Pro triathlete Danielle Mack is sharing her frustrating path to receiving a proper diagnosis for her exercise-induced breathing issues with The Washington Post.

Pro triathlete Danielle Mack is sharing her frustrating path to receiving a proper diagnosis for her exercise-induced breathing issues with The Washington Post. After several failed attempts at trying to find a solution to her ongoing pain, Mack was diagnosed with exercise-induced laryngeal obstruction, or EILO. The physician cited in the article says that the condition is more common than people realize—five percent of adolescents and young adults deal with it. Before being properly diagnosed, many—like Mack—are given medicine (often used to treat asthma) that can actually make the condition worse. The best treatment plan? Teaching the patient to employ a very specific breathing technique.

In two years, professional tri­athlete Danielle Mack saw 18 different physicians: family doctors, gastroenterologists, neurologists, allergists, pulmonologists and specialists of other sorts. She had many tests, but she got no explanations for what she called her “invisible illness.”

Mack’s symptoms included numbness in her legs, lightheadedness, dizziness, shortness of breath, chest pain, nausea and full-body cramps. The signs suggested exercise-induced asthma. Her physicians treated her with an inhaler, which not only did not work but also made her feel worse. Finally, Mack, who lives in Boulder, Colo., tried a stress test at National Jewish Health Hospital in Denver.

Under the supervision of pediatric pulmonologist Tod Olin, Mack rode a stationary bike while a tiny camera, inserted through her nose, filmed her vocal cords. As she increased her pace, the cords narrowed, blocking air. The result: a repeat of the symptoms she had been experiencing while training and racing. Olin diagnosed her in September with exercise-induced laryngeal obstruction, or EILO.

Exercise-induced respiratory symptoms are fairly common in adolescents and young adults (Mack is 30 years old), and the most likely explanation is asthma. A condition that has been recognized since the early 1980s, EILO is often missed by physicians, Olin said.

“Without intending to, patients often mislead doctors by unconsciously using the word ‘wheezing,’ which causes confusion,” Olin said. “If patients were to act out symptoms, the physicians could make a more accurate diagnosis, but that’s generally not part of the routine screening.”

Read more: Washingtonpost.com