I’m 67, had my first knee replaced in April, back in my office 4 days later doing 6 hrs a day. Did PT 3 times a week for 5 weeks, by 8 weeks I was riding my bike 30-40 miles 5 x’s a week. Had my other replaced 8 weeks ago (6 months after the first) followed same routine and back riding. I had minor muscle pain as expected and Tylenol took care of that. By 6 weeks off of Tylenol. Range of motion before surgery was 120, first knee is 110 and the second knee is 115. PT said recovery regarding range of motion could increase up to one year providing one stays active with the excercises. Great not to have pain when I walk! Keep up the therapy.