Did our cave-dwelling forebears feel nostalgia for the days before they were bipedal? Were hunter-gatherers convinced that swiping a gazelle from a lion was superior to that newfangled business of running it down yourself? And why stop there? Why not long to be aquatic, since life arose in the sea? For that matter, it might be nice to be unicellular: after all, cancer arises because our differentiated tissues run amok. Single cells don’t get cancer.
A humorous anecdote by Robert Sapolsky (the embedded viewer is not great, see a better version here):
Running is in our DNA is Asics' new ad campaign slogan. Much better than Reebok's Run easy campaign. I found the ads surfing around for information after the Chicago marathon was cancelled midway through due to heat. Came across a few forum threads about how endurance running was counter to our evolutionary past and how we should only ever sprint. Honestly, most of these sounded like people looking for excuses not to run, but there were a few thought-provokers.
"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’t 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."
This quote comes from an interesting piece that Mark Sisson wrote earlier this year. It's worth a read, and I think the argument he makes that chronic high-level training is bad for you is sound. It does, however, raise the interesting question of how endurance running factored into our evolutionary past. I've previously posted a review by Bramble and Lieberman that nicely summarizes the biomechanical and energetic evidence supporting the hypothesis that humans evolved for endurance running (we're pretty slow sprinters as well, relative to the rest of the animal kingdom). Bramble and Lieberman provide some good arguments against the idea that endurance running is simply a by-product of enhanced walking capabilities (see also this paper about what your ass muscles are for).
If not a by-product of walking, then what pressured the evolution of the numerous adaptations for endurance running? In 1984, David Carrier proposed that endurance running evolved to allow early hominids to run their prey to exhaustion, referred to as persistence hunting. Over time, the need for this declined as early humans developed more advanced hunting methods and tools (e.g., arrows), which is perhaps why modern hunter-gatherers rarely engage in endurance running. However, while rare, persistence hunting has been documented in modern hunter-gatherers (reviewed recently by Liebenberg). Persistence hunts covering 20-30 km (~10-20 mi) at average speeds of ~6 km/hour (~3.75 mi/hr) have been documented. This video shows a persistence hunt (from the BBC's Life of Mammals, higher quality version here):The pace is not continuous, but more akin to a fartlek. If I have time, I'll post later on energy systems use in this kind of effort, with some interesting data on marathon running.
To the future:
Elite marathoners giving Fair Chase.
An excellent post on persistence hunting can be found here.
The running man, revisited by
The painful truth about trainers: Are running shoes a waste of money? by
Wiggling their toes at the shoe giants by
A new report due out in PNAS measured the efficiency of bipedal versus quadripedal gaits in chimps. The authors find that in individual chimps, bipedal walking was more energy efficient than differed in energetic cost from quadripedal walking, with individual differences in anatomy and gait determining the more efficient method. These findings suggest that biomechanical changes and the accompanying energetics may have spurred the development of human bipedalism, which is far more efficient than either chimp gait.
So that's why the bear crawl is so painful...
Nice post on freezing fish. Maggie's mention of flash-frozen fish prompted me to buy several pounds of fish to try out; it's a hell of a lot cheaper than fresh fish but I'm skeptical that it will taste as good. Check out the rest of the blog (Atom feed), it's pretty informative and amusing (e.g., great photo tutorial on cooking whole fish and all of these amazing recipes).
What the world eats (TIME photoessay). Click the link or the photo to go see the whole series. It's really neat. This is my favorite:
Here are links to some articles about diet/disease/health that have caught my attention:
Some novel hypotheses from Frank Booth here and here. The cycling hypothesis is interesting, particularly so in light of the recent work by Mattson on caloric restriction and intermittent fasting. Background reading on paleolithic and hunter-gatherer diets can be found here. A discussion specific to dietary levels of protein can be found here.
My current macro-breakdown according to
