I had a brain bleed three years ago and in my case heavy arm or leg comes and goes. I try to maintain arm flexability and strength with 8lb dumbells, core strength with modified planks , and overall balance and endurance with walking and (sort of) jogging. Every thing you do is PT - even shoes with laces. Don't give up on what you can do! Talkto your neurologist or PT. You are not alone.