The preliminary autopsy on Doug Witmer failed to determine what killed the 42-year-old athlete during the swim portion of the High Cliff Triathlon on Saturday.

Similarly, efforts to pinpoint the cause of dozens of other deaths in the rapidly growing sport have returned inconclusive results. The demand for answers is likely to increase, with nearly 2.3 million people now participating in at least one triathlon each year, the number of races sanctioned by USA Triathlon growing to 4,334 and more than a half-dozen very public deaths annually.

Without question, research has shown the swim portion of the multi-discipline races is the most dangerous, with death rates twice those found in running marathons.

As one race organizer noted in a similar discussion in 2009 – when three triathletes died in Wisconsin races – if an athlete has a problem during the bike or the run leg of a triathlon, they stop. That’s often not an option in the water.

But the unanswered questions remain: Do athletes suffer panic attacks and drown? Do they suffer heart attacks? Do they simply exhaust themselves? What causes them to go under?

Dr. Kevin Harris, from the Minneapolis Heart Institute, analyzed 14 deaths in 2,846 triathlons across the country from January 2006 to September 2008, and all but one occurred in the water. Autopsies found that four of the victims had underlying cardiac disease.

Harris and others speculated that the cold water may contribute to irregular heart rhythms and that some athletes may be at greater risk due to a lack of training in open water.

In a much-discussed piece in the Washington Post, doctor and journalist David Brown analyzed the deaths of nine triathlon participants in 2011 and again found all but one occurred in the water. Brown theorized that the swimmers suffered panic attacks and drowned.

But he too has been unable to make his case with much certainty.

Brown offered this analysis in an interview with Slowtwitch.com: “There has been very little research on the cause of death of swimmers in triathlons other than the autopsies that are performed on nearly all the victims.

“The details of those autopsies are generally not available to the public although the one-sentence “manner and cause of death” generally is. In my opinion there needs to be some very basic epidemiology done about this problem. What is the sex, age, experience, training, co-existing medical conditions, medications used, etc. in these cases? As to my hypothesis that panic attacks underlie most of them, the first question that needs to be answered is how common panic attacks are among triathletes. This can only be determined by conducting statistically valid surveys.”

In the immediate case, the Appleton Post-Crescent suggested in a story Monday that the race organizers may have failed to provide adequate protection for the 1,300 participants who took to the water in Lake Winnebago. The story noted that three people have died during events organized by Midwest Sports Events since 2009.

Gloria West, executive director of the race promoter and a veteran triathlon organizer, told the Chicago Tribune that rescuers reached Witmer almost immediately after he started to struggle.

According to her account, Witmer had just begun the swim when lifeguards noticed him moving slowly in the water.
“They saw him take another four strokes, and he went down,” West said.

Lifeguards leaped to his rescue immediately, she said. They pulled him from the water and tried to revive him to no avail.

West said the lake was calm, and the weather was pleasant. Witmer didn’t appear to flail in the water, she said.

Additional tests will be conducted in the coming weeks to determine if Witmer suffered a heart attack or similar problem that caused him to go under, according to Regina Behnke, deputy coroner in Calumet County.
The Calumet County Sheriff’s Department is leading the investigation into the death and will review the onsite emergency response, according to Chief Deputy Brett Bowe,