I had to work up to 200 JJs. My knees couldn't take it either, and I baby my knees so I would stop as soon as they felt tired. But, eventually I just kept going and it's fine. I'm working up to 6 minutes on the jump rope. Cardio wise I can do it, but the knees and lower legs get tired and I start to make mistakes which lead to tweaks in this or that ligament or tendon, and soreness. So I'm working up slowly.

My knees are better off when I use them, even the jumping and etc. I just don't do too much.

Karen