very hard on your body. If you keep playing eventually you will go down. I love basketball, I played it multiple times each week until I was 39. That's when basketball destroyed one of my legs. Now I coach basketball, and I work out in a way that doesn't destroy my body. It's not just your knees, it's your lower back, your ankles, tendon/ligaments. I even dislocated my shoulder and tore my labrum playing basketball. It is just hard on the body. I still love it.