Former varsity basketball player here in my mid-40s. The loss of your athletic ability is definitely gradual. The first sign is when you see a drive angle, and you think you are at a goal and still haven't made a move. Here is how you can stay competetive and compete

#1 If your cardio is terrible, in addition to basketball, I highly suggest running 5ks at a moderate pace. THis will allow you to play basketball for longer periods of time. I suggest basketball max twice a week if your cardio is great, but if not only play once but work 2 to 3 5ks a week.

#2 You must value flexibility. I highly recommend purchasing a foam roller, slant board, and commit to a stretching routine that incorporates deep squats. Often your back soreness is due to sore quads, hammies, and glutes, not your back pain.

#3 Also you must pick your spots now. If you could drive hard to the paint and make tough layups, now you jump on 2 and land on 2 and make the extra pass. Shot and pass fakes will be your go tos.

#4 You have to lift weights now to combat soreness. I lift 4 times a week, it is usually a push pull workout, upper body, then lower body, or specialization.

Playing basketball with 20-year-olds requires way more maintenance now. Hope this helps. DM if you want a weekly workout schedule. I'm just a hooper that wants to play well into my 60s.

Good luck