Vicki Barclay was feeling off. The PhD, 34, a research scientist and mountain bike racer for Stan’s Notubes Elite Women’s team recalls that “for about a week I just didn’t feel right. I felt like I had bad indigestion and discomfort on my left side.”

It never occurred to her that it could be a serious blood clotting condition, called Deep Vein Thrombosis; instead, she chalked it up to previous injuries, travel and stress. But then, things got much worse. “I raced that Saturday and had a pounding headache.

I tried to ride the next day and was insanely breathless. Then I drove ten hours to do a ride I’d planned in Pisgah, North Carolina, but I was so weak I couldn’t even get on my bike. I ended up blacking out and going to the hospital.”

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The diagnosis was multiple blood clots (pulmonary emboli) in her lungs and a large clot (deep vein thrombosis) in her right leg. Barclay was admitted to the hospital, put on blood thinners and forbidden from mountain biking for the foreseeable future. “I can’t believe it happened to me. I should recover, albeit with a few bits of dead lung, but I went from easily completing multiple workouts a day to struggling to walk without help. The lesson I learned from this experience is not to always push through pain; sometimes stopping and listening to your body can save your life.”

So can knowledge of your risks, adds Barclay, which she wants more riders—especially women—to have.

Selene Yeager