Because I was eating lighter and hadn’t been laid up once by injury, I was able to run more; because I was running more, I was sleeping great, feeling relaxed, and watching my resting heart rate drop. My personality had even changed: The grouchiness and temper I’d considered part of my Irish-Italian DNA had ebbed so much that my wife remarked, “Hey if this comes from ultrarunning, I’ll tie your shoes for you.” I knew aerobic exercise was a powerful antidepressant, but I hadn’t realized it could be so profoundly mood stabilizing and—I hate to use the word—meditative.
