Lets 'Do' it Right: Exercise.Wendi Thomasgomemphis.comMore than 60 percent of black women are overweight. And I'd bet that many of these women have nicely styled hair. How are the two related? Many of us are overweight because we don't exercise. And I maintain many of us don't exercise because we don't want to sweat out our hair. For those unfamiliar with black hair, here's a primer. Many black women have their hair chemically treated to make it straighter. As the hair grows, the process - called relaxing - must be repeated on the kinkier roots.Water, humidity and sweat are the...