I had both hips replaced at age 54. Beware of running on paved roads and concrete. They will wear your body out way early. Tracks, beaches, stadiums, GOOD SHOES, dirt trails are much better for your joints.

Hiking and long walks are excellent cross training with biking. Take a good joint supplement as well.

20 years ago I was able to ride a bike for a year while putting off knee surgery (meniscus tear, bucket handle). I couldn't do much anything else, but i could ride. Biking is amazing.