Endurance athletes have their 'limit'
The death of Tom Lyons after finishing the Goondiwindi Hell of the West triathlon prompts a warning of the "risk of causing organic damage" if athletes have a medical condition, are dehydrated or not prepared.PT0M0S 620 349
The Hell of the West is considered one of Australia’s toughest triathlons.
The fittest of the fit and the extremely competitive converge on the tiny outback Queensland town of Goondiwindi amid the January heat to test their limits over a two kilometre swim, 80 kilometre bike ride and 20 kilometre run.
Tom Lyons, 21, collapsed and suddenly died soon after completing the Hell of the West triathlon at the weekend.
Tom Lyons collapsed after crossing the finish line of the Hell of the West triathlon. Photo: Facebook.
His shocked family says there were no obvious clues to explain his death - he ended the race smiling, even high-fiving a spectator before crossing the finish line.
The cause of Lyons’ death is yet to be determined, with an autopsy due in Brisbane this week.
While benefits of exercise are well known, researchers suspect that there may be a point at which exertion becomes dangerous, says Sports Medicine Queensland chief executive Mark Brown.
‘‘There’s only so much the human body can withstand,’’ he said.
‘‘People who go for a very long time, at a high intensity are always at risk of causing organic damage and potentially catastrophically so.’’
The death rate for triathlons is about twice that of marathons because of increased intensity of the competition, according to a 2012 study published in the journal Mayo Clinic Proceedings.
In fact, the swimming leg of a triathlon is considered the most deadly, because competitors can hyperventilate just as their body tries to slow down their heart rate to conserve oxygen in the water.
Normally the two responses don’t happen at the same time, but when they do, the heart can go into abnormal rhythms, which can cause sudden cardiac death.
Extreme heat can also be a deadly factor, Brown says. Competitors raced in 34.4 degree heat in Goondiwindi on Sunday.
‘‘The hotter it is, the more you sweat and the more you lose ions from your body. If you do not replace those electrolytes then eventually you can have a disturbance in the electrical activity of the heart,’’ Brown says.
A highly motivated athlete accustomed to pushing physical limits and failing to heed crucial warning signals, can also succumb to heat stroke, which can be life-threatening.
However, doctors attribute most recent triathlon deaths to pre-existing - and often undiagnosed - heart conditions.
Hypertrophic cardiomyopathy, a thickening of the heart’s ventricles, is often attributed to deaths in young athletes.
The thickening of the heart muscle can make it harder for blood to leave the heart and also for the heart to relax and fill with blood. The resulting arrhythmia can lead to cardic arrest.
But, the first symptom of hypertrophic cardiomyopathy is usually sudden collapse and death.
Researchers have also speculated that sprinting to the finish produces a rush of adrenalin that may trigger an abnormal rhythm in competitors with susceptible hearts.
That has prompted the International Federation of Association Football, as well as other sporting organisations, to recommend young athletes be screened for cardiac risk factors, via a medical examination, electrocardiogram (ECG) and ultrasound.
Sports Medicine Australia recommends that anyone preparing to participate in ‘‘unaccustomed or extreme sport, or form of physical activity’’, should seek a medical clearance.
Those guidelines typically apply for competitors over the age of 40, but are also relevant for younger athletes, who may have experienced light-headedness, fainting or shortness of breath during exercise, Mr Brown said.
Unfortunately, the practicalities of such testing are limited and the costs are prohibitive. There is also disagreement about the best strategy for testing.
Lyons was no stranger to high-intensity sports, having captained his school’s first XV rugby union squad and first XI cricket team and participated in lengthy charity races.
His family now waits for answers as to why the high-achieving sports enthusiast died in the prime of his youth.