On the reverse side, I've always wondered if being in a weightless environment makes your muscles feel great[0], since they aren't working against gravity. Over the years, gravity can create lots of problems for posture, which is why swimming (which lessen the effects of gravity) feels great.

[0] I'm using "Feel" in a relative context, since muscle weakness/wasting will not feel good once you're back in a non-weightless environment.