The Muscle Memory Debate Finally Solved!

“Use it or lose it” vs muscle memory, what happens to our muscle if we stop resistance training?

Now exercise physiologists do agree that muscle memory is real, but the question is how are these ‘muscle memories’ stored when our muscles seem to shrink with inactivity?

According to a scientific review published in Frontiers in Physiologyfound that although our muscle cells shrink due to disuse, the nuclei gained during resistance training remains. Meaning that when we are young we are able to store muscle nuclei to prevent fragility in old age, but it also means that steroid use in competitive sport has long term benefits years after the crime was committed.

“But by far our biggest cells — are our muscles,” says Lawrence Schwartz, Professor of Biology at the University of Massachusetts. “Muscle growth is accompanied by the addition of new nuclei from stem cells to help meet the enhanced synthetic demands of larger muscle cells,” explains Schwartz. “This led to the assumption that a given nucleus controls a defined volume of cytoplasm — so that when a muscle shrinks or ‘atrophies’ due to disuse or disease, the number of myonuclei decreases.”

New evidence paints a new picture for muscle neclei. “Two independent studies — one in rodents and the other in insects — have demonstrated that nuclei are not lost from atrophying muscle fibers, and even remain after muscle death has been initiated.”

This maens that when a nucleus has been acquired by a muscle fiber, it belongs to the muscle, most probably for life.

“It is well documented in the field of exercise physiology that it is far easier to reacquire a certain level of muscle fitness through exercise than it was to achieve it the first place, even if there has been a long intervening period of detraining. In other words, the phrase “use it or lose it” is might be more accurately articulated as ‘use it or lose it, until you work at it again’.”

“Anabolic steroids produce a permanent increase in users’ capacity for muscle development. In keeping with this, studies show that mice given testosterone acquire new myonuclei that persist long after the steroid use ends.” This suggests that drug free sports should enforce permanent bans for proven steroid cheats, to ensure fair competition.

Reference for ‘The Muscle Memory Debate Finally Solved’:

1. Lawrence M. Schwartz. Skeletal Muscles Do Not Undergo Apoptosis During Either Atrophy or Programmed Cell Death-Revisiting the Myonuclear Domain Hypothesis. Frontiers in Physiology, 2019; 9 DOI: 10.3389/fphys.2018.01887