At the starting dock of the Olympic triathlon trials, the expression on Andy Potts’s face seems to say I will kill you with my eyes. As the starting gun fires, he plunges into the Black Warrior River in Tuscaloosa, Alabama, and, in a burst of white foam, quickly pulls ahead of nine rivals. The second-ranked Hunter Kemper manages to hold pace with Potts for a few minutes, then drifts back into third place.
Potts’s lead grows relentlessly to five body lengths as the rest of the field fans out behind him. He should dominate this Olympic-distance race—a 0.9-mile swim, 24.8-mile bike ride and 6.2-mile run—just as he dominated last year’s national championships and Pan American Games. He is, after all, the number-one-ranked triathlete in the U.S. Within minutes, he extends his lead to 30 lengths and swims for the shore alone.
His coach, Mike Doane, paces along the river’s edge. “When he can get his heart rate up around 165, he has a great race,” Doane says. Any higher than 165 beats per minute, and he’s using too much energy too early. Much lower—say, below 140 on the swim—and it means that he’s too tired to generate the tempo that would get his heart rate up.
Potts leaps out of the water, charges toward his bike, and zooms onto the cycling course 38 seconds ahead of Kemper. His heart rate, monitored by a microcomputer on his wrist, is right where it’s supposed to be: 165. As Potts speeds by, Doane yells to him, “Forty-five-second lead!” Kemper and three others whip by in a thick pack. Potts zips past to begin the second of eight three-mile loops. “Thirty seconds!” The third time: “Twenty-five seconds!” They’re gaining on him.
Potts signals to Doane that he’s going to slow down and draft off the pack to save energy. Doane nods. Potts’s heart rate drops to the 140s. The foursome, reaching 30 miles an hour, soon gobbles him up, and for the next 20 miles, Potts and Kemper remain axle-to-axle. Potts’s heart rate drops to 127: He’s getting a free ride. Doane presses his lips together and nods. His athlete is on track for an easy win. The numbers are perfect.
Stay up to date on the latest news of the future of science and technology from your iPhone with full articles, images and offline viewing
Featuring every article from the magazine and website, plus links from around the Web. Also see our PopSci DIY feed
Share links with friends, comment on stories and more
In our December issue, Popular Science names the 100 best innovations of the year: bombproof wallpaper, self-parking cars, the fastest helicopter, and 97 more. Plus inventor profiles and videos.
Check out the best of what's new here.

have they tried to do something along the lines of subjcts ing a peron to an enregy field to see whether that would either change their performance r allow someone to measure variations, which can the be corresponded to the bodies energy output.
http://the.nerd.herd.group.googlepages.com/
This article was all well and good, but for high-ish level athletes none of this was new news. Many full-time athletes monitor restfullness by benchmark values on a wattage trainer, various heart rate "tests" etc... and adjust training load according to these values. This was just a long article telling the story of an American triathlete without much in the way of detailing "highly scientific training regimens".
He did not make it to the Olympics.
I enjoyed the article. I have done a couple of sprint triathlons and some marathons so it may have appealed to me more than other people.
I'll settle for a simple workout and some protein shakes, Then again, I don't plan to make the Olympics. My new invention is just fine for me, check it out at:
www.urbanchicsoap.com/fit
and a NASA sponsored contest at:
http://www.createthefuturecontest.com/pages/view/entriesdetail.html?entryID=1346
This was a great article which not only detailed the struggles of one olympic athlete along with his training regimen, but it gives insight on the novelty of feedback training focused on physiological and biological parameters (direct results of excersice and training such as heart rate) rather than their consequences (Since heart rate has been controlled, the athlete may run longer or faster, etc...) I think that the idea of measuring these parameters not only periodically but constantly throughout practices is definitely a wonderful tool for training and athlete's development since, as stated in the article, it provides a very good measure of the athlete's response to the previous training and whether rest or more training is required for future workouts.
This wonderful short story is exceptionally presented with a great introduction to the athlete, a moderate level of technical explanations worth of Pop Sci and very inspirational. Thank you Cohen.