When women and girls don’t eat enough to fuel their workouts, their sport and long-term health can suffer.

A group of women jog outdoors.

It started innocently enough.

Nan Zhu, a 14-year-old high school freshman at the time, signed up for the school’s crew team and wanted to perform her best. At 5 feet 3 inches small ? “I wasn’t really built to be a rower,” she says ? Zhu felt she had to work harder than her more height-gifted teammates. So she gave it her all during practice and started learning about healthy eating for the first time.

“I really wanted to train to just be good and be on the team and do well,” says Zhu, now a 24-year-old medical student at the University of Rochester School of Medicine and Dentistry in New York.

Then, it got out of hand.

In?addition to training two hours each weekday with the team, Zhu also clocked at least two hours of exercise nightly on her own, running or hitting the gym after finishing her homework.?She turned down invitations?to the mall or amusement park because she worried she wouldn’t have enough time to work out.

Zhu’s?food rules were just as rigid.?Instead of eating healthfully most of the time, she?ate healthfully all of the time, never surpassing the recommended?serving size of?baby carrots, for instance,?or even?tasting?her own baked goods. She?avoided social situations like going to dinner and a movie because deciding what to order was too nerve-wracking. “My friends noticed?I became really withdrawn,” she says.

For about?two years,?she?stuck to the?regimen,?dropping to a low of 85 pounds?and losing her period. Her hair thinned and her?skin dried out. “None of those things were really that concerning to me,” she says. But then Zhu started?experiencing increasingly frequent?quad and hamstring cramps?that compromised her athletic performance.

“Sometimes they would be so severe I wouldn?t be able to walk; it was just so tight and painful. At that point, I started to realize that maybe this was too much, and clearly I wasn’t fueling my body enough,” she says. “That’s when I started thinking maybe I need to get help.”

A Triple Threat

Zhu’s internist eventually told her she had female athlete triad, a condition that?usually consists of three interrelated symptoms in active girls and?women: not eating enough (whether intentionally or not), menstrual changes and?weak bones, according to the Female Athlete Triad Coalition, an international?nonprofit that?promotes?health and well-being among active girls and women.?Though the three prongs of the condition often coexist, women?and girls?can still have female athlete triad if they only have one or two, says Dr. Elizabeth Joy?, a sports medicine physician in Salt Lake City and president of the coalition. “Each of these conditions is on a spectrum, and having one ought to prompt investigation for the others,” she says.

Boys and men who don’t eat enough to fuel their activity may?also suffer from a similar syndrome, but there’s not enough research yet to confirm it. While some professionals have proposed the term “relative energy deficiency in sport,” or RED-S, to describe the condition in?both genders, others say?changing the name of?female athlete triad after more than 30 years of research on it?would be a step backward for female athletes?.

It’s unclear how many women suffer from ?the triad, but one study found that 4.3 percent of female athletes had all three components of it?and anywhere from 5.4 percent to 26.6 percent had two.??The condition may be?on the rise as more?women and girls participate in sports?? 3.37 million in 2010 compared to only 310,000 before Title IX?gave women and girls equal access to federally-funded education programs and activities in 1972?? according to a? 2015 study in the Journal of the American Academy of Orthopaedic Surgeons.

The syndrome is particularly common among girls and women who participate in sports that value a lean physique, such as cross-country, gymnastics and ice?skating. “They think, ‘The lighter I am, the better runner I’ll be’ or ‘the better gymnast I’ll be,’ and then they end up getting injured,” says Nancy Clark?, a sports nutritionist in Newton Highlands, Massachusetts, who sees women with the condition daily.

That was Alyssa Burns’? thought process as a 15-year-old competitive gymnast in Long Island, New York.?Although she was already thin, she thought being thinner would give her a leg up on the competition.?”You’re flying through the air, and so it’s easier if you’re small,” says Burns, now a 22-year-old aspiring registered dietitian.?”I decided that in order to win, I needed to lose weight.”

But that didn’t work. Instead of winning or losing much weight, Burns lost the energy she needed to keep her head in the game. “I would freak myself out doing things,” she says. “[My teammates] knew something was wrong.”

More than just hurting sports performance, the female athlete triad seems to contribute to issues with fertility?and bone health even long after women recover, says Mary Jane De Souza?, a professor of kinesiology and physiology at Pennsylvania State University who studies the condition.

“That’s the big concern: Can we reverse bone health problems? We’re not 100 percent confident that that can happen,” she says. “And that’s why it’s a big deal because these women will enter the menopause years at a much lower bone density and precipitously become at risk for osteoporosis sooner than the average woman.”

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