David Reichman was taken to Coney Island Hospital where he was pronounced dead, after collapsing around 9 a.m. upon the 13.1 mile race.
"I cannot process this," one person wrote on a Facebook tribute by Chabad at Concordia. "David Reichman is one of the best."
A licensed clinical social worker and psychologist, Reichman graduated from New York University and founded Field Trip Health, a Kips Bay-based mental health and psychotherapy company, according to his LinkedIn page.
The temperature had reached 70 degrees with 83% humidity as of 9 a.m., Fox Weather says.
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