High‑intensity risk for older athletes
New analysis suggests that years of sustained high‑intensity training can raise cardiovascular risk for athletes aged 35 and older — a finding that has prompted updated European and American cardiology guidance. In plain terms, endurance athletes who keep very high volumes and intensities for decades may need to rethink training balance rather than assuming 'more' is always better. (nltimes.nl)
A runner can log 10-hour training weeks for 20 years, post perfect race splits at 42, and still show heart changes a couch potato never gets. That is the surprise behind new cardiology guidance for so-called masters athletes, the group defined as age 35 and older. (nltimes.nl) Exercise still lowers the risk of heart disease and early death for most people. The concern starts at the far end of the curve, where training stays both very hard and very frequent for years rather than months. (radboudumc.nl) A healthy heart adapts to training the way a biceps adapts to lifting. The chambers can enlarge, the walls can thicken, and the resting pulse can drop because each beat pushes more blood. (vchri.ca) Most of those changes are normal in trained people. Sports cardiologists have spent years learning which changes look like harmless remodeling from training and which ones look more like early disease. (escardio.org) The trouble is that age changes the equation. In athletes older than 35, the leading cause of sudden cardiac death is no longer usually an inherited defect present from youth, but coronary artery disease that builds up over time. (academic.oup.com) Coronary artery disease means plaque inside the arteries that feed the heart muscle. You can picture it like mineral buildup narrowing a water pipe, except the pipe is carrying oxygen to tissue that is working harder during a sprint or a long climb. (academic.oup.com) Another issue is atrial fibrillation, a rhythm problem in the heart’s upper chambers. Instead of beating in a steady pattern, the electrical signal can wobble and fire chaotically, which can feel like fluttering, missed beats, or sudden drops in performance. (heart.org) Researchers are also tracking myocardial fibrosis, which means small areas of scar in the heart muscle. Scar tissue is like a patch in a phone charging cable: the current may still pass, but the weak spot can change how the system behaves under strain. (heart.bmj.com) That brings us to the new paper published in the European Heart Journal on April 6, 2026. It says masters athletes may show higher rates of atrial arrhythmias, coronary atherosclerosis, aortic dilatation, myocardial fibrosis, and exercise-related rhythm disorders than less active peers. (academic.oup.com) The paper is not saying training is bad. It is saying a 50-year-old cyclist doing repeated high-volume, high-intensity blocks for decades should not assume that elite fitness cancels out every cardiovascular risk. (radboudumc.nl) That shift has already reached the guideline level. The European Society of Cardiology and the American College of Cardiology jointly issued this new clinical consensus, and American guidance released in 2025 also added a specific section on masters athletes. (academic.oup.com) (acc.org) The new advice is more targeted than “stop exercising.” Routine screening with coronary calcium scans is still not recommended for low-risk masters athletes, but athletes with intermediate or high risk may need tighter assessment based on symptoms, family history, blood pressure, cholesterol, and training history. (sciencedirect.com) Doctors are being told to look harder at warning signs that endurance athletes often wave away. Chest pressure during intervals, unexplained breathlessness, a sudden drop in pace, palpitations, fainting, or a strong family history of early heart disease now deserve more than a shrug and another training block. (vchri.ca) (academic.oup.com) The hardest message for serious athletes may be the simplest one: more is not always better forever. For a 25-year-old training for a personal best, piling on volume can build fitness, but for a 45-year-old with decades of hard endurance work behind them, the smarter move may be balancing intensity, recovery, and risk checks instead of treating every season like a contest against aging. (nltimes.nl) (acc.org)
