Hi Mt. Sgt,
I think you go out and do what makes you happy.
Walking in a pool to me is like driving 20mph on the autobahn lol
I've been lifting weights off and on ever since high school and I'm 38 now. I find excercises that feel good and some that irritate it and mold my workouts around what doesn't irritate the joints. Chest workouts seem to be ok for me but back workouts can irritate my joints later.
Leg workouts I can do just about anything but squats. Any weight bearing on the spine I try to avoid. I do lay down squats to replace the upright squats and that is plenty enough for me.
I have a great way of swimming. I had tried swimming many times and was discouraged because I have neck involvement and I spent too much energy lifting my head out of the water every nanasecond because I also have no chest expansion.
At any rate I got a SNORKEL
best thing I purchased for excercise. I can swim and breath at nanosecond speed and just swim! Really good excercise to compliment your excercising.
I also find low impact, high intensity cardio to get the heart rate up. My favorite for two things is the Step Up machines. I sweat within 8 minutes of being on it and my back doesn't get bothered one way or another by it. Great leg workout. Two I'm training for a summit to Mt. Ranier. The only thing that could be a factor for me is the chest expansion after 10,000 ft. I need AIR lol
Have a good day,
Tim