It was a Thursday, which meant Vikings sports nutritionist Carrie Peterson was making her rounds at Winter Park. She had a folder filled with the players' weights, body-fat measurements and a series of dietary game plans designed to help some guys lose bad weight and other guys gain good weight.

She reached the cafeteria, and nose tackle Letroy Guion greeted her with a big hug. You'd hug her too if she had given you the nutritional road map to get from 331 pounds in May to a physically stronger, athletically quicker 300 pounds for the start of your first season as an NFL starter.

"I'm still big, but I don't have all that fat to move around," Guion said. "I'm more explosive and I can play longer without getting tired. I feel great."

Peterson works at the University of Minnesota and is a consultant for all the pro sports teams in town. She started working with the Vikings in 2002, the year after 335-pound Korey Stringer died of a heat stroke.

"It's amazing to think that sports nutrition is such a relatively new piece to the puzzle when it comes to training and recovery in the NFL," Peterson said. "Nutrition is a science, so we know exactly how to help these players recover more quickly."

One player who wanted to recover more quickly was early NFL MVP candidate Percy Harvin, who basically treats his 195-pound body like a crash dummy on game days.

"Carrie actually was thinking of a new recovery plan for me before I even went to talk to her about getting one," Harvin said. "I wanted to help my legs recover quicker. She came up with some smoothies and stuff like that. Just different juices and Gatorade and stuff that have helped me bounce back from week to week."

Peterson described her job as being both nutritionist and part-time "den mother," especially to some of the rookies and practice squad players.

"When they leave here, it's not that they're trying to eat poorly," Peterson said. "Many of them just have no clue. They're 24, they're tired and there's a fast-food restaurant on every corner.

"I'll ask some of them, 'Do you need me to go to the grocery store and help you?' They'll walk into the grocery store and it's the deer in the headlights. But they've never shopped for food before."

Since Bryant McKinnie was released last year, Peterson said there aren't many "problem guys" on the team, nutritionally speaking. She says it helps tremendously that the team's two best players -- Harvin and running back Adrian Peterson -- are so devoted to good nutrition.

"Adrian has a personal chef that does his meals," Carrie Peterson said. "When the bigger-name guys buy in, the others will follow. Whether it's high school or the NFL, it becomes a little bit of a herd mentality when the stars are doing the right thing."

Guion agreed with that assessment.

"Those guys got the bodies that make everyone go, 'Wow,' " he said. "I want to eat like they do so I have one of those freak-of-nature bodies, too."

Then Guion smiled and popped open a Styrofoam food container filled with salmon and green beans.

Nose tackles eating salmon and green beans. Yep, the NFL has come a long way, nutritionally speaking.

Mark Craig • mcraig@startribune.com