Race Safety and Medical Emergencies

Of the sudden deaths and cardiac arrests, 90 happened in the swim, far more than on the bike or run.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

85% of the 135 cases were men.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

The mean age was 46.7 years, so middle-aged men made up much of the risk.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

The study reported 1.74 fatal events per 100,000 participants over 2006-2015.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

Clinically silent cardiovascular disease was present in an unexpected proportion of those who died.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

A swimmer in trouble can slip under unnoticed in a crowd, and rescuers need time to reach them and start resuscitation.

Source: Endurance-event medicine reference · applied

Risk increased with age and was highest in older men.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

The authors concluded that death and cardiac arrest during triathlon are not rare and deserve prevention efforts.

Source: Harris et al., Annals of Internal Medicine 2017 (US triathlon deaths and cardiac arrests, 1985-2016) · recall

Middle-aged men with risk factors carry most of the risk, so a pre-participation medical review is sensible.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · applied

Spreading swimmers out lowers congestion, contact and panic in the first minutes, where many problems begin.

Source: Endurance-event medicine reference · recall

The rules tell an athlete in an emergency to raise an arm overhead and call for assistance.

Source: World Triathlon Competition Rules (18 January 2025), 4.1 · recall

Once official assistance is rendered in the swim, the athlete must retire from the competition.

Source: World Triathlon Competition Rules (18 January 2025), 4.1 · recall

Standing on the bottom or holding an inanimate object to rest is allowed; using it to progress is forbidden.

Source: World Triathlon Competition Rules (18 January 2025), 4.1 · recall

Someone drowning is usually struggling to breathe, so they cannot call out or wave; it looks quiet, not dramatic.

Source: Endurance-event medicine reference · recall

SIPE is fluid in the lungs during swimming, causing breathlessness, cough and sometimes frothy or blood-tinged sputum.

Source: Endurance-event medicine reference · recall

Cold water, a constricting wetsuit, high blood pressure and heavy pre-race drinking all raise the pressure in the lung vessels.

Source: Endurance-event medicine reference · recall

Suspected SIPE is an emergency: exit the water, sit upright, and get medical care and oxygen.

Source: Endurance-event medicine reference · applied

SIPE recurs in a substantial share of people, so a medical review is needed before open-water racing again.

Source: Endurance-event medicine reference · recall

Water safety crews are positioned to see distress early and reach a swimmer within seconds.

Source: Endurance-event medicine reference · recall

Matching swim-exit records to starters confirms everyone has left the water, so a missing swimmer is searched for at once.

Source: Endurance-event medicine reference · recall

Exertional chest pain, fainting, unexplained breathlessness or palpitations are warning signs needing assessment before racing.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Over about 35, coronary artery disease dominates; inherited conditions are the main cause in younger athletes.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

In younger athletes, inherited cardiomyopathies and electrical disorders are the leading causes.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Unexplained sudden death of a close relative at a young age can point to an inherited heart condition.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

European cardiology bodies support ECG screening of athletes; US bodies do not recommend it routinely, citing false positives and cost.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Decades of endurance training, particularly in men, are associated with a higher rate of atrial fibrillation.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Training enlarges the heart chambers and slows the resting heart rate; these are normal adaptations, though they must be told apart from disease.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Viral infections can inflame the heart muscle (myocarditis), and intense exercise during the illness increases that risk.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Palpitations with dizziness can signal a dangerous rhythm, so the athlete stops and seeks medical help.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · applied

The finding is real, but whether this calcified plaque carries the same risk as in non-athletes is still debated.

Source: Sports cardiology reference (ESC / AHA athlete guidance) · recall

Exertional heat stroke combines a core temperature usually above 40 °C with central nervous system dysfunction.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Cooling usually stops around 38.9 °C to avoid overshooting into hypothermia.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Oral, ear and skin readings are unreliable after exercise; rectal temperature is the field standard.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Immersing the body in cold or iced water cools fastest and is the gold-standard treatment.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Delaying cooling for transport costs time at high temperature; cooling on site first is what saves lives.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Rapid on-site cooling makes survival near universal; delay is what makes heat stroke deadly.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Antipyretics lower a raised set point in infection; in heat stroke the set point is normal and heat production overwhelms loss.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

Rotating towels soaked in iced water over the body and head is a practical second choice when immersion is not possible.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · recall

WBGT is read at the finish area every 30 minutes from three hours before the start, in direct sun 1.5 m above ground.

Source: World Triathlon Competition Rules (18 January 2025), 10.3 · recall

Wet-bulb globe temperature blends air temperature with humidity, radiant heat and airflow, which is why it tracks heat stress.

Source: World Triathlon Competition Rules (18 January 2025), 10.3 · recall

It is a blood sodium below 135 mmol/L during or up to 24 hours after exercise.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Weight gain during a race means fluid intake exceeded losses, the main setting for hyponatraemia.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · applied

As sodium falls, brain swelling causes confusion, seizures and coma, which is a medical emergency.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Severe cases get a small bolus of hypertonic saline; normal saline and extra water can worsen it.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Hyponatraemia and heat illness or dehydration can look alike, but giving fluids to a hyponatraemic athlete is harmful.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · applied

Long race times with generous drinking give the most opportunity to take in more fluid than is lost.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Non-osmotic ADH release during exercise limits water excretion, so excess drinking dilutes the blood.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

It can appear during exercise or in the day afterwards, especially if heavy drinking continues after the finish.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

On average lower body mass and longer times mean a given drinking pattern dilutes sodium more.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Non-steroidal anti-inflammatory drugs have been associated with hyponatraemia in some studies, though not consistently.

Source: Exercise-associated hyponatraemia consensus (Hew-Butler et al., 2015) · recall

Most finish-line collapses are a drop in blood pressure on stopping, which is benign when recognised.

Source: Endurance-event medicine reference · recall

Leg muscles pump blood back to the heart while running; stopping suddenly lets blood pool, so pressure drops.

Source: Endurance-event medicine reference · recall

Lying flat with the legs and pelvis elevated restores blood to the heart and brain.

Source: Endurance-event medicine reference · recall

With legs raised, recovery is usually quick; failure to improve is a sign to look for another cause.

Source: Endurance-event medicine reference · recall

Collapsing while still racing is not explained by stopping, so cardiac, heat or sodium causes must be ruled out.

Source: Endurance-event medicine reference · applied

Unresponsive with abnormal breathing means cardiac arrest until proven otherwise: CPR and a defibrillator immediately.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · applied

Confusion plus heat suggests heat stroke, which needs a rectal temperature and immediate cooling.

Source: Exertional heat illness consensus (ACSM and sports-medicine guidance) · applied

Heat stroke, hyponatraemia and low blood sugar each need different urgent treatment.

Source: Endurance-event medicine reference · recall

An alert athlete with low glucose is treated with fast sugar by mouth; if not alert, medical staff give it another way.

Source: Endurance-event medicine reference · applied

Discharge is a medical decision, taken once the athlete is assessed as safe to go.

Source: Endurance-event medicine reference · recall

Any suspicion of concussion means stopping; it is not a decision to make on the athlete's own feeling.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

Consensus guidance rules out same-day return after a suspected concussion.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

Return follows graded stages, usually at least 24 hours each, moving on only if symptoms do not return.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

Red flags such as a worsening headache, repeated vomiting, seizure or deteriorating consciousness need emergency care.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

With possible spinal injury the head and neck are kept still and the helmet left on until trained help arrives.

Source: Endurance-event medicine reference · applied

Helmet foam is designed to crush once; damage may be invisible, so it is replaced after an impact.

Source: Endurance-event medicine reference · recall

The expanded foam compresses on impact, spreading and absorbing energy that would otherwise reach the brain.

Source: Endurance-event medicine reference · recall

Falling onto the shoulder or hand transmits force to the clavicle, the classic cycling fracture.

Source: Endurance-event medicine reference · recall

Symptoms can develop over hours, so a rider who seemed fine is still watched after a head knock.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

Most concussions happen without loss of consciousness, which is why milder signs must be taken seriously.

Source: Concussion in Sport Group consensus (Amsterdam 2022) · recall

Cold shock passes in about a minute, useful muscle function lasts roughly ten, and hypothermic unconsciousness takes about an hour.

Source: Cold-water immersion and sea-survival reference · recall

Muscles and nerves in the limbs cool first, so a swimmer loses the ability to swim before becoming hypothermic.

Source: Cold-water immersion and sea-survival reference · recall

The gasp and uncontrolled breathing of cold shock can lead to inhaling water within the first minute or two.

Source: Cold-water immersion and sea-survival reference · recall

Cold blood from the limbs returns to the core after rescue, so temperature can fall further for a time.

Source: Cold-water immersion and sea-survival reference · recall

Loss of water pressure on the body, lifting upright and relief can drop blood pressure just as the swimmer is rescued.

Source: Cold-water immersion and sea-survival reference · recall

Rough handling and sudden rewarming can trigger dangerous heart rhythms or collapse.

Source: Cold-water immersion and sea-survival reference · recall

Warm, sweet drinks help an alert athlete; drowsy or confused athletes are not given anything by mouth.

Source: Cold-water immersion and sea-survival reference · recall

Removing wet layers, insulating and sheltering stop further heat loss before active warming.

Source: Cold-water immersion and sea-survival reference · recall

The neoprene slows heat loss and keeps the body afloat, buying time, but it does not remove cold shock.

Source: Cold-water immersion and sea-survival reference · recall

Fat is an insulator, so lean athletes lose heat faster and need more protection in cold water.

Source: Cold-water immersion and sea-survival reference · recall

Check whether they respond and breathe normally, and call the emergency services and for an AED.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Agonal gasps are common in the first minutes of cardiac arrest and must not be mistaken for breathing.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · applied

Guidelines call for 100-120 compressions per minute.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Compressions should push the chest down about 5-6 cm and let it recoil fully.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Hands go in the centre of the chest on the lower half of the sternum.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Hands-only CPR is recommended for untrained rescuers; trained rescuers use 30 compressions to 2 breaths.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

AEDs are designed for lay use: they analyse the rhythm and shock only when needed.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Pads need dry skin, and the patient should be moved out of standing water; the delay should be brief.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · applied

Every minute without CPR or a shock cuts survival by around 7-10%, which is why bystanders act at once.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Fatigue makes compressions shallower within minutes, so swapping keeps them effective.

Source: Resuscitation guidelines (European Resuscitation Council / AHA) · recall

Any athlete who appears to officials or medical personnel as presenting a danger may be removed from the race.

Source: World Triathlon Competition Rules (18 January 2025), 6.3 · recall

Medical guidelines, including hot-weather guidelines and evacuation plans, come from the race medical director and the medical delegate.

Source: World Triathlon Competition Rules (18 January 2025), 15.1 · recall

Withdrawing athletes must tell a technical official, so no one is searching for a missing athlete.

Source: World Triathlon Competition Rules (18 January 2025), 2.1 · recall

Conditions, medicines and an emergency contact help medical teams treat an athlete who cannot speak for themselves.

Source: Endurance-event medicine reference · recall

The WBGT thresholds for modifying competition for healthy adults follow ACSM's 2007 recommendations.

Source: World Triathlon Competition Rules (18 January 2025), 10.3 · recall

Decisions consider medical facilities, the weather forecast, season, distance, category, athlete fitness and age.

Source: World Triathlon Competition Rules (18 January 2025), 10.3 · applied

Unacclimatised or less-trained participants are at higher risk of heat illness when heat arrives unexpectedly.

Source: World Triathlon Competition Rules (18 January 2025), 10.3 · recall

Triage makes sure a collapsed, confused athlete is seen before one with blisters.

Source: Endurance-event medicine reference · recall

The responsibility for remaining on the course rests with the athlete.

Source: World Triathlon Competition Rules (18 January 2025), 6.3 · recall

It sets how injured or ill athletes are reached, moved and handed to hospital care from every part of the course.

Source: Endurance-event medicine reference · recall