where the real magic lies.

If you’ve gotten interested in this and this whole idea of brain-based approach to movement and strength training really interests you, because we hear questions about this all the time we actually shot a product around this. It’s a 90-minute basically webinar where I go through the neurology behind unilateral versus bilateral training and we show you a very specific protocol that you can use to go through an entire workout to get an idea of what you or clients are going to respond best to. If you’re interested in that you can click the link below and check it out. Otherwise, let us know how this works for you. We’d love to get your feedback.


VIDEO LINK: https://youtu.be/b5R5Qk76o_c
(This is the link to the Unilateral vs. Bilateral video Dr. Cobb mentions in this week’s blog.)

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