There's little downtime for the dozen or so spellers who make it to the primetime finals of the Scripps National Spelling Bee.

Once they get through the morning finals, which can last 4 hours or more, the remaining spellers are swarmed by relatives, reporters — and Scripps representatives who hand them a color-coded schedule that maps out nearly every minute between their two sessions on stage.

The marathon final day is part of an exhilarating and exhausting week. This year's super-sized bee, starting Tuesday, has three full days of spelling because Scripps allowed wild cards into the field for the first time. How the 516 competitors manage stress could play a bigger role than ever in who wins.

By the time the ESPN-televised finals begin Thursday night, competitors are often physically and emotionally spent after days of having their routines thoroughly disrupted.

Many struggle to sleep. They don't get exercise. Their meal times are erratic. They spend hours sitting on a stage with nothing but their own minds for company. And their free time is often spent buzzing around the Washington-area convention center that hosts the bee, mingling with fellow competitors.

"You're in a hotel room, and your schedule is packed. It can definitely throw you off your rhythm," said 15-year-old Shourav Dasari of Spring, Texas, who finished fourth in last year's bee. "It's really easy to get thrown off your rhythm during bee week."

The bee is open to kids through eighth grade, and early adolescence is when the brain has some of its greatest capacity for learning, said Dr. Frances Jensen, chair of the neurology department of the University of Pennsylvania and the author of the best-selling "The Teenage Brain." But stress, lack of exercise and sleep deprivation have a stronger effect on cognitive function for adolescents than for adults.

"Sleep is really important for creating memories and consolidating memories, so if they are sleep-deprived, they're definitely not accessing the information as well as they could," Jensen said.

The past 13 champions and 18 of the past 22 have been Indian-American, and there's a good chance that run will continue. Many of the previous high finishers in this year's field have Indian heritage, and those spellers also have the opportunity to hone their craft in other highly competitive bees that are limited to kids of South Asian descent.

Shourav insists that stress and fatigue weren't the reasons he didn't win last year, as he was widely expected to do. But some past competitors wonder if being run down led them to misspell words.

"I missed a word that I had studied multiple times, and frankly I'm not sure whether being tired factored into that," said 16-year-old Mitchell Robson of Marblehead, Massachusetts, who finished seventh in 2016. "It definitely could have been a factor."

When Mitchell prepared at home, he'd break up the monotony by going outside to shoot hoops. Shourav would play tennis, or take a stroll. Thirteen-year-old Erin Howard of Huntsville, Alabama, a two-time finalist expected to contend this year, rides her bike during study breaks. Those options are absent during bee week.

"You're sitting on stage for so long, especially during the prelims, your legs fall asleep and you end up staggering to the microphone," Erin said.

Last year, spellers who made it through the morning finals didn't eat lunch until after 2:30 p.m. Erin, who finished seventh, said she wasn't hungry when dinnertime rolled around — but she forced herself to eat so she'd have energy for the long night.

Stuti Mishra didn't have that foresight. The 2012 runner-up didn't eat much when finalists got their only shot at a meal. She held herself together on stage, but nearly blacked out after she missed a word to fall short of the title.

"Your vision gets cloudy and a black cloud kind of overcomes you," said Mishra, who's now 20 and just finished her sophomore year at Princeton. "I couldn't see anything and I thought I was going to faint, and I think the reason I was going to faint is that I hadn't eaten dinner earlier."

The word she misspelled was one she'd studied.

"I do attribute that to, maybe I was too nervous, maybe it was because I didn't eat," she said. "I couldn't focus. I couldn't recall it."

Jensen, the neurologist, said skipping a meal is understandable because adolescents' frontal lobes, which govern decision-making, haven't finished developing.

"They don't have that experience, they don't have that causality built into them," she said. "In what they perceive as a high-stress situation, they're not going to have their frontal lobe saying, 'Calm down. You've done this.'"

___

Follow Ben Nuckols on Twitter at https://twitter.com/APBenNuckols