Exercise is medicine: evidence repeats itself

Physical activity is well-known to be an important factor in the prevention of almost all chronic diseases. The beneficial effects of physical activity are seemingly endless. Regular physical activity improves, for example, blood pressure and glucose control, lowers the risk of depression, improves cardiovascular outcomes, and stimulates our immune system to shield us from severe infections such as COVID-19 (1,2). The PURE study already demonstrated that higher levels of physical activity were associated with a lower risk of cardiovascular disease and death (3). Therefore, sufficient physical activity (>150 minutes of moderate physical activity per week) is recommended by the World Health Organisation.

The study by Steenkamp et al. in the British Journal of Sports Medicine was a retrospective observational study in South Africa of more than 65000 patients (4). In contrast to earlier studies in COVID-19, physical activity was objectively measured by smart devices, clocked gym attendance, or recorded participation in mass sports events as part of a global health promotion and behavioural change programme (4). Steenkamp et al. demonstrated that physical activity, like in many other chronic diseases, had protective effects in patients with COVID-19. These results are comparable with earlier studies where physical activity was based on self-reported physical activity (5).

Higher levels of physical activity were associated with significantly lower rates of hospitalisation, intensive care unit admission, ventilation, and mortality. Surprisingly, these effects were already seen at moderate levels of physical activity, which was defined as 60 to 149 minutes per week (4). This indicates that even physical activity levels lower than the guidelines recommend have preventive effects when contracting COVID-19.

Importantly, the benefit from physical activity may be even more significant in older people or people with cardiovascular risk factors (4). This emphasises once again the importance of physical activity in both primary and secondary prevention.

In summary, this study again highlights the beneficial effects of physical activity. The study, based on objectively measured data, demonstrates that physical activity reduces the risk of COVID-19 related hospitalisation, intensive care unit admission, and mortality. Moreover, the preventive effects even occur at suboptimal (60-149 minutes per week) physical activity levels. Even more focus is needed on initiatives to increase daily physical activity levels at all ages.