Doctor Warns HYROX Athletes After Cardiac Arrest Incident

Bangkok — A sports cardiologist has urged HYROX competitors to heed warning signs from their bodies and stop immediately if they experience chest pain, unusual shortness of breath, or dizziness, following reports of an athlete suffering cardiac arrest during the event.

The warning came after social media posts showed a HYROX competitor receiving CPR before being taken to hospital.

Dr. Akanit Srisukwattana, an internal medicine specialist in cardiology and sports cardiology, subsequently posted advice for HYROX participants on his Facebook page.

Addressing HYROX competitors, Dr. Akanit said there had been a report of an athlete suffering a heart attack during competition. He noted that the reported incidence of cardiac arrest during sports was about one in 100,000 people in the general population. For people aged 50 and over or those with underlying health conditions, however, the rate could be as high as one in 5,000.

There is currently insufficient data to establish whether HYROX carries a higher risk of death than running or other endurance sports. However, HYROX combines running with power-endurance exercises, which can cause heart rate and blood pressure to rise sharply at certain points. The physical demand can be greater than ordinary running or weight training, particularly during high-resistance stations such as Sled Push, Sled Pull, and Burpee Broad Jumps.

Dr. Akanit advised competitors to keep their effort in line with what they had trained for and avoid pushing for a faster time or working beyond their physical capacity. He particularly warned people with risk factors including high cholesterol, high blood pressure, diabetes, smoking history, or a history of cardiovascular disease, as these factors can increase the risk of plaque rupture and a sudden heart attack.

During competition, athletes should not feel they have to give maximum effort at every station. They should allow themselves periods to ease off and control their breathing, particularly during demanding stations, so that the heart has a chance to reduce its workload before they resume running.

For people at higher risk, Dr. Akanit recommended keeping most of their effort around RPE 7/10 — feeling tired but still in control and able to speak in short sentences. Periods of exertion at RPE 8–9/10, when an athlete is so exhausted that speaking is difficult, may occur during competition but should not be maintained for long periods.

He urged competitors to stop immediately and alert the event medical team if they experience chest tightness or pain, unusually severe shortness of breath compared with the level of exertion, dizziness or feeling faint, abnormal palpitations, or cold sweats.