Review updated cardiology guidance for older adults training for marathons and Hyrox races, including essential medical screening checks and warning signs.
The Singapore Heart Foundation cites approximately 3,000 out-of-hospital cardiac arrests in Singapore each year, with a survival rate of 25.9%. This single metric illustrates a stark reality for the aging endurance community. It proves that unseen vulnerabilities can exist regardless of external physical appearance.
On August 30, 2026, Channel NewsAsia published fresh medical guidance from leading cardiologists regarding cardiovascular screening for adults. This advice specifically targeted athletes preparing for marathons and high intensity hybrid events like Hyrox. The medical community provided this updated framework following a recent tragedy in the fitness space. Channel NewsAsia reported that 41-year-old fitness coach Leroy Saunders collapsed during BYD HYROX Bangkok 2026 on August 13 and later died in hospital.
While his family has not publicly disclosed the cause of death, the incident has prompted a vital conversation about pre-participation health checks. Saunders was a South Africa-born CrossFit gym owner in Bangkok who had competed in previous Hyrox races. His prior competition history illustrates why visible fitness cannot be treated as proof that an athlete has no underlying cardiovascular risk. Cardiologist Dr Bharat Vashdev Khialani told Channel NewsAsia that cardiac events occur during endurance activities like marathons, triathlons and cycling races.
The core finding from this updated guidance is that performance capacity and cardiovascular health are two entirely different physiological states. Many athletes mistakenly believe that a high VO2 max serves as a blanket medical clearance for extreme exertion. Khai Jamilson, lead sport and exercise scientist at UFit, explained that VO2 max testing simply measures how effectively the lungs, heart and muscles use oxygen during exercise.
The VO2 max test generally involves exercise on a treadmill or bike. A mask and metabolic analyzer measure oxygen intake and carbon-dioxide production breath by breath. The workload progressively increases through faster speed, greater incline or higher bike resistance until the athlete reaches voluntary exhaustion. Adult men typically see reference ranges of approximately 35 to 45 millilitres of oxygen per kilogram per minute.
Adult women generally score between 28 to 38 ml/kg/min, while highly trained individuals routinely record substantially higher values. However, Dr Khialani stresses that a high VO2 max demonstrates physical performance capacity but does not exclude underlying heart disease. A strong aerobic engine means very little if the structural integrity of the heart is compromised by undetected plaque or electrical abnormalities. To establish genuine medical clearance, athletes must look beyond performance tests.
The fundamental checks discussed by Channel NewsAsia include maintaining blood pressure ideally below 130/85 mmHg and keeping LDL cholesterol below 2.6 mmol/L. A resting ECG within the stated reference range of 60 to 100 beats per minute is another baseline metric. However, clinicians note that higher-risk individuals may require substantially lower targets. When appropriate, cardiologists can deploy advanced diagnostics like an echocardiogram or a treadmill stress test.
An echocardiogram evaluates heart structure and pumping function, while coronary CT tests can assess calcium deposits, plaque burden or narrowing in the coronary arteries. A Holter monitor may be worn for 24 to 48 hours or longer to detect rhythm disturbances that may not appear during a standard resting ECG. Dr Khialani cautioned that these advanced imaging tools should be selected according to the athlete's age, symptoms, family history or cardiovascular risk factors. General practitioners can help decide which specific tests are appropriate rather than sending every runner directly for advanced imaging.
Understanding the specific physiological demands of your chosen event is crucial for accurate risk assessment. A marathon creates a steady, prolonged cardiovascular demand over several hours. In contrast, Hyrox combines 1-kilometre runs with functional stations such as sled pushes and burpee broad jumps. The official event format involves approximately 8 kilometres of running spread across roughly 90 minutes, repeating the sequence eight times.
Dr Khialani stated clearly that neither a marathon nor a Hyrox event should automatically be labeled more dangerous than the other. Risk always depends on individual fitness, underlying medical conditions and preparation for the specific event. Bervin Manoharan, co-founder and general manager of Catalyst Performance, observed that athletes can underestimate Hyrox because the individual strength movements are highly familiar. The true physical challenge lies in performing heavy sled pushes or wall balls while already fatigued and operating with a rapidly rising heart rate.
Hyrox continues to attract participants who may be comfortable with individual components but lack experience with combining them under accumulated fatigue. The principal preparation gap is not necessarily learning the functional movements themselves. Instead, the gap is developing the aerobic base and recovery capacity needed to repeat them after sustained running. Manoharan noted that athletes are often limited by how quickly their heart rate rises and how slowly it recovers.
Proper preparation requires dedicated time and a strict emphasis on the aerobic engine. Manoharan recommends beginning race preparation 12 to 16 weeks before competition, spending most training time developing aerobic capacity rather than just focusing on the stations. Allocating time for structuring a long-term endurance plan ensures you build this crucial cardiovascular foundation safely. This measured approach prevents the sudden spikes in intensity that can overstress an unprepared cardiovascular system.
For ambitious adults aged 35 to 65, this cardiology guidance forces a fundamental shift in how we approach our training calendars. We can no longer rely on our athletic identity or previous race results to justify skipping medical evaluations. The article identifies older athletes, smokers and people with high cholesterol, high blood pressure or diabetes as groups needing structured medical assessment. Anyone with a family history of premature heart disease must also treat pre-participation screening as a strict requirement.
Dr Khialani advises athletes to seek an assessment several months before beginning a new endurance sport, substantially increasing training intensity or preparing for a first marathon. Starting early gives clinicians the necessary time to investigate abnormalities and address risk factors before the training volume reaches its absolute peak. Taking a clinical, objective approach to our bodies is a basic requirement for long-term athletic success.
When my Achilles flared up right before a major marathon build, the standard advice was total rest. But studying the clinical research on tendon loading changed my approach entirely. I swapped complete rest for heavy slow resistance training, specifically utilizing heavy calf raises on a deficit. It felt counterintuitive to load an injured tendon, but the science was clear.
Within six weeks, the morning stiffness faded, and I was back to building mileage without the chronic ache. That exact willingness to follow clinical science must apply to how we approach evaluating cardiovascular risk factors as we age. Veterans of the sport must memorize the definitive warning signs that dictate an immediate halt to any workout or race. Athletes must stop and seek urgent medical attention if they experience chest pain, unusual shortness of breath or dizziness.
Additional warning signs include faintness, palpitations, sudden extreme fatigue or collapse. These symptoms should never be dismissed simply because an athlete is accustomed to hard training. Knowing how to safely adjust your training loads during periods of fatigue is important, but ignoring acute cardiac symptoms is a mistake that ambition cannot fix. Some cardiovascular conditions remain completely silent until the heart is severely stressed by intense exercise.
True athletic durability requires accepting that a fast race time holds no value if the heart pacing the effort cannot safely carry you across the finish line.
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