all the complexes have a gym, Vista being the most basic, and Patterson being the highest quality.
I called the housing office, and they said the Vista gym has things like treadmills and dumbbells and something to exercise you back and legs etc. They weren't exactly positive if there was more in there though.
Patterson's is apparently state-of-the-art. So if you are a real gym enthusiast then the trip to Patterson might be your best bet, but Vista still has one available if you don't want to make the trip.