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Irregular heart rhythm was 4.5 times more likely in people with heart scarring. Getty Images<\/p>\nExercise is a wonder drug in so many ways \u2013 we write frequently about the cavalcade of benefits.<\/p>\n
Yet, done to a high intensity, over many years, it is known to stress the body in certain negative ways \u2013 and the heart often bears the brunt.<\/p>\n
A recent study from the University of Leeds, funded by leading UK heart research charity British Heart Foundation, added to this grim news: it found that older male athletes may be at higher risk of dangerous, life-threatening heart rhythms.<\/p>\n
Published in the journal Circulation: Cardiovascular Imaging, the study found that, as people who have spent decades training, they were more likely to have heart scarring than non-athletes. To boot, athletes with scarring were 4.5 times more likely to experience an abnormal heart rhythm episode compared to those without scarring.<\/p>\n
They studied 106 healthy male endurance athletes over the age of 50, none of whom had cardiac symptoms or a diagnosis of cardiovascular disease.<\/p>\n
All were either cyclists or triathletes and had been exercising for 10 or more hours a week for at least 15 years, competing at all levels.<\/p>\n
At the beginning, their hearts were scanned for scarring with MRI and they were fitted with an implantable loop recorder to measure their heart\u2019s rhythm.<\/p>\n
47% had heart scarring, most commonly at the bottom of their left ventricle, the heart\u2019s main pumping chamber. This was over four times higher than a similar demographic group of non-athletes (11%).<\/p>\n
During the two-year study period, 22% of the athletes had at least one episode of ventricular tachycardia (VT), a dangerous form of arrhythmia (irregular heartbeat), which can be deadly when it\u2019s sustained beyond a few seconds. 78% of the 22% had previous heart scarring. Three of the participants had one or more episodes of sustained VT.<\/p>\n
Irregular heart rhythm was 4.5 times more likely in people with heart scarring. Getty Images<\/p>\n
Dr Sonya Babu-Narayan, cinical director at the British Heart Foundation and consultant cardiologist, said:\u00a0\u201cThere\u2019s no doubt that exercise is good for our hearts. It helps to reduce blood pressure and cholesterol, manage our weight, and it boosts our mental health.<\/p>\n
“But in some veteran male athletes, this early research suggests that intense exercise over many years may have affected their heart health.\u00a0\u00a0<\/p>\n
\u201cMore research in veteran endurance athletes \u2013 both in men and women \u2013 will be needed to identify the small number of people who have the kind of heart scarring, together with other risk factors, that mean their life could be saved by having an implantable defibrillator.\u201d\u00a0<\/p>\n
Too many, Cookson
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Brian Cookson threw himself back into racing after leaving the UCI. Mallorca Bike Fotos<\/p>\n
One of the 106 participants in the trial was 74-year-old Brian Cookson, a Brit who led the UCI as president from 2013-2017.<\/p>\n
Following his departure from cycling’s world governing body, he began to train and compete again in bike racing, but in May 2024, while training at the Manchester velodrome, he began to feel unwell.<\/p>\n
A new record heart rate \u2013 238bpm \u2013 signalled all was not well and it took 15 minutes for it to return to normal, which was another red flag. <\/p>\n
He was already aboard the Leeds study, with an implantable recorder fitted, so he got in touch and they were able to see what had happened.<\/p>\n
\u201cThe next day, I got a call. They said, \u2018Stop riding your bike, don\u2019t do anything more strenuous than walking until we can get you in here because we think you need an ICD [implantable cardioverter defibrillator].\u2019\u201d\u00a0<\/p>\n
Cookson had had an episode of VT \u2013 the ventricles were contracting too quickly and weren\u2019t able to pump blood around the body effectively. Untreated, it can cause a cardiac arrest.<\/p>\n
By the end of the summer, he\u2019d been fitted with the ICD, which shocks the heart if it goes into an abnormal rhythm.<\/p>\n
Cookson is cycling again, but is no longer pushing himself like he was. \u201cI keep a closer eye on my heart rate now and if I\u2019m getting to 150bpm I\u2019ll start backing off,\u201d he says.<\/p>\n