Muscles May Preserve A Shortcut To Restore Lost Strength

"Can muscles remember their younger, fitter selves?"

"Muscle physiology lore has long held that it is easier to regain muscle mass in once-fit muscles than build it anew, especially as we age. But scientists haven't been able to pin down how that would actually work."

"A growing body of research reviewed Friday in the journal Frontiers in Physiologysuggests that muscle nuclei — the factories that power new muscle growth — may be the answer. Rather than dying as muscles lose mass, nuclei added during muscle growth persist and could give older muscles an edge in regaining fitness later on, new research suggests."

This work could affect public health policy and anti-doping efforts in sports, says Lawrence Schwartz, a biologist at the University of Massachusetts, Amherst who wrote the review. But some scientists caution against extrapolating too far from these studies into humans while conflicting evidence exists.

"One thing is for sure: Muscles need to be versatile to meet animals' needs to move. Muscle cells can be sculpted into many forms and can stretch to volumes 100,000 times larger than a normal cell. Muscle cells gain this flexibility by breaking the biological norm of one nucleus to a cell; some muscle cells house thousands of nuclei."