Probably you've often wondered what will happen to your hard-earned muscles when there is an unexpected break from training - resulting from the plethora of duties, trip or injury. Does our body can make up for losses faster after returning to the training regime? Will we regain lost muscles much faster than you can build your muscles in the first place?

Muscle memory in practice

Colloquially speaking, muscles have "memory" - muscular tissue, which over a period of time was exposed to training stimuli, after a longer break from physical activity responds better to return to training, compared to the muscles of untrained people. Muscle memory means that we notice much faster return to form after months or even years of inactivity than people starting training from scratch.

Of course, this is a process and the first training days after a longer break will be a big burden on the body, which will result in painful muscle sores. However, after a short time you can observe a faster training progress in relation to people who are just starting their adventure with the gym. Certainly, these discrepancies result not only from the muscle memory itself, but also from differences in the level of knowledge and training experience.

Muscle memory - mechanisms responsible for this phenomenon

Muscle cells (myocytes) can successively increase in size as a result of training stimuli, as well as the adequate availability of nutrients. During growth processes in the muscle cells, the number of cell nuclei increases, which enables more efficient production of muscle proteins. In short - myocytes with more cell nuclei grow faster.

When we stop exercising, our body begins to get rid of muscle mass, because it is unnecessary energy load. During this time, muscle proteins are broken down into amino acids, which then the body uses for the synthesis of other proteins needed during this period - such as hormones or enzymes. However, this process is not accompanied by a reduction in the number of cell nuclei. Therefore, myocytes shrink, maintaining their ability to develop rapidly, conditioned by the presence of cell nuclei!

Research confirms that muscles subjected to training stimuli in the first phase increase the number of cell nuclei, followed by intensified protein synthesis. At the time of reduction of the intensity of training stimuli, there is a progressive reduction of musculature, while maintaining the number of cell nuclei. This phenomenon is responsible for the occurrence of muscle memory.

Leave from the gym - should you be afraid of muscles?

You should absolutely not think in terms that you will lose all the muscle mass you have developed, and you will have to start over again because you have an unplanned break from activity. Depending on the training experience, you need between 2-4 weeks to note the reduction in muscle size and strength. However, a return to form should take place over several training sessions.

Of course, returning to the form from before the break, will largely depend on the length of vacation, as well as the reason for rest - the case looks different in the event of holidays and injuries. The muscles that you lose during this time will rebuild sooner or later after returning to the activity, because as has been mentioned earlier, your cell nuclei are not going anywhere.

However, during the free time of training, try to maintain physical activity in activities other than lifting weights, for example by walking. Keeping active will help you lose less muscle, strength and increase your overall ability to work, while increasing your reaction time to strength training. Do not use time off from training as an excuse to be lazy.

Progressive muscle overload is crucial for long-term increases in strength and size of muscles. However, it is logical that you are unable to progress indefinitely. A break in training and taking the time to re-sensitize the muscles to exercise stimuli can give more benefits than underestimating the long-lasting feeling of overtraining. Probably the training "reset" will help you develop more after the break.


Based on available research, the phenomenon of muscle memory actually exists. When you stop training, you lose muscle mass to lower metabolic costs, but the cell nuclei remain in myocytes, so you can quickly regain all your muscle mass. Even after a long break, the muscles of the trained people respond better to the effort than the untrained people.