Muscle memory is something most of us have heard mentioned many times.
It often refers to the way in which the brain remembers the repetitive movement of the muscles. For instance, when you play a song on the piano, and instinctively remembering the fingers movements over the keys.
For years bodybuilders would talk about muscle memory, and how it worked. Their theory was that if you exercised regularly the muscles would learn how to perform the exercise and to make it easier.
The idea was that the muscles would remember how to perform the exercise. Even if you had not exercised for a very long time.
The expression “It's like riding a bicycle” seems particularly apt here.
Researchers disagreed that it was the muscles themselves that were memorising the movements, and attributed it to the central nervous system.
When you learn to kick a ball it is the result of your central nervous system coordinating the body through a process known as Motor learning.
What About the Actual Muscles Themselves?
How is it that when a newbie at the gym dedicates a good 6 months to training, bulks up considerably, then forgets the gym for two years, allowing their muscles to atrophy, can go back and regain their muscle strength and bulk back up in a third of the time?
When we hear of muscle memory in relation to exercise training. It is the strength and mass that is regained quickly, not the movement.
So the ‘memory’ isn’t coming from the brain, it is something inherent in the muscle tissue itself.
This is the other type of muscle memory. And it has nothing to do with the brain remembering, it is all down to those fantastic little myocytes.
What are Myocytes?
Myocytes  are more commonly referred to as muscle cells, or muscle fibres, and are the type of cells that make up muscle tissue. They are long, tubular shaped cells that are made up of a combination of different protein formed filaments.
These different filaments are also used to store glycogen and oxygen which is utilised for energy and movement.
Muscles fibres are formed from the joining of myoblasts, which are basically unformed muscle cells.
As each of these myoblasts has its own nucleus. When they join to form a muscle cell, the muscle cell then has numerous nuclei.
It is within these nuclei, that the DNA is stored. And it is now believed that it is within these nuclei that the memory of strength and form are stored.
How Do You Build Muscle?
When you train to build muscle mass and strength, you are actually stressing these muscle fibres. This causes them to be damaged and torn.
Your body then sets about repairing and rebuilding them, Making them stronger and more resilient than before.
This is why they not only become stronger, but visibly larger as well. The ‘memory’ of this strength and mass is stored in the nuclei.
Don't forget that alongside your training you must get plenty of sleep and adequate nutrition to build muscle. Our bulking guide will help with nutrition.
Muscle Memory and Atrophy
Recent studies have now shown that contrary to what we had believed in the past. These nuclei do not atrophy along with the rest of the muscle fibres .
Instead, when the rest of the fibres whither, they remain within the cell as memories of what they have been capable of in the past.
When your body goes through an extended period of disuse. The muscles will slowly atrophy down to the point of necessity.
The nuclei, however, store the memory of strength that is required. This means that if and when you resume your training, as long as you are giving your body the nutrients it needs, you should be able to regain that strength and mass in a much shorter period of time.
This is assuming that there wasn’t a specific physical condition that caused you to atrophy in the first place.
Muscle Memory and Steroid Use
Another interesting discovery about muscle memory is the effect that anabolic-androgenic steroids have on it.
Steroids have been shown to increase the number of myonuclei in muscle. This leads to increased capacity for muscle protein synthesis and increased hypertrophy as a result.
A 2013 study using mice found that subjecting them to anabolic steroids (and exercise) increased myonuclei and increased muscular hypertrophy.
After the steroids were taken away, and exercise ceased. The muscles hypertrophied back to regular size.
Then after 3 months of non-training exercising was resumed. The mice that had taken the steroids produced huge gains in hypertrophy over the next 6 weeks, whilst the group who had not taken steroids saw much less significant gains .
So now we have an idea why bodybuilders (who are the most likely to be experimenting with steroids) were the first to report muscle memory.
We also have a possible explanation as to why it has taken so long for research to find any evidence. If they were using non-steroid taking subjects there might not have been any.
As mentioned at the beginning of the article there is a debate as to whether muscle memory exists.
Whilst there have been some well-received studies that support the theory, there have been other studies that could not find any evidence of myonuclei surviving the non-training atrophy of muscle.
Yes, muscles do have memory. Not the kind of memory that we store within our brains. But a special kind of memory that is unique to the myocytes, or muscle fibres themselves.
If you have trained long and hard in the past and managed to bulk up and strengthen your muscles, then you should be able to achieve this same strength and form again. And perhaps slightly quicker than you did the first time around.
What cannot be denied is that training after a long layoff can produce results a lot faster than training for the first time.
Whether this is due to the Central Nervous System or whether it is to do with muscle memory is not important to you. So just enjoy the perks!