Why We Run by Bernd Heinrich

Author:Bernd Heinrich [Heinrich, Bernd]
Language: eng
Format: epub
Tags: Wildlife, Running & Jogging, Animals, Sports & Recreation, Nature
ISBN: 9780061979996
Google: UEw4eN-5kgsC
Publisher: Harper Collins
Published: 2001-01-02T00:00:00+00:00

ELEVEN

Athletic Frogs

In Mark Twain’s famous story about the Calaveras County jumping frog, the frog’s owner, the “infamous Jim Smiley,” was challenged by a stranger who asked, “Well, what’s he good for?” Smiley replied, “easy and careless,” that “he’s good enough for one thing, I should judge—he can outjump any frog in Calaveras county.” Of course, we all know the outcome: the frog didn’t budge, because when Smiley went out into the swamp to find a challenger for the bets that had been placed, the stranger stuffed the notorious jumping frog full of lead quail shot.

Since Mark Twain’s time, frogs have budged a lot. When unencumbered, they’re quite impressive at performing a rapid series of long jumps in a short time, that is, sprinting, using both legs at the same time. The current champion is a bullfrog named Rosie the Ribiter, who competed in the now-annual Jumping Frog Jubilee at the Angel’s Camp fairgrounds in Calaveras County. She (?) set an all-time world record for a three-leap total, which is how the record is judged, of 21 feet 5.74 inches. That’s not quite up to par with Bob Beamon’s famous Olympic record of 29 feet 2.5 inches in the long jump event, but for a frog, covering more than 21 feet is impressive, even if it does take her three jumps.

A frog’s leg muscles are designed for quick, explosive releases of energy. Frogs, just like sprinting cheetahs or humans, burn carbohydrates without the immediate use of oxygen, that is, anaerobically. Anaerobic performance never goes unpunished—in seconds the critter gets laced full of lactic acid and its muscles tie up. Undoubtedly, if Rosie had continued with more than three successive mighty jumps, there is good scientific evidence that each successive jump would have become very much shorter.

People do some pretty odd things to satisfy their curiosity. A colleague of mine at the University of California used to chase lizards on a miniature racetrack until they could go no farther. Then he grabbed them and ground them up in a blender and measured how much lactic acid they had generated. By assaying lizards after varying sprint durations, and at varying postsprint intervals, he was able to determine that it takes some lizards an hour or more to get rid of their lactic acid load. Frogs operate under the same constraints, and air-breathing divers who stay underwater without access to oxygen suffer the same lactic acid accumulations. There is no grand discovery here—just a reaffirmation of what we all know from personal experience. We can’t sprint or hold our breath if we want to go far. Sprinting in the middle of a race is not to be recommended. The sprint must come at the end, because you can pay off the oxygen debt when you’re done.

Some frogs, unlike Rosie, are ultraendurance athletes par excellence, and they annually stage their own remarkable contests. These contests are performed strictly by males, and the contested skill is in aerobic shouting, not anaerobic jumping. The prize is copulation with female spectators.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.