Muscle Memory: How Does It Work?

Two types of muscle memory

In colloquial terms, muscle memory is the ability to perform certain movements automatically. These actions are so deeply ingrained in our habits that we don’t even need to think about them. However, this is an oversimplification linked to the outdated stereotype that ‘a lot of muscle means not enough brain,’ which, thankfully, is becoming increasingly rare. This is because muscle memory actually operates on two levels: not only as a mechanism without which our daily life would be extremely difficult, but it also as evidence that the benefits of physical activity extend beyond just the muscles.

The colloquial understanding of muscle memory is closer to motor memory, also known as body memory, which involves learning tasks such as riding a bicycle, maintaining correct posture, typing, or playing musical instruments. Our body and nervous system learn certain movement patterns, whether consciously or unconsciously, so that after enough repetitions, we can perform them with less energy expenditure.
This type of muscle memory is procedural memory, where the brain’s neural networks play a central role. The brain memorises sequences of signals received from muscle receptors and associates them with specific types of movements. The automaticity of this muscle memory extends to other cognitive centres, allowing us to perform much more complex tasks and enjoy a variety of effects.

But it turns out that muscle memory is also our body’s unique ability to ‘remember itself.’ It works at the cellular level, more specifically, in the nuclei of our muscle cells. When we train our muscles, they are exposed to stimuli that force them to ‘learn’ how to manage their cells in a specific manner. This results in an increase in cell size, requiring appropriate proteins as building blocks and more energy from the mitochondria.

Additional cell nuclei are then needed to manage and process the information necessary for the proper development and function of muscle cells. And the body produces more nuclei in response to our training progress. This type of memory acts as a sort of ‘backup’ of information about our muscles and is crucial when we take a longer break from training.

Muscle memory and resuming workouts

When we stop physical activity for an extended period, our body reduces the muscle tissue it no longer needs, as maintaining it would require too much energy. Muscle fibre volume decreases, as does the number of active mitochondria that previously supplied energy during exercise. Muscles become smaller, weaker, and less resilient after just a few weeks of inactivity. However, the cell nuclei formed as a result of training do not disappear!

At the cellular level, our body ‘remembers’ what it was capable of and how to respond when the training stimulus returns. This means that regaining your previous fitness level, even after a long break, is much easier than starting from scratch. Even if we don’t exercise for a long time, with a solid foundation of prior training, we can achieve a satisfactory level of fitness relatively quickly.

Motor memory also plays a crucial role in getting back into shape. A well-trained nervous system makes it relatively easy to do exercises even many years later. Procedural memory stores the correct technique for movement patterns, making training more effective. While weakened muscles won’t immediately handle maximum loads, the combination of strength, motor memory, and muscle memory within the cell nuclei will accelerate progress for those who resume training.

How to develop muscle memory?

The muscle memory stored in the nuclei of muscle cells can remain intact for up to 15 years. Although it is difficult to lose, it is not impossible. The risk comes from central nervous system diseases (Alzheimer’s, Parkinson’s, Huntington’s disease), strokes and myopathies, or neuromuscular disorders. However, muscle memory can be supported at both the muscular and motor levels. We have some tips for you.

1. Practice and repeat. More repetitions improve the motor memory. And the better the motor memory, the more effective the training. But pay attention to your technique – bad habits are also reinforced through repetition!
2. Provide yourself with new stimuli. New movement patterns, varying weights, number of repetitions, session times... all of these factors develop not only the muscles but also the nervous system.
3. Focus. A good workout involves more than just repetitive movements; it also requires the right level of focus and awareness of your own body. Avoid distractions, concentrate on your movements, and pay attention to the details.
4. Exercise step by step. In any physical activity, movements consist of several consecutive phases. Taking the time to break down the exercise and concentrate on its individual elements will enhance your muscle memory to remember the details!
5. Be consistent and forbearing. If you are resuming training after a long break, it’s important to be systematic. However, your body needs some time to fully utilise its muscle memory resources. Don’t rush for results; increase the effort gradually according to your capabilities, and the effects will come sooner rather than later.

_References:

1. _{Schwartz L. M., Skeletal Muscles Do Not Undergo Apoptosis During Either Atrophy or Programmed Cell Death-Revisiting the Myonuclear Domain Hypothesis, Frontiers in Physiology, 2019.}
2. _{Lee H., Kim K., Kim B. i inni, A cellular mechanism of muscle memory facilitates mitochondrial remodeling following resistance training, The Journal of Physiology, 2018.}
3. _{Snijders T., Aussieker T., Holwerda A. i inni, The concept of skeletal muscle memory: Evidence from animal and human studies, Acta Physiologica (Oxford), 2020.}
4. _{Gundersen K., Muscle memory and a new cellular model for muscle atrophy and hypertrophy, The Journal of Experimental Biology, 2016.}
5. _{https://www.cambridge.org/core/books/abs/thinking-through-the-body/muscle-memory-and-the-somaesthetic-pathologies-of-everyday-life/6EA9D2B4733A8E9CA63AFEC104432C83, dostęp: 15.07.2024.}
6. _{https://scopeblog.stanford.edu/2022/07/15/the-science-behind-muscle-memory/, dostęp: 15.07.2024.}