Work

Responses of Muscle Volume, Strength, and Motor Unit Properties to Bed Rest and Retraining in Young Males and Females

Year: 2026

Type: preprint

Abstract: Sex differences in motor unit (MU) properties to simulated microgravity are unknown. Young males and females completed a 21-day head-down bed rest followed by a 21-day retraining. Bed rest reduced knee extensor strength and volume without sex differences. MU firing rate decreased in both groups, more in females, alongside increased serum C-terminal agrin fragment. After retraining, these measures returned to baseline, whereas strength only partially recovered, remaining below baseline.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.11.04.764387