Most people will go over to a bar to do dips (i'm talking about the bars that are parallel to one another that people put either hand on, then bend at the elbow and shoulder as if 'dipping' down towards the floor) and not do the full motion, while at the same jerk their bodies around mightily. A dip is only done properly by a very select few, those who really focus on proper posture for the exercise. If proper posture is not adhered to, an extreme forward head posture can easily occur. Sorry team, but I don't want anyone that reads this to have neck problems ever, especially if we can avoid them in some way. Let's learn the Dip shall we?
Grab handles with each hand on either parallel bar, ensuring that chest is up, shoulders and head are back. Slightly draw in your abdomen and glutes. Start with arms straight, focusing on bringing the elbows back behind you as you begin to descend. Stop once arms are bent 90 degrees at the elbow, making sure that chest is still nice and high with shoulders and head back. Make sure too that wrist is atraight, not bent excessively. Push body back up until arms are fully extended, ensure proper posture, and repeat.
Now, I bet some of you guys are thinking "Hey, I know how to do it, and sometimes i'll put on a weight vest and add more weight to my own body." Umm, I can almost guarantee that, if this is you, you are doing the exercise improperly. I'm sorry, but next time you perform a Dip ask a trainer to watch your posture. Instead of going for extreme weight, why not become a master of your own body and just do your Dips with body-weight, seeing how many you could get? This was you'll be protecting your shoulders and be less likely to hurt yourself, plus you'll look like an animal when you can bust out 10-15 (or even more) solid Dips! Try out this exercise, and it's never a bad idea to ask a professional if you are doing the exercise properly.