Conventional wisdom dictates that you shouldn’t eat half an hour before you go swimming. But what if you’re an Olympian and you need energy to swim really, really fast?

And what of the old adage, ‘you are what you eat’? Are our swimmers munching on gold medallists of old? Seriously, has anyone seen Kieren Perkins lately?

We’re fairly certain Mack Horton wasn’t chomping on the bones of the former champ before he won the 400m freestyle, but it does beg the question: WHAT ARE THESE PEOPLE EATING?

All pretty excited to be getting our Olympic uniform! #roadtorio #oneteam

A photo posted by Bronte Campbell (@bronte_campbell) on Jun 29, 2016 at 6:24pm PDT

Short answer: CARBS. Slightly less-short answer: A LOT OF CARBS (and a bit of protein).

After winning gold last night, America’s Michael Phelps reportedly indulged in just under half a kilo of pasta, which is around four times what an ordinary person might eat at dinner — or, I guess, twice what an ordinary person with a hangover might swallow.

As for Horton, well, it appears yesterday he smashed six times the cereal I managed on my Monday morning.

Basically, it’s important for athletes to replenish all the energy they’re burning in the pool.

Cheat Day Cakes #StacksonStacks #SwimmersDiet A photo posted by Conor Dwyer (@conorjdwyer) on Oct 4, 2015 at 8:41am PDT

It’s a bit more complex than that though, according to Dr Helen O’Connor, a sports dietitian who was in charge of the nutrition kiosk at the 2000 Sydney Olympics.

Watch: An easy (and delicious) superfood breakfast bar recipe. (Post continues after video.)

“An athlete’s fuelling strategy plays just as much of a part as their overall strategy,” Dr O’Connor told Mamamia when we spoke with her last week.

“What they eat, when they eat, both food and fluid as well as lifestyle considerations (such as getting enough sleep and beating stress) play a part.”

What can I say? She is a domestic goddess ???? @bronte_campbell A photo posted by Cate Campbell (@cate_campbell) on May 30, 2016 at 3:09am PDT

“Generally they’ll consume around 1600 through to five or six thousand calories daily, depending on the size of the athletes.”

Been a long and tiring week. Calls for jumbo size coffee!!!! A photo posted by Alicia Coutts OAM (@alicia_coutts) on Apr 13, 2016 at 5:06pm PDT

While it varies across sports, Olympians will often taper their eating habits as they taper their training habits in the lead up to their events.

@emcbomb with a cookie smile before her big 200s this morning A photo posted by Bronte Campbell (@bronte_campbell) on Jul 27, 2014 at 12:53am PDT

Some also supplement their diets with vitamins, protein powders and gels.

Unpacking the important stuff! Big thanks to @international_protein for supporting me in my lead up to Rio! #ipnation #supplements #fitness #health A photo posted by Keryn McMaster (@keryn_mcmaster) on Jul 22, 2016 at 6:59pm PDT

But what are they eating solids-wise?

Well, normal healthy stuff… with a little bit of junk on the side. They’ve earned it.

Feeling like someone at @bodyscience understands my love for cookies ???? Cookie dough and Cookies and cream protein bars ???? and all in the name of recovery and fuel ????

A photo posted by Jessica Ashwood (@jessica_ashwood) on Jul 11, 2016 at 2:59am PDT

“It’s healthy eating. Fresh produce, fresh fruit and vegetables, lean meats like chicken. Carbs and protein are important for recovery,” Dr O’Connor explained.

“So depending on the type of training, bread, rice and pasta would be eaten in the few days leading up to the event.”

isn’t a better place to eat chicken katsu ????????????excited to start racing tomorrow at the Japan Open ????????   A photo posted by TAMSIN COOK (@tamsincook) on May 19, 2016 at 1:14am PDT

Alright guys, you’re making us hungry now.

Want more? Mamamia founder Mia Freedman speaks with Leisel Jones about life after Olympic glory:

Feature image: Instagram