How Muscle Memory Can Fast-Track Your Progress
Your muscles can remember strength gains you made months ago—even after you've been inactive. Trigger that memory, here.
Your brain can't always retain certain info, like your credit-card number (likely a good thing) or what happened to your sunglasses (check the top of your head). But you can probably still remember how to ski after years of not hitting the slopes, or how to do a cartwheel even though you haven't done gymnastics since you were a kid.
Your body's ability to pick up where it left off is called muscle memory. But your muscles don't actually memorise anything—your brain memorises how to perform a motor skill. "When you perform a particular movement over and over again, you're training your neuromuscular system until your central nervous system learns to execute that movement as a smooth, coordinated action you don't even have to think about", explains Heather Milton, CSCS, a registered clinical exercise physiologist and supervisor at the NYU Langone Health Sports Performance Center. (Though this isn't a reason to not pay attention to your form, she notes).
While muscle memory as we've known it mainly takes place in your brain, researchers recently discovered a more literal type of muscle memory, called epigenetic memory, which takes place in the muscles themselves when they're exposed to strength training. In this instance, your muscles' DNA can get rewired in response to what you throw at them, priming the tissue for future gains. In fact, a new study published in the journal Medicine & Science in Sports & Exercise found that muscles can actually store memory from past resistance-training sessions on a molecular level for up to 20 weeks. That could help you fast-track your progress even after a (lengthy) hiatus from the gym.
Sounds too good to be true? Get this: In the study, participants strength-trained just one leg three times a week for 10 weeks, then took five full months off from training. The research team found that the leg that had been previously worked was significantly stronger than the untrained leg—so much so that it was able to move weights 10 to 25 percent heavier, says study author Marcus Moberg, an assistant professor at the Swedish School of Sport and Health Sciences in Stockholm. So, if you and lifting are on a break and you can't bear the thought of starting again, remember, you could be up to 25 percent further ahead in your training journey than you were when you first started.
A new study published in the journal Medicine & Science in Sports & Exercise found that muscles can actually store memory from past resistance-training sessions on a molecular level for up to 20 weeks.
Moberg's team also biopsied participants' muscles both right after the 10-week training period and after the final workout five months later. What they found was that there were higher levels of the gene and protein markers believed to be related to muscle health and growth in the trained leg, as well as greater muscular endurance, which could explain its strength.
In that way, it appears that the brain and the muscles work together, Moberg says. Your brain locks down motor skills, while your muscles hang on to structural changes that can help you regain and resurge diminished strength faster.
This news doesn't give you an excuse to put your dumbbells in storage. It's still true that deconditioning can start to occur as early as a few weeks after pausing exercise, though the effects vary, depending mainly on the type of activity and your fitness level before detraining. Most people will lose some aerobic capacity within a week, says Milton, while a decline in strength-training prowess takes longer and affects people differently. But whether you're off your game for a week or five months, know this: "If you've trained in the past, chances are, you did not lose all of those gains", says Milton. "You're now somewhere between your peak fitness and your original baseline". So … it could be worse.
The discovery shouldn't push you to go all out when you return to your fitness routine either. Do yourself a favour and take the first few sessions or weeks slightly easier than you did where you left off. "Even a very well-trained individual will still need to start off at a lower level. They just may be able to ramp up at a faster rate than someone who has a less extensive training background", says Milton. You don't want to start up again only to get sidelined by injury or overtraining.
And while an activity might not feel great or look pretty after a long break (ahem, adult cartwheels), it's motivating to know that it's nearly impossible to truly go back to square one in a matter of months or even years—and you may progress faster than you did the first time around. Just don't forget to thank your brain—and your muscles—for that.