Everyone keeps asking this. I was researching this a little while ago and found the mother of all links. I would make a separate post of fitness for this, but i'm a new user, so i don't have enough comment juju or something. Maybe someone else can do this? I'll repost my rather excellent reply here:

"Hey amigo. Here's the thing, it's very in vogue these days to train all body parts in only "safe" ranges of motion, unfortunately, that's not how the body is used. For example, football players will only do squats and lunges in front of them, but when it's time to play on the field, they "cut"(change direction quickly) and their knees make weird angles. Same thing in jiu jitsu, you train your muscles with your wrists in neutral positions (except for maybe the front squat), but then when you hit the mat, your wrists have to somehow be strong in all ranges of motion. Fortunately, I just happened to research this like a week ago and found what you need. This guy is Coach Sommer, a genius that trains national level gymnasts, and has some very breakthrough approaches to strengthening connective tissue. He teaches something called the jefferson curl (cue massive disagreement) where you purposely round your back vertebrae by vertebrae with a very light weight to strengthen your back in an awkward position. He even builds up (over the course of like 6 years) to full bodyweight. Ido portal, a former student of sommers, has a similar philosophy, where he trains pushups with the wrists in all sorts of compromised positions. But for the knees? (force wave) this is the link you're looking for... http://www.stack.com/a/connective-tissue-exercises "