(NECN) - Several days after the Boston Marathon, nine runners were still in the hospital in critical condition.
It was all in direct result of racing in the record heat.
The unusally warm weather sent 215 athletes to local hospitals, and more than 400 were treated and released from Red Cross tents.
One runner suffered a heart attack, and at least one other runner suffered heat stroke.
Dr. Annemieke Atema joined "The Morning Show" to discuss the threat of running in the heat.
Watch the attached video for more.