Injury is our body's way of telling us that we're pushing it too hard so you couldn't say we're not trying!!!
I've got an injury that keeps playing me about but luckilly its not in my lower body. I have whats called an impinged ligament in my shoulder. Caused by bench pressing apparently. I'm trying to go up a weight cos for my 2nd dan I have some bare knuckle, full contact to do and I know my opponent is heavier than me. Though having said that its not all muscle on his part!! Its just needs rest but we all hate resting injuries don't we?!!
Got to go to work now though, going to get some training in before I start.
Train hard and act as if you like it!