Most buildings in Dubai Marina have a pool and a gym, but the standard can vary a lot, so the facilities are something that you really want to consider, when choosing which building to live in. Sometimes it can pay off to spend a little extra on rent to live in a building with good facilities instead of having to purchase pool access and gym membership externally. In our new building the pool area is really nice, so we have not been to the beach club since we moved in.
Trine is visiting right now, and she is at the pool every day. When I go to the pool it is usually just to swim, and when I am done swimming, I go back up immediately. However, Trine brings her knitting to the pool, and she stays there for hours, so by now, she knows our new neighbors a lot better than I do, and the pool staff all recognize her, so she does not even have to sign in anymore:)
Our building also has a very nice gym, and I try to go to the gym every day. These days I am working really long hours on my online shop, and I feel that going to the gym, gives me the energy I need to stay focused. I usually do really short sessions, and I only rarely spend more than 30 minutes in the gym, but this is what works for me.