The number one thing I have been taught, and learned over time,, is form in the most important thing to know when working with weights. Our joints and tendons and muscles are meant to work in certain ways, and if we put the wrong amount of stress or weight on them ,, it could be bad. Now Im not saying that lifting heavy is bad.. You guys should know me by now.. I love lifting heavy.. I actually got a personal record on the leg press last week! Very exciting! But I did not bounce the weight off my feet, I slowly lowered and pressed,, and I had a spotter, in case i couldnt press it up..
I just want everyone to be safe, and be aware that there is a proper form for every excercise. If you are questionable about something ,don't do it until you are sure of the proper form. It is not worth being injured, just to show up someone else in the gym. Or to impress the other guys in the gym.
Happy Lifting! :)