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Silver medalist Dawn Harper will stick her finger in some grease, she said, to fulfill her need for junk food.

For four long years, they have resisted the siren call of the greasy hamburger and the enticing whispers of the milkshake. 

Now that their competition in London is done, several U.S. Olympians are done fighting the urge to break their strict diets. Bring on the fries, pizza and steak, and let 100-meter hurdles silver medalist Dawn Harper show the way.

“I want something bad,’’ Harper told TODAY.com. “I will find grease and dip my finger into it.’’

Clive Rose / Getty Images

Gold medal-winning swimmer Matt Grevers celebrated his Olympic run with a run to McDonald's.

When Harper finally returns to her home in East St. Louis in late September at the end of the international track season, she wants her family to pretend it’s late November.

“This is really bad,’’ she said. “I told my family I want a Thanksgiving meal prepared, with all the fixings.”

Before she gets to her turkey feast, Harper will have to settle for something frozen in London. She plans on having some Pinkberry, “since there’s no Cold Stone.’’

Swimmer Matt Grevers had something similar in mind after he finished his competition with a gold medal in the 100-meter backstroke and a silver in the 4x100-meter freestyle relay.

“I went to McDonald’s and had a vanilla milkshake,’’ he said. “It was delicious.”

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Gymnast John Orozco had a feast that "destroyed" his stomach after competition was over.

When these finely-tuned athletes are ready to stop counting calories, their bodies aren’t always ready for the shock of a cholesterol tidal wave.

“I had pizza, chicken nuggets from McDonald’s, and I had a big cookie,’’ gymnast John Orozco told TODAY.com. “That was it for me. After that my stomach was destroyed.”

The 19-year-old from the Bronx was on a diet of protein, lean meats and salad leading up to the games, where he did not earn a medal in the individual or team competition.

“Maybe that (diet) didn’t work for me,’’ he said. “I was too weak.”

Watch video: Olympians reveal nicknames from serious to silly 

Gregory Bull / AP

Aly Raisman's post-games guilty pleasure is pizza, while teammate Gabby Douglas is going to hit up a Mongolian grill.

The guilty pleasures of Orozco’s gold medal-winning counterparts on the women’s gymnastics team run the gamut from pizza (Aly Raisman) to a Mongolian grill (Gabby Douglas), while U.S. shooter Jamie Gray made a special order after winning the gold in the 50-meter rifle three-position.

“I’m a healthy eater, normally,’’ Gray said. “[After competing] I went to the USA House and had a nice rare steak. It was awesome. They didn’t have it in the buffet so the chef made it and brought it out himself.’’

Not all athletes go completely off the wagon. “[I want] a giant slice of gluten-free pizza!’’ said pole vault gold medalist Jenn Suhr. “I follow a gluten-free diet, but I can’t wait for some good pizza.’’

Food cravings are also a reminder of home for the Americans thousands of miles across the pond. Mexican-born distance runner Leo Manzano, who became the first American to medal in the 1,500-meter race since 1968 when he took silver, is craving some of his mother’s flour tortillas at home in Austin, Texas.

Watch video: Athletes reveal which royal makes them swoon

“Flour tortillas are not as good for you, but they taste better,” he said.

Fellow Austin resident Michael Tinsley, who won the silver medal in the 400 hurdles, has his own hometown agenda.

“I really want to have a burger from Mighty Fine,’’ Tinsley said. “They have the best burgers in Austin. They’re big and juicy and neatly made!”

Some Olympians aren't craving food, but company: Suhr said her first order of business when she gets home will be going to the babysitter to pick up her dog, a Great Pyrenees named Tundra, and her cat, Morris.

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Missy Franklin smooches her pooch, Ruger. The two Skyped while she was in London.

Swimmer Nathan Adrian is also waiting to see his dogs, a pair of pound puppies named Boo (after the character in "Monster’s Inc.") and Sully. Adrian said he has been Skyping with his family but since you can’t Skype pets, he has missed his dogs.

Don’t tell teenage swimming phenom Missy Franklin that you can’t Skype with pets. Franklin pined for her 9-year-old, 110-pound Alaskan Malamute named Ruger so much that she had a Skype session in London with the canine simply sitting in front of the camera. When she gets home to Centennial, Colo., she plans to “cuddle my dog for like 20 days straight.’’ 

Finally, if there aren’t any pets or burgers waiting for them at home, Olympians could always blow off steam the old-fashioned way, like Grevers plans on doing.

“I want to stay out late and socialize,” he said.

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Shawn Johnson: 'Going to London is bittersweet'  

After a disappointing performance on the pommel horse at the start of Wednesday’s all-around finals, U.S. gymnast Danell Leyva draped his lucky blue towel over his head in silence.

A few hours later, he replaced it with a bronze medal around his neck. Meanwhile, his towel was busy gaining thousands of new Twitter followers.

Leyva appeared on TODAY Thursday alongside his stepfather and personal coach, Yin Alvarez, and U.S. gymnastics teammate John Orozco to talk with Savannah Guthrie about his good luck charm.

What started out as a joking superstition five years ago has become a mechanism for Leyva to focus when his mind tends to wander. The old blue towel with a star pattern has become a celebrity in its own right, as its parody Twitter account, @LeyvasTowel, now has 10,000-plus followers, rapidly gaining on the 50,000 on Leyva’s account.

TODAY

Danell shows off his lucky towel.

“At first it was just a lucky towel, but it has turned into so much more than that,’’ Leyva told Guthrie. “It has turned into something that really helped me get into the zone and into the concentration of my routine because I tend to get distracted way too easily. It really helps.’’

The towel celebrated all the attention surrounding Leyva and his good luck charm after Wednesday's performance by tweeting, "OMG! It's a fluff piece all about meeeee!"

Leyva, 20, has had the lucky item by his side since 2007. While one aunt went to buy a towel, another aunt went to retrieve one from her house, and they both came back with the same exact type of towel. He kept both of them, and one of them ripped later in 2007. The remaining one has been his constant companion at competitions for the past five years.

Another constant at his competitions has been Alvarez. His rhythmic clapping, ritual kissing of Leyva’s forehead and other routines have become a regular part of Leyva’s performances.

“It’s something that I do every day,’’ Alvarez told Guthrie. “I do it with all my athletes since Danell was a little kid, and I still do it with the little kids. It’s something that I do. That’s me. That’s my routine.’’

“I’m very, very lucky to have him there with me the whole time,’’ Leyva said. “It’s amazing. We have such a huge connection since I was really young, since I started. To have not only him but also my mom here…I feel very, very lucky.’’

Alvarez and the lucky towel helped Leyva focus on Wednesday after he struggled on the pommel horse at the beginning of the all-around finals and had to recover on the other apparatus in order to earn a medal. His score of 90.698 was good enough to make him the first U.S. men's gymnast to earn a medal in the all-around since Paul Hamm won gold in 2004.

“I didn’t have the best pommel routine,’’ Leyva said. “I kind of messed up. (Alvarez) came over to me and said, ‘Don’t worry, nothing happened. Just relax and do what you do every day.’ We both knew that my strongest events were at the end, and I just have to show off and do what I do.’’

Orozco didn’t fare as well, as he ended up finishing out of medal contention in eighth place in the all-around competition. He and Leyva both told Guthrie they plan on competing in the 2016 Olympics in Rio de Janeiro.

“This whole experience, it’s been a real journey for me,’’ Orozco said. “I didn’t quite have my big dream moment like I was hoping for, but just making it here and competing at the Olympics, I know that there’s thousands -- if not millions -- of kids that wish they can compete at the Olympic Games just like I did here in London. I’m grateful for the opportunity and I’m still glad that I got to go up there and compete for Team USA.’’

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