SEMPER FI HIGH: Sometimes walking gets you there faster than running. This insight came to me on Saturday as I was making my way up a steep mountain trail with some 400 other sweating, hard-breathing athletes in the Toiyabe National Forest of eastern California. We had come to the Marine Warfare Training Center to run a 10 kilometer (6.1 miles) race that began at 6,800 feet above sea level and gained 1,000 feet in the first mile, a stretch known affectionately to local Marines as Heart Attack Hill. The idea that running can be slower than walking is counterintuitive, until you figure out that at a certain level of steepness people who are taking long walking strides are moving up the hill faster than people taking shorter running steps up and down. "Established in 1951 specifically to provide mountain and cold weather training for replacement personnel bound for Korea, this intense training ground is one of the Corps’ most remote and isolated posts, and one of its most difficult training grounds." No kidding. Obstacles on the Marine Warfare Training Center included tire course, low crawl, five-foot wall climb, and tunnel crawl. I arrived 36 hours prior to race time, hoping to get at least somewhat used to the high altitude before deciding to run at race speed straight up a hill, sucking air much thinner than most of us were used to. The last mile of the race was blessedly downhill, and exhilarating in ways that I won't even try to describe. I was the 166th contestant to cross at finish line, at 1:08:21. Injury free, and no post-race pain that a couple of Tylenols couldn't handle. But the biggest high was the opportunity to spend a day with some of the bravest, most fit, most dedicated young men and women you'll ever hope to meet. Here's to every member of America's armed forces and the spectacular work they do to keep our nation free.