When it comes to fitness advice, who better to seek insight from than Olympians themselves? How about the people who taught those Olympians? Here are the words of wisdom that five world-class athletes live by.

Eric Shanteau, Team USA Swimming
"Don't get hurt training."
-- His weight coach, Doc Kreis

Sure, you have to push yourself hard to reach Olympic status, but push too hard and "that's when you'll do something stupid and hurt yourself," Shanteau says. Your move: Listen to your training plan unless your body is telling you not to, says Kristen Dieffenbach, Ph.D., a certified sports psychology advisor to the U.S. Olympic Committee. “The smart athlete knows what fatigue level to expect, and trains and adjusts accordingly." Signs of exhaustion? Small mistakes, posture or form faults, moodiness, or an increased/decreased heart rate that you can"t explain.

David Boudia, Team USA Diving
“See food like gasoline.”
-- His nutritionist, Jennifer Gibson

David Boudia can't afford to gain a pound in the wrong place.

"If your car takes premium and you put in unleaded, it'll destroy it. If I put nastiness in my body, I expect bad results,” Boudia says. Performing in front of millions in simply a Speedo is motivation to stay slim, but a poor diet also throws off Boudia’s game. “A five-pound weight gain affects how fast you spin. If you dive a good, trim line, the judges will score you half a point higher,” he says. Steal his secret: For an energy boost, throw two carrots, one apple, a few slices of pineapples, and a beet in a juicer. "I stick with raw, whole foods," he says. “That way I know what I’m putting in my body.” (Fill your plate with the The 125 Best Foods for Men.)

Jen Kessy, Team USA Beach Volleyball
"Mix up your routine."

Changing it up in the gym might be the secret to lifelong fitness. Maybe that’s why Jen Kessy, a standout on Team USA Volleyball, has been in the game so long. In fact, research shows it to be true: When 52 people were broken up into three groups -- one that varied its workouts, one that did the same thing every time, and one that had no regulations -- most of the people who dropped out of the study were from the group that didn’t switch things up, according to a University of Florida at Gainesville study. The group that varied its routines found exercise 20 percent more enjoyable than the other groups. (Ready for a change? Try the brand new DVD series from Men’s Health, SPEED SHRED. It’s full of never-before-seen exercises that will torch fat and sculpt every muscle in your body!)

Trey Hardee, Team USA Decathlon
“If you really want to be serious, listen to the people who are trying to make you better."
-- A coach from another high school when he was younger.

Hardee describes his former self as a butthead high school kid who just loved to pole vault. He was good at things you can’t coach: He was tall and fast. “I never warmed up, cooled down, or did anything to take care of my body.” That is, until a coach from another high school told him to smarten up. Since then, he’s been focusing on the whole picture, and it’s paid off. Since high school, Hardee has transformed into a two-time consecutive world crown holder, NCAA and U.S. National champion -- and, oh yeah -- two-time Olympian.

Allyson Felix, Team USA Track & Field
”Train with friends.”

This sprinter hates running -- for long distances, that is. What’s her trick for keeping herself honest? Making a promise to a friend that she can’t back out on. But you won’t find her being buddy-buddy on the track on race day: When it comes down to the wire, you need to zone everything out and focus, she says. After all, “You can be prepared, and super, super physically ready, but if you don’t have that mental portion, it can all fall apart.” (Allyson Felix is one of our 12 Hottest Female Olympians. Click to see who else made the list!)

Additional research by Madeline Haller
Photo Credits: David Boudia - PMG Sports, Trey Hardee - Justin Kosman/Red Bull Content Pool

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