“Don't worry! If you stop working out for a while, your gains won’t just go away – and even if they do, they won’t take nearly as long to get back as they took to get the first time.”
If you’ve ever had an injury or otherwise been forced to take a break from the gym, it’s likely you’ve heard someone say something to that effect. But is it true?
This encouraging idea is based on the theory of “muscle memory”. Essentially, muscle memory is the belief that muscles store a blueprint of the progress they’ve made, allowing you to make similar (or greater) progress much faster the second time around.
While the idea has been supported by bro-science and anecdotal experiences, quality research on muscle memory has been lacking. Until now.
Researchers at the University of Oslo in Norway have demonstrated conclusively that muscle undergoes permanent changes in response to weight training.
They did an experiment that found the number of myonuclei (foundations for muscle fibers critical to increasing their size and strength) increases in a muscle when it grows. Even after many years, the number of myonuclei remains elevated, even if the muscle fibers shrink to their original size. Put simply, your muscles really do hang onto the blueprints of the gains you’ve made.
In the diagram that follows, the myonuclei are represented by the black dots – note how even as the atrophied muscle fiber has shrunk (bottom right), the amount of myonuclei remains higher than before training (bottom left).
Because the myonuclei increase remains even after long periods of inactivity, the fibers maintain the ability to grow more rapidly than they did in their original state. Muscle memory is for real.
For anyone considering getting back into lifting or recovering from an injury, the confirmation that muscle memory is legit is huge. Not only can size and strength gains be restored; progress can be made two to three times more quickly than it was in the first place.
If you’ve been forced out of the gym for a while, and you’ve been frustrated at how much seems lost, consider yourself on notice. You did it once, and you can do it again – and the gains will come even faster. No excuses!
Tip: Try the at-home Leg Day exercise that’s so good you’ll do it even when the gym opens up.