For Betty Cook, vice president of the Las Vegas Track Club, watching the events unfold in Boston on Monday was especially surreal.
Cook almost ran that marathon herself.
"I had planned on doing Boston this year and then I looked at my schedule and said it's going to be a little hectic," Cook told FOX5.
But many of Cook's friends and running partners went to run the Boston Marathon.
Much of Monday Cook was left with the anxiety of not knowing if those friends were injured or killed.
"That's the first thing I thought of is are they OK," Cook said.
It's a feeling shared by countless others in the running community in Southern Nevada.
"This is to marathon-ing what 9/11 was to air travel," said Tim Kelly, who organizes the Las Vegas Running Company, which trains runners for marathons.
Kelly said Monday's tragedy won't keep runners from traveling to other marathons across the country, but it will change the interaction between the runners and the crowd.
"It's for the volunteers, for the family members, for the friends, the spectators ... for them, this changes everything because they will be at a more removed distance now," Kelly said.
Meanwhile, Cook was relieved to get one of her running partners in Boston to finally reply to her text.
She said running the Boston Marathon is still something she'll one day do.
"It won't keep the running community down. We're too strong," Cook said.
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