One out of every two Americans will suffer from some mental disorder during their lifetimes, with depression being the most common problem. How do most of us cope? Usually, we turn to overeating, drinking, and smoking. In short, we treat our unhealthy mental reactions to the American lifestyle with even unhealthier physical habits.Clinical psychologist Keith Johnsgard -- an inveterate runner who is in his 70's -- proposes a better solution in this...