A study investigating the belief that too much exercise can be bad for the heart has found that the heart’s structure and function does adapt to high levels of habitual physical activity but these changes stay within normal ranges.
The study, published on 13 August in the European Heart Journal, was carried out by researchers funded by the National Institute for Health and Care Research (NIHR) Leicester Biomedical Research Centre (BRC).
Professor of Physical Activity, Sedentary Behaviour and Health at the University of Leicester, Tom Yates, said: “Some fairly extreme changes have been observed in the hearts of endurance athletes, as the cardiac muscles and chamber sizes adapt to the high levels of work it has to do.
“In a small number of cases, these changes overlap with indicators of heart conditions that we would normally treat, such as cardiomyopathies.
“In this study we wanted to explore how the heart adapts to high levels of habitual physical activity in those who exercise recreationally, as much of the research in this area has been on the hearts of elite or professional athletes.”
Data on 5,977 women (61 years) and 4,134 men (63) from the UK Biobank were analysed in this study.
Levels of average daily moderate-to-vigorous physical activity, vigorous-intensity physical activity, and total physical activity in these participants (which had been assessed by wrist worn accelerometers) were compared to measurements of the structure and function of their heart.
These measures, which had been taken using gold-standard cardiac magnetic resonance methods, included left ventricular end diastolic chamber volume, wall thickness, and ejection fraction.
Levels of moderate-to-vigorous physical activity in this group were as high as 288 minutes per day for women and 240 minutes each day for men.
Professor of Cardiac Imaging at the University of Leicester and co-investigator on the study, Gerry McCann, said: “We saw that in those people with the highest levels of regular physical activity, the heart’s pumping chambers were larger than those who were inactive, however these adaptions remained within normal ranges.
“In addition, there was no evidence that the heart’s muscles thickened to unhealthy levels.
“Therefore, in this population, there was no evidence that high levels of recreational physical activity were associated with heart physiologies that mimic heart disease.”
Professor Tom Yates concluded: “Those who enjoy high levels of recreational exercise should find these results reassuring.”
For the full paper please visit the European Heart Journal website.