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CNS and Rotating Exercises

I was wondering what everyone’s thoughts are on the role of your CNS when building muscle and whether exercises/techniques should be changed frequently or kept constant for a long period of time when trying to build muscle. I’ve heard a couple different thoughts on it:

  1. When doing a new exercise, there will be a period of a couple workouts where you will get stronger (more reps and or weight), but it’s not representative of having built any more muscle, but rather just CNS and coordination improvement. After this point, the exercise will better stimulate the muscle and any increase in strength may be representative of an increase in muscle, so it should be kept constant.

  2. Exercises/techniques should be changed frequently, because the goal is building muscle, not lifting more weight. By changing frequently, you’re constantly challenging the muscle, forcing it to adapt. This could be anything from different techniques, like 1.5 reps, putting the exercise in a different order in the workout, or changing the exercise all together.

Generally, I’ve fallen in the first camp, where I’ll find an exercise I like and ride it out for months, but there are some counter points. For the compound lifts, technique and CNS efficiency plays such a big role that you can see strength improvements for a long time without actually building much more muscle. For isolation exercises, maybe that extra rep was because the reps were done a bit faster, were cheated just a bit, or otherwise were not because you were actually stronger. I’ve noticed this myself, in that I’ll think I’m getting stronger, but decide to clean up my form and end up having to drop the weight almost to where I started.

I’m finding the second camp more and more intriguing. Instead of “worrying” about reps/weight, once the lift stalls, switch it up. That way you’ll likely still see some fairly regular improvement just focusing on the muscle and exercise.

I’m not sure if any this makes sense. I’m pretty bagged right now and these are just some thoughts I’ve been throwing around in my head.

People have gotten big and strong changing exercises weekly, never changing exercises, focussing nearly entirely on one movement and nearly entirely on assistance.

Suck it and see, you won’t shrivel into nothingness

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Yeah, for sure. I’m wondering what you think, though.

I’m not looking for what I should do; it’s just a topic for discussion.

Several different Performance/Strength coaches have said that people are different. Some people love new stuff, frequent changes, and “novel stimulation.” They need the newness, and they maybe learn by the differences from cycling through variations.

Other people get confused and upset by frequent changes or things feeling different. They need longer periods of time with the same stuff, and fewer changes.

Thibadeau even says that people can be different depending on life circumstances. Like a dude could love changes and variety and new stuff when things are going well in his personal life. But then when the same dude was tired, stressed and bust the variety would be too much and overwhelm dude. And in those circumstances a more consistent program would work better.

But most of the guys I’ve heard talk about these theories are Strength Coaches or Power Lifting guys or more concerned with performance vs building straight muscles.

The professional body builder around here swears that bodybuilders find good lifts they like and just stick with them until forever.

So who knows for sure? Anyway, it seems obvious that:

“Big” lifts have a higher potential to go “up.” You could probably add 10-15 pounds to your Smith machine incline press over a training cycle and still be working your shoulders.

“Small” isolation lifts have less potential to go up. If your delt raises go from 15 pounds to 30 pounds in a month, your probably not working the side delts anymore.

A few lifts, like skull crushers, upright rows and stiff leg deadlifts are notorious for messing people up and should maybe be rotated extra frequently so the weights don’t get heavy enough to cause problems.

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You’re right about individual difference/preferences. I think believing in your training probably trumps a lot of what may or may not be better in theory.

If someone changes too frequently, they may lose some motivation. I know, for me, if I change too frequently, then I lose a sense of flow. I tend to find an exercise that feels good, then go with it until it no longer feels right. This usually happens with isolation exercises, because a small jump in reps/weight means a larger jump in work percentage (which you said). After a while, I’ll feel my form slipping and I know, even though the weight’s going up, its due to factors other than an increase in muscle and it’s time to switch things up.

I think instead of building a routine based of CNS considerations, it’s better to build it around what will motivate you. What I just try to keep in mind is that the first couple of weeks of a new exercise will likely improve week to week, but that doesn’t necessarily mean much more than I’m getting better at performing the exercise. Its the improvements after this point that matter.

Where CNS considerations may play a role, from a bodybuilding view, is when someone can’t isolate the muscle they’re trying to. Take a biceps curl. An untrained person who does a lot of manual labour may be able to lift the same amount of weight as a trained person, because they’re used to lifting weight in a work setting. The goal there, though, isn’t to isolate the biceps, but to lift the weight, so they may be inadvertently using more forearm and shoulder muscle or have a difficult time keeping it strict, because they’ve trained themselves not to. They may have to find a different exercise that they can use to learn to isolate the muscle first. That could be a form of CNS training.

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