I own a 13 year old black lab who is continuing to lose muscle in his hind area. He grunts when he lays down and gets up. He was diagnosed with hip displaysia at 2 yrs old. I can hear his joints crack as he walks. He still wags his tail and has a healthy appetite. He sleeps most of the day. He is starting to fall now and I told the vet I didn't want him in any pain. He gets pain medicine 2 x per day. Periodically he will pick up his toys and play with them but that is now far and few between. I'm in the process of moving and my new house will have steps () and tile floors (). I'll get non skid throw rugs for the tile but I want to build a pool and on a daily basis take him in the pool. Will that help him? Do I let him swim in the pool or just hold him to help the pain?
Hydrotherapy can be a great way to help ease the stiffness in old joints as thy are still being used but it is a non weight bearing exercise so will be less painful. You need to make sure the water is warm - like a nice warm bath to ease sore muscles. Cold water will not help and could worsen some conditions.
Let him swim around but be sure to supervise as swimming uses a lot more energy a lot quicker than going walkies so you need to be there to help him out of the pool when he's done. If it were me is be in the pool with my dog as I think it would be great fun to swim together!
You might want to get him a life jacket since his back end is weak. My boy couldn't hold his rear end up in the water once his back end started weakening.
We had a dog with rear leg wasting. Swimming might be good, but it might not cure anything. Steps and tile are not good though, so hopefully you can work around those things. Try looking into laser therapy. That helped us for awhile.