In Encounter At Farpoint they make reference to a zero gravity gym which we never see.
And I'm not sure how a zero gravity gym would work anyway. You wouldn't get any exercise because you wouldn't be pushing against any resistance. For recreation, it would be very dangerous especially for kids, a lot of banged heads. The only possible use I can see for a zero gravity gym is low impact recovery for distance runners, where it would be an improvement over those pricey underwater treadmills they use today.
Though I imagine athletes in the 24th century might have greater use for increased gravity training than reduced gravity training, the same way they do high altitude training today.
And I'm not sure how a zero gravity gym would work anyway. You wouldn't get any exercise because you wouldn't be pushing against any resistance. For recreation, it would be very dangerous especially for kids, a lot of banged heads. The only possible use I can see for a zero gravity gym is low impact recovery for distance runners, where it would be an improvement over those pricey underwater treadmills they use today.
Though I imagine athletes in the 24th century might have greater use for increased gravity training than reduced gravity training, the same way they do high altitude training today.