We studied the relationship between taking part in a long-distance ski race and incidence of cardiovascular diseases (CVDs) to address the hypothesis that lifestyle lowers the incidence. A cohort of 399630 subjects in Sweden, half were skiers in the world's largest ski race, and half were non-skiers. Non-skiers were frequency matched for sex, age, and year of race. Individuals with severe diseases were excluded. The endpoints were death, myocardial infarction, or stroke. The subjects were followed up for a maximum of 21.8 years and median of 9.8 years. We identified 9399 death, myocardial infarction, or stroke events among non-skiers and 4784 among the Vasaloppet skiers. The adjusted hazard ratios (HRs) comparing skiers and non-skiers were 0.52 [95% confidence interval (CI) 0.49-0.54] for all-cause mortality, 0.56 (95% CI 0.52-0.60) for myocardial infarction and 0.63 (95% CI 0.58-0.67) for stroke and for all three outcomes 0.56 (95% CI 0.54-0.58). The results were consistent across subgroups: age, sex, family status, education, and race year. For skiers, a doubling of race time was associated with a higher age-adjusted risk of 19%, and male skiers had a doubled risk than female skiers, with a HR 2.06 (95% CI 1.89-2.41). The outcome analyses revealed no differences in risk of atrial fibrillation between skiers and non-skiers. This large cohort study provides additional support for the hypothesis that individuals with high level of physical activity representing a healthy lifestyle, as evident by their participation in a long-distance ski race, have a lower risk of CVD or death.