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AS JORDAN GROSS jogged off the field at Bank of America Stadium against the Giants, Panthers fans cheered and high-fived him without knowing exactly where he was headed.

Gross just couldn't ignore the urge any longer. Maybe it was the humidity or all that sweet tea, but in 2013, after a decade of playing tackle in Carolina, Gross had finally reached his bathroom breaking point. It's simple math, really: Players drink gallons of water but can't leave the field for even 30 seconds for fear of a turnover happening midstream. Over the years, Gross had tried every technique NFL players and other hyper-hydrated athletes use to surreptitiously relieve themselves during games. He'd experimented with the time-honored slow release into his pants, but they were white, for starters, and it just left Gross feeling soggy and slow. He kind of enjoyed the "T-Pee curtain" method, going inside a hut of towels or parkas. But worrying that his teammates would prank him by walking away midflow occasionally gave Gross stage fright -- aka paruresis, or what urologists refer to as "ballpark bladder." His tight pants, no-fly spandex and all the tape on his gloved hands and mangled fingers made it cumbersome to kneel behind the bench and pee into a cup (a method that was so popular among his teammates that rookies often had a hard time differentiating which cups contained actual Gatorade).

And so, in one of the final home games of his career, during a TV timeout with the defense on the field, the three-time Pro Bowl blocker figured he had nothing to lose -- he would proudly march off the field toward a small bathroom used mostly by field staff, where for once he could pee in peace.

Or so he thought. Inside the bathroom, Gross was almost immediately slip-sliding around the polished concrete floor in his cleats and struggling mightily with his gloves and pants. When his sweaty, dirty shoulder pads bumped the temple of a fan in a Cam Newton jersey next to him, Gross realized proper urinal etiquette required him to attempt small talk.

"Heck of a game," Gross blurted with a nod to the dumbfounded fan.

"The guy is staring at me, and I'm fully aware of how weird this situation is, and now it's all delaying the pee process," says Gross, who, sources say, was in too much of a hurry to wash his hands. "Poor guy probably paid a fortune for a field pass because he wanted to know what it was like behind the scenes at a big-time sporting event. Well, now he knows."

Former Panthers tackle Jordan Gross was no fan of the slow-release method popular among many of his brethren. Streeter Lecka/Getty Images

THE SHEER FREQUENCY and powerful pull of the pee break makes urine perhaps the most influential and disruptive liquid in sports. In fact, the most basic of bodily functions is such a potent force that it causes even the most disciplined, trained bodies in the world to do some wonderfully weird and occasionally revolting things. "Every single athlete has to deal with this in a different way, but one thing is the same: No one ever talks about it," says Jocelyne Lamoureux-Davidson of the U.S. women's national hockey team. "It's a pretty universal thing we all share, relative to everybody: Everyone has to go."

In 2012, Angels pitcher Jered Weaver was just three outs from a no-hitter when faced with that familiar conundrum. To everyone's great shock, Weaver dismissed more than a century of baseball superstition and bolted off the bench and down into the clubhouse bathroom with his knees pinched. That's just how ferocious nature's call can be: Sports immortality suddenly pales in comparison to the sweet relief that comes with release. Weaver, though, returned to the mound and, unburdened, put away three more batters to become the 10th pitcher in Angels history to throw a no-hitter.

By taking relief duties into his own hands, Weaver made a decision that validated a groundbreaking paper published the same year by Brown University. In it, neurology professor Pete Snyder found that the painful need to urinate impairs higher-order cognitive functions -- things like rapid decision-making, problem-solving and working memory -- on a level analogous with drunken driving.

"Imagine you're an athlete, you've just consumed a ridiculous amount of liquid on a hot day, you can't get off the field and you're in terrible pain," Snyder says. "When we're in pain, our first reaction is to act like any other animal and lessen the pain and get out of harm's way no matter what."

Snyder explains that there are centers deep within the brain that maintain homeostasis, or normal bodily functions such as breathing, heartbeat and urination. The pain and disruption caused by holding urine for too long essentially sets off alarms that dampen cognitive activities in the frontal lobes -- the ones athletes especially rely upon -- in order for the body to manage more proximal problems.

Snyder fed his subjects 250 milliliters of water (roughly 8.5 ounces) every 15 minutes until they reached their "breaking point." That intake, though, is just a drop in a bucket compared with what most elite athletes must consume in a never-ending process of keeping their bodies hydrated through daily cycles of perspiration, urination and rehydration. A 300-pound football player needs 192 ounces of water daily to maintain normal hydration. On game day in hot climates? He'll need another 128 ounces to replace the gallon or so of body weight he'll sweat out in the trenches. That means his intake on Sundays alone should be roughly enough to fill a small fish tank. And Snyder says the pain caused by trying to hold back all that fluid can create the same level of cognitive impairment as staying awake for 24 hours straight. All of which led Snyder to a single, deeply scientific conclusion for athletes:

When ya gotta go?

Go for the gold.

During his playing days its rumored Manny Ramirez used the Green Monster as his personal outhouse. Jim Rogash/Getty Images

Thanks to Snyder's study, it now makes perfect sense why Michael Phelps, the greatest Olympian of all time, admits he lets loose in the pool. It might even provide a scientific explanation for the Red Sox phenomenon known as "Manny being Manny." In 2005, during a pitching change in Boston, outfielder Manny Ramirez claims to have stepped into the Green Monster to relieve himself -- an urge so bad he almost missed a pitch. ("I'm just glad he came back," said Sox skipper Terry Francona.) It also explains one of the NFL's dirty little secrets: At any given moment on a sideline, someone probably is relieving himself while hiding in plain sight. Or trying to. Former Dolphins linebacker Channing Crowder's solution was fairly simple: He says he wet his pants ... in every one of his 82 games as a pro. As the Chargers drove toward a late field goal in 2011, kicker Nick Novak got caught kneeling by the bench midact, thanks to a CBS camera that lingered just long enough for the shot to include a graphic that suggested Novak's "target" was the 34-yard line. He fell a little short.

He also missed a 53‑yard field goal.

In Detroit last season, a Lions fan attending the game with her two children captured Washington special-teams coordinator Ben Kotwica relieving himself next to an equipment crate adorned with the NFL logo. Although the box failed to provide any actual cover, it did create an exquisite moment of brand marketing with the resulting viral photo, which captured Kotwica fully exposed and in full stream just inches from the revered NFL shield.

Public urination in Detroit anywhere other than the Lions sideline can cost you up to a year in jail and a $1,000 fine. But there are no rules against bathroom breaks in Roger Goodell's NFL. And so it is that players celebrating too much after a touchdown can often expect a hefty fine, while coaches and players are free to do the pee-pee dance on the AstroTurf.

"Guys are peeing all over the sideline in every game, into cups, on the ground, in towels, behind the bench, in their pants, everywhere," says Panthers center Ryan Kalil, who covered this topic and others in The Rookie Handbook, co-authored by Gross and Geoff Hangartner.

"You'd be surprised, honestly, how many players on the sidelines just go. I guess as athletes we are all desensitized by the whole peeing-everywhere thing."

WHEN IT COMES to urination, elite male athletes fall victim to a kind of Superman complex. Flying around in a skintight bodysuit and zipperless codpiece, what does Superman do if, god forbid, he needs to pee in the middle of saving Metropolis for the 87th time? Our minds don't associate athletes with something as vulnerable or mundane as needing to pee. As a result, they often perform in billion-dollar facilities that have retractable roofs and moon-sized video screens but lack a single toilet within reach of the field. "There is this level of invincibility and super-hero-ness to what we do as athletes," says former NFL lineman and ESPN analyst Mark Schlereth, whose infamous in-game toilet habits helped earn him the nickname Stink. "It's like that children's book Everyone Poops. In sports, everybody pees."

But the need to stay hydrated, combined with a maze of cultural hang-ups and poorly designed facilities, creates a nightmare for athletes who are just looking for a bathroom break.

So many runners in the New York City Marathon pee off the sides of the Verrazano-Narrows Bridge at Mile 1 that race veterans can only giggle when they hear first-timers below them on the lower deck talk about the sudden "refreshing" rainstorm they experienced. World-class cyclists still speak in awe of the balletic way former Tour de France racer Dave Zabriskie was able to straighten his right leg, stand tall in the saddle and urinate off the side of his bike while whizzing through the French countryside at 30 mph. In 2005, when Zabriskie became just the third American to wear the appropriately named yellow jersey, it earned him the privilege -- according to the Tour's unwritten rules -- to decide when, where and for how long the peloton was allowed to pee. "That's when you know you've made it in our sport," says former teammate Christian Vande Velde. "It's like, 'I just made the whole peloton stop and pee; I'm the man.'"

Because of cultural and anatomical obstacles, female athletes are forced to plan better and hold longer than their male counterparts. Members of the U.S. women's hockey team have even been known to use the expulsion of urine to measure the force of an opponent's checks. After a big hit, says team member Monique Lamoureux-Morando, "you get to the bench and people are joking about it, and you just go, 'Yeah, crap, she just made me tinkle a little.'"

Brandi Chastain, a member of the iconic 1999 U.S. women's national soccer team, leaked into her cleats only once -- during one of her first World Cup practices in Haiti. She remembers it fondly. "Absolutely liberating," she says. "It's hard to feel loose when you have that kind of tension in your bladder."

If a glimpse of Chastain's sports bra after her Cup-winning penalty kick in 1999 caused such a ridiculous uproar, she can't even imagine what fans would do if a player today copped a squat by the U.S. bench during a game, as so many of her male counterparts do. That single disparity can often leave female athletes at a significant disadvantage. It's common for female athletes to drink less -- and therefore perform worse -- simply because they're worried about how, or where, they'll go to the bathroom. During a recent U.S. Olympic Committee golf outing in Oregon, when Chastain mentioned this dilemma, a female golfer in her foursome cursed out the male-dominated world of golf course design, then produced something called P-Mate. The disposable cardboard device, made by a company in Broomfield, Colorado, allows women to pee in public while standing. "I was a little embarrassed at first," Chastain says. "Then I was like, 'Oh my god, this is awesome!' It's very different for the rest of us. You just can't squat in the middle of a Women's World Cup game. Male athletes can just create their own bathroom."

Former U.S. women's national soccer team player Brandi Chastain says female athletes have a tougher time than their male counterparts: "You just can't squat in the middle of a Women's World Cup game. Male athletes can just create their own bathroom." David Madison/Getty Images

It's a gift they don't always use responsibly. Plagued by blisters on his pitching hand in 2016, the Dodgers' Rich Hill peed on his fingers. It's an old-school remedy that dates back to former major leaguers Moises Alou and Jorge Posada, who didn't use batting gloves because they believed trace amounts of urea in their urine toughened their skin. (Urea is a common ingredient in commercial moisturizing creams.) Posada used to warn, "You don't want to shake my hand during spring training."

Some sports do take a more palatable and humane approach to the act of urination, but proper facilities and protocols are still no match against millions of dollars in prize money. At grand slam tennis events, men are permitted two potty breaks during five-set matches; women get two for three-set matches. On the matter of urination, the rules read like a junior high student handbook, allowing competitors to "leave the court for a reasonable time for a toilet break," while falling just short of asking Roger Federer to put the seat down when finished.

Since the potty provision's inception, however, tennis players have been exploiting the pee-break rule for strategic advantage, proving there is no level elite athletes will not stoop, or squat, to in order to gain the slightest advantage. In the 2010 Australian Open, after losing the first set of his quarterfinal match, Federer killed time in the can while allowing the blinding sun to dip below the stands. In 2012, Andy Murray won the first two sets of his U.S. Open finals match, but when the next two slipped away, he sheepishly signaled to the umpire and tiptoed off the court, disappearing into a one-toilet restroom under Arthur Ashe Stadium. As the crowd and Novak Djokovic waited, Murray later told The New York Times, he stood alone in front of the mirror screaming at his reflection, "You are not going to let this one slip." He was speaking of the match (one presumes), which he battled back to win after one of the most fortuitous pee breaks in sports history.

Whether it's a feint or a full flow, bathroom breaks such as Murray's can make all the difference in becoming a champion."This happens much more than fans would ever realize," says renowned boxing trainer Freddie Roach. "Knowing how an athlete's brain works, if all you can think about is needing to take a piss, that's gonna get you knocked out, or worse. So if finding a way to take a leak means helping you win, any trainer or any athlete in any sport would do the same thing."

You might say Roach learned this lesson firsthand while training James Toney for his 2003 fight against Evander Holyfield. Boxing's golden rule is clear: Never put the gloves on early before a big fight. Once they're secure and the tape is initialed by a boxing commission official, they can't come off. After that, if a fighter is overcome by the combination of prefight hydration and jitters, his entourage has to play a high-stakes game of "not it."

Moments before he was supposed to be in the ring, Toney turned to Roach with a look on his face every trainer dreads. (He's gotten the same look from Manny Pacquiao a few times in recent years.) With Holyfield waiting and the Mandalay Bay crowd growing louder and more restless by the second, Roach, out of options, shimmied his hand up the left side of Toney's black silk boxing trunks. (Roach went left because the names of Toney's children were stitched on the right side of his trunks.) Why he went up the shorts instead of down is simple: He's a damn pro. "Best way to do it," he says, "pull the cup out, pull the junk down, look the other way."

When boxer and trainer sheepishly exited the bathroom, Roach figured the incident was mercifully over. Heading to the ring, though, Toney blurted out, "Oh, Fred, that was so good; you were so gentle." Loose, unencumbered and 14 to 18 ounces lighter, Toney survived a sluggish start and a brutal shot to the kidneys at the end of Round 1 before pummeling Holyfield into submission in the ninth.

To this day, every time Toney sees Roach, he reminds him, loudly, about their Mandalay moment. Roach always grumbles back the same thing he said that night as Toney leaned toward the urinal. "Damn it, James, I don't even like holding my own."

Sooner or later, though, everyone-players, coaches, even trainers-must come to grips with the most unstoppable force in sports. "No one has to tell me about the importance of pee breaks in sports," Roach says. "S---, I haven't heard the end of it yet."