400 meter Walking lunge
Post time and number of steps to comments.
Now for something completely different…
“Humans were just not designed to work for extended periods of time at 80-90% VO2max. Our evolutionary blueprint, the last draft of which was completed well over 10,000 years ago, set us up as great slow-movers and occasional fast sprinters. Our two primary energy systems are: (1) fat-based, which allows for long slow steady walking across the Savannah (or the Queen K after dark); and (2) ATP-based, which gave our ancestors 20 seconds of balls-out sprint speed to escape the charging saber tooth tiger (or let grandma lift the ’67 Ford truck off gramps when the jack failed). We just weren’t designed to operate at high revs for long periods of time. Doesn‚Äôt mean we can’t, we can, but it’s at an appreciable cost that I will explain shortly. It just means we weren’t evolved to. Even our hunter-gatherer ancestors probably relied more on superior tracking skills and walking than they did running for hours or days after their prey. In fact, the energy costs of doing the latter were so high as to almost guarantee extinction. (Imagine your predicament when you run after an antelope for four hours and he gets away. Now you not only don’t have any food, you‚Äôve used up all your glycogen and, oops, there‚Äôs that frikkin’ saber-tooth again, licking his chops.)
The problem with many, if not most, age group endurance athletes is that the low-level training gets out of hand. They overtrain in their exuberance to excel at racing, and they over consume carbohydrates in an effort to stay fueled. The result is that over the years, their muscle mass, immune function, and testosterone decrease, while their cortisol, insulin and oxidative output increase (unless you work so hard that you actually exhaust the adrenals, introducing an even more disconcerting scenario). Any anti-aging doc will tell you that if you do this long enough, you will hasten, rather than retard, the aging process. Studies have shown an increase in mortality when weekly caloric expenditure exceeds 4,000.
That’s why I stopped racing and training ten years ago and why I prefer hiking, sprinting and weight-training today. But what’s a competitive type-A to do if s/he wants to kick age-group butt in Kona and NOT fade away prematurely?” Excerpt from Training Is No Guarantee of Health by Mark Sisson — a former sub-2:20 marathoner and a 4th place finisher in the Hawaiian Ironman