Keeping fit could help you avoid heart rhythm disorder and stroke, new research suggests. The study of more than 15,000 people found that physical fitness is linked with a lower likelihood of developing both conditions. Atrial fibrillation – irregular and often fast heartbeat – is the most common heart rhythm disorder, affecting more than 40 million people worldwide. The findings indicate that keeping fit may help prevent atrial fibrillation and stroke Dr Shih-Hsien Sung Patients with the condition have a five-fold higher risk of stroke than their peers, experts suggest. Study author Dr Shih-Hsien Sung of the National Yang Ming Chiao Tung University, Taipei, Taiwan said: “This was a large study with an objective measurement of fitness and more than 11 years of follow up. “The findings indicate that keeping fit may help prevent atrial fibrillation and stroke.” The study examined whether fitness was related to the likelihood of developing atrial fibrillation. It included 15,450 people without atrial fibrillation who were referred for a treadmill test between 2003 and 2012. Fitness was assessed using a protocol where people are asked to walk faster and at a steeper grade in successive three-minute stages. Their fitness was calculated according to the rate of energy expended, which was expressed in metabolic equivalents (METs). Follow-ups looked at whether people developed atrial fibrillation, stroke, heart attacks, or whether they had died. During an average follow-up period of 137 months, 515 participants (3.3%) developed atrial fibrillation. Each one MET increase on the treadmill test was associated with an 8% lower risk of atrial fibrillation, 12% lower risk of stroke and 14% lower risk of major adverse cardiovascular events (MACE – a composite of stroke, myocardial infarction and death). People in the study were divided into three fitness levels according to METs achieved during the treadmill test. The levels were low (less than 8.57 METs), medium (8.57 to 10.72) and high (more than 10.72). According to the findings presented at the ESC Congress 2023 in Amsterdam, the probability of remaining free from atrial fibrillation over a five-year period was 97.1%, 98.4% and 98.4% in the low, medium and high fitness groups, respectively. Read More Charity boss speaks out over ‘traumatic’ encounter with royal aide Ukraine war’s heaviest fight rages in east - follow live How to give your home a proper summer sort out What you really need to do in autumn to keep your lawn in shape MRI screening for prostate cancer could help save lives, study finds