SuperFan
Fapstronaut
knees and running......
Understood. Well, only you really know what's going to be good for you and what isn't. If your knees are giving you trouble, you can definitely ease up when it comes to stuff like squats. You can reduce the weight so you're building up your knee strength.
As far as running goes, maybe there's a lower-impact exercise you can do for cardio. A popular one these days is 30 minutes of walking on a treadmill at 3mph with a 12-degree incline. Very low impact on the knees. And if you have access to a pool, it's hard to beat swimming!