Bonnie Bernstein, after working as an ESPN reporter at last fall's Oklahoma-Texas football game, joined her colleagues in running through the Texas state fair following the usual "escape plan" that TV crews make to catch their flights out of town.

Suddenly, she says, her "entire left leg felt shot," she was short of breath and thinking "none of that should have been happening. And I was in excruciating pain on my flight."

After all, she exercises regularly, neither smokes nor drinks and, she says, is "as vice-free as they come, outside of pizza and cheesecake."

But Bernstein, who last year joined ESPN after being a sideline reporter for CBS, ended up in a hospital with a hugely swollen knee, diagnosed with potentially life-threatening "deep-vein thrombosis," also known as blood clots. She began giving herself twice-daily injections of blood thinners but considered herself lucky: She'd suffered from exactly what had killed NBC News reporter David Bloom while with U.S. troops in Iraq.

Bernstein has learned what might have led to her condition — frequent flying, using estrogen-based birth control, a family history of clots — and now elevates her legs flying. That doesn't always help: "I thought my leg was going to explode on the flight back from the Pro Bowl in Hawaii."

Bernstein will appear in public-service TV for an awareness campaign from the Coalition to Prevent DVT. And she has a new take on the adage that what doesn't kill you makes you stronger: "I used to just say that figuratively."