University of Wisconsin professor Daniel Eimermann died while competing in a triathlon in Devil's Lake State Park Saturday morning.

Devil's Lake State Park Superintendent Steve Schmelzer said some of the other competitors noticed Eimermann moving slowly and asked if he was OK, to which he replied positively.

Local lifeguards approached Eimermann shortly after and found him unconscious.

"They brought him to shore, and I believe he still had a faint pulse and shallow breathing," Schmelzer said. "But suddenly [he] stopped breathing."

Eimermann, a volunteer clinical professor in the UW School of Medicine and Public Health, was pronounced dead at a Baraboo hospital only a short time after. An autopsy has been scheduled, Schmelzer said.

According to close friends, the 55-year-old professor was in good shape and frequently participated in the Devil's Challenge Triathlon, an annual competition that takes place in Baraboo, Wis., according to the Associated Press.

Schmelzer said that another man found problems finishing the swimming part of the triathlon, but the professor's death was an isolated incident.

"He was a pretty frequent competitor and had constant training," Schmelzer said. "He looked like he was a pretty fit individual."

This marked the second death at Devils' Lake this year, according to The Associated Press.

In addition to his work at UW, Eimermann was a private practice Madison psychiatrist.

UW psychiatry professor Stephen Weiler said Eimermann was a great professional who cared for a large number of patients.

"His students will surely miss him and be disappointed by this loss," Weiler said.

He also said close friends and colleagues were all stunned and overwhelmed to hear about this loss.

"He died doing what he loved to do, which was exercising and competing," Weiler said. "It's a lesson of living every moment."

Laurie Jacobson, a psychiatric services operations manager, said the staff who worked with Jacobson is shocked.

"We are still trying to process what happened," Jacobson said, according to the Associated Press. "He was a very wonderful person, an avid runner and triathlon participant who exercised daily."