Updates from the YMCA...Great Mysteries

I am on week 4 of working out in the weight training section of the YMCA. I am amazed at the differences I am feeling now that I've added weight training to my regimen. The biggest thing is the increase in confidence. I felt really good about my time on the treadmill or the eliptical machine but the weight training boosts me up everytime I achieve a new weight. Oh, and my jeans are talking to me. Yeah! Anyway, I have experienced two great mysteries that pertain to the weight room. I am going to put these questions out there and hope I can get some responses.

1) Why do men walk around like peacocks when they are in the weight room?

2) Why do men have to grunt when they are lifting the weights? (There are some women at my YMCA who lift some pretty heavy weights and they NEVER grunt.)

Anybody have any ideas about these mysteries??