Our memory is a treasure trove of the mind, acting as a repository of knowledge and a storehouse of life’s moments.
While the brain doesn’t always retain all information, such as addresses or bank account numbers, there are some things it never forgets, even decades later.
How-to motor skills and movement patterns like riding a bicycle, swimming, playing an instrument or typing fall into this broad category.
Neurologists refer to this as procedural memory, a type of unconscious, long-term memory where individuals can recollect how to do something without having to think.
It’s not clear why procedural memories are harder to forget than others, but it might have something to do with where they’re stored in the brain.
This particular area seems to be relatively protected and resistant to rewiring.
A term commonly used in the fitness world is muscle memory – a subset of procedural memory, where muscles can regain strength and size faster after a period of inactivity.
We often think that it’s the brain that memorises how to perform a motor skill because we have repeatedly done it, but researchers have recently discovered a more literal type of muscle memory called epigenetic memory.
This takes place in the muscles themselves, especially when they’re exposed to strength or resistance training.
Basically, your muscles’ DNA (deoxyribonucleic acid) can get rewired in response to what you throw at them, priming the tissue for future gains.
It is as if the muscles remember how strong they were previously and find it easier to return to that level.
Apparently, this memory from past training sessions can be stored on a molecular level for up to a few months, which explains why you can regain your muscle strength (and maybe size) quickly after a break from the gym, compared to when you first started training.
Getting fit again quicker
Lifting weights (or any kind of strength training) give you more benefits than just weight loss and a physically toned or sculpted appearance.
It actually alters the physiology of your muscles; you improve your neuromuscular efficiency and strengthen that brain and body connection.
You create new neural pathways within your central nervous system when you lift weights to build muscles.
When you return to the same activity after some time off – perhaps due to travel, injury or other commitments – these pathways help you relearn these movements faster than when you first created them.
You’re not forming new pathways again, but reactivating old ones that you’ve already created, even though they’ve been dormant for a while – and that’s what muscle memory is all about.
In one 2025 study by the University of Jyväskylä’s Faculty of Sport and Health Sciences in Finland, researchers investigated the quantities of thousands of muscle proteins and found a possible new explanation for muscle memory.
In the study, participants comprising 116 young adult and middle-aged Finnish men and women who were physically quite active, but had no previous experience of systematic resistance training, were put through 10 weeks of resistance training, followed by a 10-week break, then another 10 weeks of resistance training.
Published in The Journal of Physiology, the results revealed that muscles “remember” training at the protein level and the memory trace of previous resistance training persists in muscle proteins for over two months.
No one knows for sure how long muscle memory can last; studies say it ranges from a few months to 15 years, and possibly, even permanently.
However, the general consensus in the scientific community is that muscle memory does last for at least a few months.
Start young
Now, just because your muscles have memory doesn’t mean you should go easy on your strength training routine.
Taking two or three weeks off for a holiday will not make a noticeable difference in your muscle size, but you may notice a slight drop in muscle strength.
Most people assume that if their muscle size is smaller from not training, they’ve lost muscle mass, but this is not the case.
It’s due to the decreased water retention and glycogen stores in the muscles that make it seem as though you’ve lost muscle size fast.
Your genes, age and activity levels factor in as well – the more muscles you have and the younger you are, the faster you can regain the size from returning to training.
One 2019 study published in the Journal of Strength and Conditioning Research showed that after four weeks of detraining, children between the ages of 10 and 13 were able to maintain their muscles.
The younger you are, the better your body is at maintaining muscle mass without training for long durations.
Ageing does have its setbacks, as it is harder to gain muscles as you get older.
Hence, starting early is ideal, as you’ll find it easier to build muscle and reap more benefits of muscle memory in the future.
While muscle memory is a great tool to develop, it has its limitations, i.e. the longer you take a break from workouts, the longer it’ll take to return to your original fitness level.
In addition, muscle memory is also specific to a certain movement so if you’ve always done squats to strengthen your quadricep muscles in your previous workout, then after a break, switch to cycling at a high intensity to work this same muscle group, your muscles are unlikely to be able to take advantage of the memory from squatting.
Understanding how muscle memory works can help you improve your fitness and make it easier to return to exercise after a hiatus.
Revathi Murugappan is a certified fitness trainer who tries to battle gravity and continues to dance to express herself artistically and nourish her soul. For more information, email starhealth@thestar.com.my. The information contained in this column is for general educational purposes only. Neither The Star nor the author gives any warranty on accuracy, completeness, functionality, usefulness or other assurances as to such information. The Star and the author disclaim all responsibility for any losses, damage to property or personal injury suffered directly or indirectly from reliance on such information.
