A triathlete’s guide to heart health: screening, symptoms, and the ‘athletic’ heart
We all know how important it is to look after our muscles, but what about the most important one of all – our heart? Here’s a comprehensive triathlete’s guide to keeping your ticker in check…
While we make a conscious effort not to pull a tight hamstring or strain a niggly calf as athletes, there’s another more important muscle in the body that we should treat with even greater care, but perhaps rarely consider: our heart.
Research shows that exercise is generally good for the heart, but most of us are aware that, while rare, there can also be occasional complications – with different considerations for triathletes of different ages, different fitness levels, and competing in different triathlon distances.
So, whether you’re an up and coming junior or novice in your late 50s, in this article we’ve shared our detailed research into the steps you should take to make sure you’re exercising safely, and to give you peace of mind that you can carry on enjoying your swim, bike and running with confidence for years to come.
“The headline is always that the benefits of exercise far outweigh the risks,” says professor Dan Augustine, a consultant sports cardiologist from Bath. “The caveat is that if you’re doing a high volume of exercise over a number of years, the heart can adapt, particularly in endurance sport.”
Augustine’s opening remark sums up the challenge of covering heart health as a topic. While we shouldn’t ignore the risks, we equally shouldn’t lose sight of the fact that some level of exercise is almost universally preferable to staying sedentary.
How widespread are heart issues? “The most recent data we have is from the Football Association,” Augustine explains. “They followed people for up to 20 years and found that approximately one in every 300 that they screened had a cardiac issue that could potentially cause harm.”
The potential issues
Researchers typically split cohorts into under and over 35s. Or younger and masters athletes, if you prefer. “The cause of sudden death in an under 35 is usually rhythm disturbances of the heart – electrical activity that goes awry and causes a collapse or cardiac arrest,” he explains.
“The next most common cause is a structural problem of the heart muscle; being thicker or not pumping as well as it should. If you are younger, it’s electrical problems or pump problems.”
Amateur triathletes over the age of 35 should consider different pathologies. “Our overall cardiac risk increases as we get older no matter how fit we are,” Augustine says. “Ninety percent of people dying of heart attacks will be in middle age or older.
“Take a view on your personal health first. Think about your age and your ethnicity. If you’re Asian, like me, your risk is probably a bit higher than if you were caucasian.
“If you have a family history of early heart attacks (under 60) or other risk factors for coronary artery disease such as being a smoker, having diabetes, having high blood pressure or high cholesterol levels, that puts you a bit more at risk too.”
Heart rhythm issues can increase as we age, with the most prevalent being atrial fibrillation (AF) where one of the chambers in the heart pumps more irregularly.
“There are studies that show if you have been an endurance athlete over a number of years your likelihood of having AF in your latter years – over 50 – is higher than the age-matched sedentary cohort,” Augustine says. “That risk is greater if you’re a man, and of bigger stature.”
As ever though it’s a mixed picture. Studies show that the people who exercise and have AF also have a lower chance of a stroke, probably because they’re more healthy in other areas such as blood pressure and cholesterol.
What are the benefits of screening?
The level of aerobic exercise where screening is recommended is surprisingly low under European guidelines – just three hours a week – which most active people fall into.
Screening starts with a questionnaire about your personal and family medical history to try and identify any ‘red flag’ scenarios.
Typically, the next step is an echocardiogram (ECG), which shows the electrical activity of the heart, and an ultrasound, which reveals the heart’s size, its pump function, and how effectively the valves work.
“The general European guidance would be to get screened once every two years,” Augustine adds. “If you’re an elite athlete, the general advice would be to do it annually, but it’s not cheap so if you’re an elite athlete without sponsorship you have to weigh it up.”
Free screening for the under-35s
Cardiac Risk in the Young (CRY) was established in 1995 to support young people diagnosed with potentially life-threatening cardiac conditions and offer bereavement support to families where young people die from a cardiac incident. It also facilitates screenings for under 35s and funds research.
“We’ve screened over 270,00 people,” explains chief executive Dr Steven Cox. “It’s back up to 27,000 [in the] year following covid and about 10% of those we screen are elite athletes such as Olympians, the other 90% are fit and healthy young people playing grassroots sport aged 14-35.”
There are two-to-three screenings each weekend around the country and booking a screening is straightforward through testmyheart.org.uk.
The challenge is keeping up with demand with a backlog of applicants following the pandemic. The limiting factor is the number of specialist cardiologists, but while training is ongoing, introducing artificial intelligence in the near future might allow for a more cost-effective solution.
Cox says of the one in 300 screenings where they do find an irregularity, it’s not a given that it will always cause a health issue. He stresses that early identification and treatment of a “hole in the heart or valve problem,” for example, could prevent someone presenting in a cardiology ward in their 50s with a critical condition.
“The message I’d give to young athletes is the sooner you get screened the better,” he explains. “In 25% of cases where we find a serious condition, we advise the individual to stop competing, but in 75% they can be treated and return.”
Is there screening available for the over-35s?
For those aged over 35, where do they turn? Once we hit 40, the first step is to take advantage of the free health check-up by the NHS where cholesterol levels and blood pressure will be checked.
“With that information, an expert in sports medicine or cardiology will be able to give you an idea of what your cardiovascular risk is over 10 years,” Augustine says. “If you’re low risk, then you’re probably going to be fine. If you’re moderate to high risk, which means a 10% risk of having a cardiac episode over 10 years, it needs to be addressed through a proper consultation.
“The caveat to all of this is don’t go from zero to 100 without being sensible and building it up slowly. The overwhelming message is: ‘Yes, exercise, but do it safely.’”
What are the symptoms of heart problems?
While screening is designed to pick up hidden symptoms, there can also be warning signs. “Feeling a bit light headed and wobbly after you’ve really pushed it isn’t that unusual,” Augustine says.
“But take note of chest pain on exertion, palpitations on exertion, episodes of altered consciousness, undue breathlessness or if your heart rate goes up disproportionately to the level of exercise you’re doing and stays high when you back off.
“The analogy I use for athletes who I’ve recommended to stop for a period is that if they’d had a calf pull they wouldn’t go sprinting down the road. The heart is the engine, and it’s important to look after it too.”
How do British Triathlon operate?
British Triathlon must meet World Triathlon requirements to ensure athletes are fit to compete, which include a clear cardiac screen that is signed off by a doctor once every two years.
For World Class Programme athletes, British Triathlon arranges and pays for an ECG once every two years. Athletes representing Great Britain at World Triathlon events who are not on the programme must arrange screening and doctor sign-off independently.
For athletes within the British Triathlon pathway, a cardiac screening service and doctor sign-off is arranged once a year through the organisation’s performance assessment weekend.
What are the costs of screenings?
Under 35s
Visit testmyheart.org.uk to book a free screening. Elite-level athletes may also be able to access low-cost screenings through a specialist university department.
Over 35s
Take a look at screenmyheart.co.uk, who charge screening from £150 (basic) and £355 (advanced) for ages 16 and over, with results the same afternoon. Private hospital charges vary, but are likely to be at least double. If you have private health care, check to see whether your policy will cover it.
How is the athletic heart different?
Professor Sanjay Sharma, has been the medical director of the London Marathon for 19 years, is the medical doctor for Ride London and also oversaw the medical provision for the ITU World Championship held in London in 2013.
“When people exercise vigorously more than four hours a week, they develop a constellation of structural changes in the heart,” Dr Sharma explains. “Fifty percent of male triathletes and 20% of women’s triathletes’ hearts are considered enlarged.”
This isn’t negative by definition. “They pump well, and contraction and relaxation is good, but the heart can look very lazy when you scan it so the worry is whether there’s something wrong.
“This is the diagnostic conundrum and we have certain measurements we use, such as looking at the thickness of the left ventricle. It’s not uncommon to see 12-14mm, but anything more is not normal – and could indicate a heart muscle fault, or even use of anabolic steroids.”
Professor Sharma thinks men suffer more cardiac incidents than women because their bigger muscle bulk presents more opportunity to stress the cardiac system beyond what it can handle.
“It’s a generalisation, but males are typically bigger than females, and may also be less likely to listen to their bodies. Men have higher levels of circulating testosterone and also cardiovascular systems that age about 10 years before women.”
Why do we see more ‘heart attacks’ in the swim?
Although still uncommon, Dr Sharma says research shows around seven in every 10 deaths in triathlon occur in the swim, and 50-60% show that it was due to an underlying heart problem. Around a third are also first-time participants.
“When diving into cold water, both our vagal system (rest and digest) and sympathetic nervous system (fight or flight) fire, and the imbalance between the two may put the heart into a bad rhythm, especially if you’re predisposed,” he suggests.
“The list of possible causes includes this autonomic conflict, plus underlying cardiac conditions, narrowing arteries, Long QT syndrome [an electrical fault that could be genetic] or even being knocked out through contact.”
While taking personal responsibility is imperative, it’s also incumbent on facilities and race organisers to put safety measures in place.
Sharma adds: “It’s important to place an emphasis on how site facilities such as having a defibrillator nearby and a good medical set-up increase favourable outcomes five-fold.”
5 ways to protect your heart
- Check your risk factors such as high blood pressure or cholesterol. Take advantage of a free NHS check-up if available.
- Look for warning symptoms such as dizziness on exertion or unusually elevated heart rate.
- Don’t exercise if you have a high temperature or virus infection.
- Be wary of supplements such as steroids that might have a negative impact on your heart.
- Consider a heart screen. If you’re under-35 you can book in for free with CRY.
Case study – Kat Matthews
Kat Matthews, 34, is a professional long-course triathlete who finished runner-up in the 2021 Ironman World Championship in Utah and currently holds the Kona run leg record. She trains more than 20 hours a week and here shares her heart screening experience at Leeds Beckett University in 2022.…
How long was the process and what did it cost? “It took 30mins and cost £126.”
What happened? “It was a simple Q&A about personal and family medical history and a discussion to ensure the information I provided was accurate. Then a few mobility-related physical tests and an ECG.”
What were the results? “Nothing of concern from the questionnaire nor the physical examination, with blood pressure, heart rate and rhythm all normal. Typically athletic changes seen to the heart, such as bradycardia (low heart rate) with no contraindications to exercise. Plus a note to arrange a retest in two years.”
Do you have any concerns over heart health as a professional triathlete? “Honestly, no. Until advised to adjust my lifestyle by research professionals it won’t cross my mind. In my opinion and presently on evidence, the endurance lifestyle has to be at the top end of health.”
“But racing as professionals we are accessing a higher proportion of our physical capacity than amateurs and is a considered decision, shown in most professional race calendars. In this respect, I take a lot of confidence from a negative cardiac screening, something I ignored in my 20s.”
Case study – Simon Olney
Simon Olney, 34, is a triathlon coach in the Cotswolds. Six years ago he was living in south London when he had a heart scare.
“Following a tough turbo session I experienced an unusual tightness in my chest and made a precautionary trip to A&E. I expected a once-over and to be sent on my way, but they found elevated levels of troponin in my system, a protein associated with cardiac damage, as the body attempts to repair damaged cardiac muscle.
“They believed I’d had a minor heart attack. It was one of the scariest moments of my life, and my first thought was whether I could still compete in triathlon.
“They did a follow-up blood test, which came back clear late that evening. They believed the high level of ‘trops’ in my blood was due to the muscle damage to my legs from the turbo session. As a precaution I underwent a series of tests including an echogram (ultrasound), more bloods, and a treadmill test to exhaustion while rigged up.
“The cardiologist told me there was nothing wrong with my heart and sent me on my way. The sense of relief was enormous, but it was the day I stopped taking my health for granted.”
Case study – Jonah Marks
Jonah Marks, 17, is a promising London Region Academy athlete who has competed in the British Super Series. A recipient of funding from the Dave Aitchison SportsAid Fund –Aitchison was a 29-year-old triathlete who died suddenly of an undetected heart complaint – Jonah already knew the importance of CRY testing.
“I became aware of the potential dangers of hidden heart problems in athletes when I was lucky enough to be given an award from the Dave Aitchison SportsAid Fund.
“When British Triathlon made CRY testing available to all Super Series athletes [it’s compulsory if they want to go on to compete at elite level], it seemed like a no-brainer. The test was completely painless and now I can carry on training and racing hard knowing that everything’s okay with my heart.”
If any of the contents of this article raises concerns with you, we advise you to reach out to your local GP or doctor, or alternatively call 111 for professional advice.
Next, we take a deep dive into how endurance sport and triathlon affects your musculoskeletal system.
Tim Heming
Freelance triathlon journalist 
