Boxing might be the most quintessentially masculine sport. One might say it's even comically masculine, the sport of Hemingway and Ron Swanson, and the medium Rocky once used to symbolically destroy the Soviet Union.

But it takes more than machismo and bravado and chutzpah and other synonyms for “ballsiness” to come out on top in the ring—like any other sport it takes diligence and discipline. Just ask Shawn Porter, the 28-year-old former welterweight champion who has a pro record of 26 wins, one loss, and one draw. Currently, the boxing world is on edge waiting for the announcement of a long-promised fight between Porter and the current welterweight champion, Premiere Boxing Champions’ fighter of the year, Keith Thurman (26 wins, 22 KOs).

Porter’s diet changes up for heavy workout days, usually with sparring, long-distance running, and afternoon swimming (rest days involve bike riding, yoga, and massage), but he also has to shake it up daily depending on his morning weigh-in. “Depending on what we see or what we want to see, we’ll have more or less of something. I might have oatmeal before I do a track workout, but depending on what the weight is I might have half a cup of oatmeal instead of a whole cup.”

That might sound meticulous and anal, and, well, it is. But it pays off. Many athletes wind up eating the same meal routinely to cut down on the number of decisions they have to make (if you’re exhausted and trying to figure out you’re next meal, you’re more likely to say “fuck it” and order General Tso’s), but Porter has taken meal-planning to Jetsonian levels, often having a bulk order of tilapia vacuum-sealed and portioned out for the week.

“It keeps everything fresh,” he says, “and there have been instances where I was supposed to have tilapia on Monday, but because my weight wasn’t where I wanted it to be that day I didn’t eat it then, so I had to hold off eating that particular piece for another day or two. You don’t have to worry about something not being fresh, or re-cooking it, or not cooking it through already.”

Because of the nature of boxing and the weight divisions, Porter puts a premium on his weight (welterweights have to fall between 140 and 147 lbs.). He describes his average meal as “not too much, but enough to keep me going.” The one time he really cuts loose is the day before a fight, after the weigh-in. “That’s my favorite part, man,” he says.

“I love to have lasagna the day before I fight. Obviously the carbs are loaded, but it’s also my favorite food. So I’ll have lasagna and mixed vegetables and maybe some chicken breast.”

When he’s not going full Garfield, his usual go-to meal is a unique mix of brown rice, tuna, tofu, and garlic. It’s a quick pre- and/or post-workout staple that delivers a lot of protein and carbs, and Porter gets creative to punch up the taste. “Sometimes I add pickles or pickle juice just to give it some flavor, since I don’t eat a lot of salt during training.”

BreakfastGrapefruit

Pre-runBrown rice, tuna, tofu, garlic mixture

Post-run, pre-swimMixed nuts

DinnerTilapia, brown rice, small salad

Luke Darby is a contributor to GQ, covering news, entertainment, and the environment. A Louisiana native, he now resides in Cleveland, and his writing has also appeared in Outside, the Dallas Observer, and Marie Claire.Related Stories for GQReal Life DietBoxingHealthBoxingHealth