Just being around a running wheel—even if they don’t run—helps male rats handle exercise stress a little better, but not as much as if they were used to using the wheel regularly.

Rats that got used to running on a wheel before a tough workout had lower sugar and stress markers in their blood compared to rats who weren’t used to it — meaning getting used to exercise might help their bodies handle new workouts better.

Rats that slowly get used to running on a wheel over 8 days don’t show signs of stress in their blood — their stress markers either stay the same or go down, suggesting the routine isn’t stressing them out.

Rats that slowly get used to running on wheels can run much longer than rats that don’t, showing that practice helps them handle exercise better.