Lots of guys do yoga, but still more women go to the classes. I do yoga at home and at studios. I've been doing yoga for about 10 years. The fact is I'm usually one of the 10 percent or so of men in any yoga class I attend.

The field of personal training is expanding at about the same rate as American waistlines. Obesity is a serious and growing problem among average Americans. As medical research links more health risks, like heart disease, hypertension and stroke to even moderate obesity, more Americans are trying to improve their health by getting fit. Some companies have even opened employee fitness centers in an effort to improve their employees' health and reduce the cost of health insurance.