They say that exercise is often easier when you do it with friends. Well, since I began this regimen I've had the constant company of two new riding partners: disappointment and pain . The first one shows up bright and early every morning when I get on the scale. In spite of my seemingly endless hours on the treadmill over the past three weeks, the numbers are agonizingly slow to change. And while I am well aware that the daily weighings are only meant as reinforcement of my goal, I can't help but feel a bit downtrodden when I come face to face with the snail's pace of my progress (which, on some days, is measured in negative numbers). My other new buddy is with me day and night, distracting me from work and tormenting me in my sleep. Every joint in my body feels like it's filled with broken glass. My muscles throb and spasm. My body doesn't like exercise, it wants to remain still and sofa-bound, and the o...