Too much cardio... (Read 2649 times)

This is the problem, though, with the term "economy." It's a concept that picks out what is basically an unmeasurable quantity. It's an attempt to cover over the inability of the sum of physiological concepts to adequately map the total experience of running by inventing a catch-all term that refers to "that which could not be discovered in the lab." The lab says Runner B should be as fast as Runner A. When this turns out not to be the case, economy is invoked as an "explanation." But nothing has been explained: a word has been placed at the site of the ignorance, as a way of covering over that ignorance. This happens all the time, and not just in physiology.

I agree that it is impossible to isolate stride efficiency and that makes running economy impossible to use quantitatively. However we cannot discount the evidence that stride efficiency plays a very significant (much moreso than VO2Max) role in running. It's just a simple application of Occam's razor once we observe that: elite runners have a stride which is very similar to each other but very different from casual runners, VO2 Max or LT based metrics are not good predictors of race results, the metric that is best at predicting race results is dependent on stride efficiency, and we have such a competitive environment that given the law of averages, external factors are minimized at the elite level. We also have years of training lore suggesting that strides and short track repeats make people faster at any level of effort. There just isn't another way to explain it other than: efficiency plays a large role in running.

I thought we were talking about Hippos and the length of Milton Berle's member?

Without googling: pluralities should not be multiplied unnecessarily. But William of Occam (or Okham) was arguing against certain Catholic views, not for a specific direction that scientists should take. However, his razor oft rings true. RunningBehind, my only argument is with whether any of this has to do with caloric expenditure rates over distance. Not with oxygen consumption, stride efficiency, etc. And I am not arguing against Noakes and Daniels (who themselves argued against each other).

Running fast for 2 miles burns more calories than running slow (or walking ) for 2 miles.

Yes. But only if you weigh more while running the fast 2 miles. Otherwise, it is about equal.

Probably not. But then again, that is not really running.

Why not? That's the way a lot of people run at first. Then, with practice, they become more efficient.

Right, and this gets to Jeff's point about running in place and (I believe) RunningBehind's point about improved efficiency. Comparing different runners or single runners at different stages in their running career or different running-like activities is apples to oranges. There are too many variables that impact the energy expenditure, including whether the forces are directed horizontally or vertically, whether other body motions are included in the effort. However, for a single runner at a given stage in his or her training, whether running 8 m/m or 11 m/m, the calorie burn rate is essentially the same per mile. This is not impacted by (or well measured by) VO2.

Inefficiency will increase energy burn. Most people who aren't highly trained are probably less efficient while running (for a variety of reasons) than when walking so in most cases running will burn slightly more calories than walking, up to 15% or so.

What do you mean by altering stride? Taking shorter or longer steps? Or bouncing excessively and unnaturally?

Well, if you take longer steps without changing speed, this probably means you're "bouncing" more, right? If this causes you to burn more calories, then I'd call it "bouncing excessively."