Objective: To identify the most common causes of death during sports activity in the population of Hamburg, Germany, and to identify which groups of sportspeople are particularly in danger of dying during sports and in which types of sport most fatalities occur.

Design and setting: We performed a 10-year autopsy-based retrospective study of all 48 335 fatalities in Hamburg and the surrounding areas that were subjected to police investigations between 1997 and 2006 and screened for sports-related deaths. The main outcome measure was cause of death depending on form of sport, age and risk factors.

Results: Most of the fatalities were male. In natural deaths, cardiac causes were the most frequent causes found, with running and football being the most frequent forms of sport in which death had occurred. In some of the cases, sports medical examinations had been performed before death, certifying eligibility for the respective activity. Traumatic deaths were found in all age groups, with younger age groups more likely to have traumatic than natural deaths, and as expected, occurred more commonly in “risky” outdoor activities.

Conclusions: Although exercise can have beneficial effects on health, fatalities related to sports activity occur. Cardiac disease is the main cause of sudden death from natural causes. In patients with pre-existing coronary heart disease, left ventricular hypertrophy constitutes a risk factor for exercise-related sudden death. Traumatic deaths often happen on holiday outside the person’s country of dwelling, and are most commonly attributable to drowning and blunt trauma. Preparticipation medical screening cannot always prevent fatal incidents during sports activity. Postmortem macroscopic and histological examination can clarify the cause of death and legal issues.