New research from the University of Leeds flags a specific heart risk for male endurance athletes over 50: years of high-intensity training can coincide with dangerous rhythm disturbances when scarring is present. The study tracked healthy runners and cyclists with wearable trackers and implantable monitors, finding a notable link between myocardial scarring and episodes of ventricular tachycardia during or after exercise. While exercise still delivers major health benefits, this work suggests targeted screening for older male athletes with long training histories could catch hidden problems early. Practical steps like talking to a cardiologist, watching for warning symptoms, and using monitoring tools can make all the difference.
The study followed 106 male runners and cyclists, all described as healthy, using a combination of wearable activity trackers and implantable heart monitors. That mix of continuous monitoring and real-life training data gave researchers unusually clear insight into how the heart behaves during intense endurance work. Importantly, the population here is specific: older male endurance athletes with a long history of high-volume training, not casual exercisers or mixed-age cohorts.
The results were striking: about one in four athletes experienced episodes of ventricular tachycardia, a fast and potentially life-threatening heart rhythm if it continues. Among those who had episodes, roughly three in four showed evidence of myocardial scarring on imaging. Myocardial scarring can create electrical instability in the heart, which helps explain why an otherwise well-trained athlete might suddenly experience dangerous rhythms.
“Our study shows that exercise was only associated with a risk of developing abnormal heart rhythms in those who were already high risk due to heart scarring,” lead author Wasim Javed said. That distinction matters: the research does not paint exercise as the root cause, but rather as a potential trigger in the presence of existing damage. It reframes the question from “Is exercise bad?” to “Who needs extra cardiac attention?”
“Athletes who developed abnormal heart rhythms were not exercising more or harder than athletes without abnormal heart rhythms,” Javed said. In other words, training load alone did not explain which athletes experienced problems. This points toward underlying structural or electrical issues in the heart as the real differentiator, not pure mileage or intensity.
“This suggests that exercise itself is not the cause but could act as a trigger for dangerous heart rhythms in those athletes already with an underlying heart issue.” That brings a practical takeaway: screening and detection. Older male athletes, especially those with decades of competition or training, should consider cardiac evaluation beyond the basic checkup. Tests can include ECG, echocardiography, cardiac MRI to look for scarring, Holter monitoring, or even implantable loop recorders when unexplained symptoms occur.
Major health groups emphasize the benefits of activity: regular exercise lowers risk for cardiovascular disease and stroke, strengthens the heart, and improves circulation. Cardiologists note that the vast majority of people reap net positive effects from being active, so this research should not scare recreational athletes away from movement. Instead, it encourages targeted vigilance where risk seems to cluster.
Symptoms deserve attention: unexplained dizziness, palpitations, fainting, breathlessness on effort, or new chest discomfort are signals that should prompt a medical visit. Wearable heart monitors and implantable devices can catch intermittent arrhythmias that a single clinic ECG might miss. For many athletes the fix is simple monitoring and management, not cessation of training.
Practical steps for older endurance athletes include scheduling periodic cardiac screening with a physician familiar with athletes’ hearts, keeping an eye on symptoms, and considering advanced imaging if suggested. Training plans can be adjusted individually, with periods of lower intensity or focused recovery if a clinician recommends it. The goal is to keep the heart strong and the athlete active, while reducing the small but real risk tied to scar-related rhythm problems.
