Physical activity and neuromuscular variables at first measurement.

Values are mean(SD). The first test of physical activity, countermovement jump and single-leg hopping were conducted before isolation. Grip force was first measured on the 21st day of isolation. g = 9.81 m/s2. Activity temperature is a measure of the average absolute acceleration over the course of the day: more changes in body position (e.g. sit-stand) and more changes in walking speed means higher overall average acceleration.