If you watch a little kid try to pick up something heavy usually you will see them holding their breath and scrunching their whole face up. It's a serious business and they are communicating through their actions. Usually they will also take a peek to see who is watching them, and this doesn't really change too much when you go to the gym and watch the adults lifting. I'm often amazed by the people who neglect the advice of the karate master, Mr. Miyagi.
You know Mr. Miyagi, actor Pat Morita (sorry Jackie Chan, but Pat will always be the "real" Mr. Miyagi to most of us.) He was the guy who said to Daniel-San, "Don't forget to breath. Is very important." And this really is a life lesson. Without breathing life would be very short, and withot proper breathing during workouts and cardio, you could very well hurt yourself. Holding your breath during the concentric portion of your lift puts a great deal of stress on your body.
People have been known to get dizzy, have nosebleeds, and in extreme cases brain aneurisms have listed this stressing of the body as a possible cause. So what should you be doing? Anytime you are doing the concentric part of the lift you should be exhaling. The concentric part, for those who may be confused or just want clarification, is when you are tightening muscles. This is when you are pushing up on a bench press or a shoulder press, or pulling on a back exercise. It is also when you are pushing on a leg press or in the 'standing' part of a squat.
The opposite portion of the lift is called the eccentric portion and at that point you should be inhaling. To clarify again, this is when the weight is approaching your body on a bench or shoulder press, or when the weights are moving away from you on a back exercise. This is also the portion when your fanny is heading for the ground on a squat.
Another way to look at this is that you are exhaling when you working and inhale on the release portion. Hopefully this makes it crystal clear.
Don't take your breathing for granted and think about this whenever you are lifting. I will write more on breathing for running and cardio for a future article. As always any question you have, I would be happy to address in future articles as well. Stay healthy and stay happy!