Last month I discussed a posting by Richard Gibbens to his Web site, "Power Running", that took a stab at analyzing trends in the training of marathon runners over the past 30 years. Using a Running Times article as substrate, Gibbens did his best to force-fit author Jonathan Beverly's analysis to his own longstanding crank-a-wank conclusion: that logging the sort of mileage recommended by experts in the discipline isn't nearly as important as a means of improving performance as, say, is figuring out how talented you are or running really fast for brief amounts of time.
Now, Gibbens has even more interesting things to report: that training the heart and lungs isn't the cornerstone of improving aerobic performance -- training the muscles is.
Never mind that muscles can't work at maximum capacity in events lasting longer than about a minute unless supplied with sufficient amounts of oxygen, and that the heart and lungs have been known to play a part in furnishing muscles with this element; Richard nicely mangles the muscle-physiology aspect too, as explained below.
Gibbens is wed to the idea that muscle power determines performance even in long-distance events not because meaningful skepticism has led him there, but simply because he believes it makes him a revolutionary. He has yet to learn that using "conventional wisdom" as a slur is not a viable means of empowering ramshackle propositions, and he never will because he would rather be recognized and labeled a goofball than remain anonymous. Unfortunately I can only nudge him so far toward this honorable goal, but I'll have fun trying.
Gibbens' first several paragraphs essentially say "We all have training theories; here's mine and it's a doozy!" In the fourth -- equally dispensable but amusing -- he writes:
"If you are curious about the research data supporting this explanation please see all other articles on the Power Running web site, especially those in the physiology section. In fact much of the Power Running web site consists of the data supporting the explanation I'm laying out here. The supporting research data is all there, waiting on you."
For other examples of purely self-referential death spirals, please see "Scriptural support for God's existence: revised 193,498th edition."
Gibbens then moves to the meat of the matter, divided into three parts. The first, which carries the heading Performance is ultimately determined by your muscles, opens with this:
"You can only run as fast as you can run because your muscles aren't capable of moving you faster. When your muscles are contracting as fast and with as much force as they are capable of contracting, then that's it; that's as fast as you can run. A few lucky people are born with really powerful, fast contracting muscles that are amazingly resistant to fatigue. These folks run really fast. Most of us are born with average amounts of power, strength, speed, and endurance. We don't run especially fast. A few folks are, unfortunately, born with below average power, strength, speed, and endurance causing them to run slower than average."
Okay, now we know that some people naturally possess faster all-out sprint speed than others, but no one can sprint at infinite speeds; I can run faster than some people, but, alas, no faster than I myself can. Gibbens continues:
"Sure, there are exceptions to the above. For example, there are some people who are really fast at short distances but not so fast at long distances. We call these people sprinters. However, exceptions don't disprove the rule. After all you wouldn't say that just because there are some short people it proves that most people aren't of average height."
At this point point it's unclear why he makes the implicit observation that some people are physiologically better suited to racing long distances than to running the sprints; such sensible statements are not normally part of a Gibbens piece, and those out to establish the existence of "rules" are rarely seen giving due importance to crippling "exceptions."
But it's soon evident that he doesn't mean to admit this, as he whimsically attempts to minimize the tremendous importance of individual differences in innate muscle-fiber composition by insisting that although a wide range of human heights exist and fall along a bell curve to create a median, most people are actually median. That's right -- create a frequency plot of the heights of everyone in the world, and you'll see a "bell spike" with a few negligible outliers. Conveniently, this, according to Gibbens, applies not only to height but to other anthropometric parameters as well, as we shall see.
He continues:
"Obviously, endurance runners don't routinely compete at their top running speed. So, what's the relationship between your top speed and the pace you can sustain during longer events? Your top speed determines every other pace/distance that you can hold because properly trained muscles fatigue at a known rate. If you are familiar with prediction tables you already know this to be true; you are able to predict your performance at any distance based on your performance during another event, assuming proper training. Prediction tables work because the average person's muscles fatigue at a known rate."
I'm tempted to call out parts of this paragraph, but the entire thing is garbage. The relationship between top running speed and potential at the long distances is hazy at best; not only are the reasons for this well understood by anyone who has studied human physiology, but this lack of relationship can be easily demonstrated (and I'll do this tomorrow) by the use of Gibbens' anathema: real-world examples.
We're all born with a certain proportion of what physiologists call Type I ("slow twitch"), Type IIa ("medium twitch") and Type IIb ("fast twitch") muscle fibers, and these provide different amounts of input to given tasks by utilizing fuels in different proportions at different intensities for different optimal lengths of time. The proportion of each fiber type is largely fixed at birth, although some plasticity has been observed (see linked reference below).
The Type I are also called "slow oxidative," and these are your endurance-happy fibers; rich in mitochondria, they are far more important in aerobic metabolism (e.g., marathon running) than at gycolytic- and creatine-phosphate-based jobs (e.g., the 40-yard dash). Think of these as the "tortoise" or "mustang" fibers. The Type IIb, the "fast glycolytic," are at the other end of the spectrum, not especially useful in the long haul but fearsome contributors to power-based exercises like squat thrusts and bench presses, not as strongly reliant on oxgen and hence deemed "anaerobic" (a misnomer, but forget that for now). These are your "hare" or "quarter-horse" fibers. The Type IIa are "fast oxidative," something of a hybrid between the other two both structurally and functionally.
You can guess at the implications. Someone born with a lot of slow-twitch fibers is not going to have much luck turning himself into the next Asafa Powell, the world-record holder in the 100-meter dash (9.77 seconds). But Powell, for all his wondrous jets, would not be able to keep up with Kenenisa Bekele, the world-record holder in the 10,000 meters (26:17.5; that's over six miles back-to-back in under 4:14 each) in a race lasting longer than about 1 to 1 1/2 minutes no matter how sharply he were to slant his training toward the building of endurance.
Without consulting a zoology textbook, you can probably surmise whether the pectoral muscles controlling the wings of a hummingbird, which can beat at over 70 flaps per second, show a preponderance of Type I fibers and oxidative enzymes or whether they're rich in Type II fibers glycolytic enzymes. You should also be able to make some solid assumptions about the cellular characteristics of the leg muscles of cheetahs.
For a good clinical discussion of this, see this study and pay particular attention to this section. There are two important points -- ones I raised at the outset -- to bear in mind, and this article ties them together: Gibbens has a poor understanding of muscle physiology, and Gibbens grossly underestimates -- or ignores -- the role of cardiovascular factors in endurance performance.
I'll finish this on Sunday. I know this is boring for most, but if you've read this far and are at all interested, trust me, it gets a lot funnier.
