Exercise makes an amazing difference. I began a marathon training program six month ago, and it has dramatically impacted my energy level. I haven't gotten sha

Exercise makes an amazing difference. I began a marathon training program six month ago, and it has dramatically impacted my energy level. I haven't gotten sharper in the past six months, but I'm more robust to energy-sapping conditions. An occasional bad night of sleep doesn't ruin my work day. I have a lesser mental block when starting big projects. I'm not worn out after a long work day, so I've worked more on pet projects without sacrificing time with my girlfriend. I have a major incentive to eat light, since nothing is worse than a hard run with a stomach full of grease. As a plus, I now understand the value of working incrementally towards a large goal. I didn't find it difficult to work into my schedule. My highest-mileage week only took six hours of my time, and most weeks were less than four hours.