@twocents: Correct. That is why I walk, and do not use the bicycle, or any other machine at my gym other than walking. Of course I do weights also, especially for my legs. I also find that most pools, other than outdoor pools, smell strongly like the chemicals they put in the pool. Having had several outdoor pools, I know not only chlorine is added, but also muriatic acid, that can cause damage your eyes, nose, throat and lungs if fumes are inhaled. Already having asthma, I prefer to be in an environment that does not risk breathing potentially toxic fumes. My "bronchials" get tight any time I walk into a enclosed pool.

@swim4ever, This just in. Swimming sure can't hurt.
https://www.betterbones.com/exercise/water-exercise-and-swimming-builds-bone/?goal=0_0ba60a2aed-b0f29130c9-444714216&mc_cid=b0f29130c9&mc_eid=0820a588d4