Purpose:
Running is becoming an increasingly more popular form of leisure activity. However, intense physical activity, such as running a marathon, can put a significant strain on the body and lead to the use of painkillers to reduce or avoid pain. Therefore, the purpose of the research was to determine the percentage of participants in the Poznań Marathon taking analgesics before or during the run and to investigate the runners’ knowledge about the possible negative health effects of such behaviour.

Methods:
The study was carried out in 3 consecutive years (2014–2016) among 308 runners participating in the Poznań Marathon. The respondents completed a survey consisting of 3 parts: (1) personal details, (2) use of analgesics before and/or during the marathon run, and (3) the runner’s awareness of the possible negative effects of using such medicines during increased physical activity.

Results:
Taking analgesics before or during a marathon run was declared by 18.6%, 14.9%, and 16.8% of the participants in years 2014, 2015, and 2016, respectively. Compared with men, women used painkillers more frequently (22.3% vs. 16.1%). On average, 59.3% of runners believed that using analgesics might be harmful to their health and increase the risk of injury, but 39.8% of them took painkillers anyway.

Conclusions:
Nearly every sixth participant of the Poznań Marathon used analgesics before or during running because of the pain they experienced or expected. The awareness of analgesic-related side effects did not stop the runners from using painkillers.