Most men fasten their belts below their waists. It’s just another way of avoiding the truth about that gut. Grab a tape measure and put it around your body at the level of your belly button. That number should be less than half your height. So for my 6’1″ frame, I need to keep my waist under 36.5″. If avoiding heart attacks and diabetes isn’t enough motivation to eliminate that gut, consider this: For every point your body mass index is over 25, your testosterone drops 3 percent, which isn’t very manly.