“It’s like riding a bike.” We use this phrase all the time when we talk about things that come seemingly automatic for the body. Whether it’s swinging a baseball bat for the first time all winter, throwing a perfect spiral in a backyard game of football, or actually going for a bike ride, the body has the astonishing capability of being able to complete previously-learned tasks very efficiently, even if those tasks haven’t been done in a few weeks, months, or even years! The same holds true in the weight room. When you hit the weights for the first time after a break, you might notice that your muscles bounce back faster than they did when you first started working out. Most people use the term “muscle memory” to explain this phenomenon.
However, this phrase isn’t actually accurate, and the actual process entails a much more interesting process than you might think.
Any time the body completes a movement, whether it’s writing your name or deadlifting 300 pounds, the brain sends an electrical signal to the muscle fibers that are responsible for completing the action. Once the signal reaches the neuromuscular junction (the location where a motor neuron connects with all of the muscle fibers that it controls), the muscle fibers are stimulated, and the action is completed. Over time, if this particular action is repeated numerous times, a neuromuscular pathway is created so that the brain can communicate to the appropriate muscles as quickly and efficiently as possible. This process is separate from the idea that our muscles “remember” the action and just do it automatically themselves.
This phenomenon can be described in a different way. Let’s say you are needing to get through a dense forest in order to get to your grandma’s house. The first time you get to the forest, you have never seen it before, and so you are not sure what the most efficient route is, forcing you to take quite a while to get through to the other side. Over time, after you have made the trip multiple times, you begin to notice that there is a shorter, easier route that you can take that makes your trip a lot quicker. Once you start using this route over and over again, you start wearing a path on the ground from walking the same way every time you journey through the woods. Soon, you get to the point where you are able to complete the task of getting to grandma’s house very easily and quickly, not because you have to remember how to do it each time, but because you just simply follow the pathway that you’ve created by practicing the journey time and
One last key point that is helpful to keep in mind, is how the body reacts physiologically after coming back from a period of time-off, or detraining. When the body is regularly doing resistance training, scientists have discovered that one of the adaptations that occurs is the addition of cell nuclei in the muscle fiber cells. It was found that the stimulus placed on the muscle cells, from the added resistance of the weights you lift, actually forces the cells to create new nuclei in each muscle cell. This adaptation occurs so that the nuclei can elicit more protein synthesis to take place, which in turn grows the muscle belly bigger and stronger. If you have to stop training for a period of time, like in the case of injury, the newly-formed nuclei that you created while you were regularly training never goes away; they just stay dormant. Once you resume training, your body can skip the first step of creating new nuclei, and go right back to where it left off before you took your break! Therefore, the body performs better after going through a period of detraining, not because the muscles themselves “remember” how to do an action, but because of the physiological changes that occur in the body as a result of the previously sustained regular resistance training.
As is the case with so much in the world of exercise and resistance training, there are quite a few misnomers and myths out there that are used to describe how the body adapts to exercise. While “muscle memory” might be a quick alliterative way of explaining the body’s efficiency, we can now see how sorely lacking it is in explaining the true phenomenon of the body’s ability to adapt to exercise. Additionally, now that you know a little bit about the ins and outs of how neuromuscular pathways and muscle adaptations truly work through consistent training, we hope that you can put to rest an inaccurate phrase with a different one that is just as popular and much more applicable: “practice makes perfect!”
Joe Gernetzke CSCS