Editor's note: Sheri Piers is a professional runner who came in as the second master's finisher and 20th woman overall in Monday's Boston Marathon. Last year, she was 10th overall and the first American to cross the finish line. She is a nurse practitioner and lives in Falmouth, Maine.
(CNN) -- I ran my eighth Boston Marathon on Monday, the day the bombs went off. We cannot let this terrible tragedy taint this amazing international event or let whoever was behind this evil act win. That's why I will run it again.
Marathoners are tough-minded and can endure discomfort for long periods of time. They enjoy running to push themselves and often run with others and make friends along the way. Some are highly competitive, like me, and enjoy the long, hard journey to get into marathon shape before the race.
After all that training, the Boston Marathon is usually a very happy day that results in a joyous sense of accomplishment. But today, most runners are probably feeling as I do: disgusted, saddened, angry and depressed.
The race feels surreal, almost as if it didn't happen, and as if a whole lot of training and hard work amounted to nothing. I don't think one participant can walk away from that marathon and feel glad. Most people say they want to forget it because of all the sadness and loss.
On the day of the marathon, I had set out to Hopkinton, Massachusetts, where the race begins, to start in the elite women's field, which begins 30 minutes ahead of the remaining waves.
As I was standing on the starting line and looking at the thousands of people around me, I was struck by a terrible and unusual thought: "Today's venue would be an opportune time for someone to hurt a lot of people." It passed, the gun went off, and I was on my way to Boston.
This was an especially exciting year because it was the first time my three children, who are 13, 11 and 10, came to watch mommy run the Boston race. As I concluded the race, the second master's finisher and 20th woman overall, I was immediately escorted back to the Fairmont Copley Hotel where my family and I were staying.
We were sitting around discussing the race, and the first explosion went off. Then the next. We all looked at each other wondering what that could have been -- with a gut-wrenching feeling, we realized it had to be bad. Sirens were wailing, and the streets were full of commotion.
Panicky texts were coming in fast from family and friends, asking if we were all safe, sending information about the two bombs that went off at the finish line. Our TV was turned off: Someone had told me to keep it off to spare the kids the gory details. The hotel went into lockdown for the next five hours, and our fear grew.
We couldn't help but think of all the people involved, the people who were killed and injured, their families, the volunteers, the first responders, the medical personnel and the runners. We wondered how race director Dave McGillivray was doing. He has the respect of the whole running community for all he has done to make the Boston Marathon so special and memorable for everyone involved.
My kids keep saying, "What kind of an idiot would do something like this? Who would do this? What do you think they are feeling about what they did right now? Are you scared to run the Boston Marathon again, Mommy?"
Runners will continue to participate in the Boston Marathon -- but it may take years for the fear to go away completely. I love running this marathon and will continue to do it. But next time I run down Boylston Street to the finish line, I will think of all the people injured and the ones who lost their lives for nothing. And I think my children have seen their mom run the Boston Marathon for the first and last time.
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The opinions expressed in this commentary are solely those of Sheri Piers