My Legs Have Gotten Weak From Being In Bed 2

my legs have gotten weak from being in bed 2 mo.'s with flu now very hard to walk I had polio when I was 9 and was paralyzed but recovered quite well after 2 yrs of therapy. now I am 70 and also have arthritis in that weaker leg how can I strengthen them need cane now. YYYY@YYYY thank you