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BACKGROUND: We studied the association between taking part in a long distance ski race and cancer incidence to address the hypothesis that a lifestyle involving a high degree of physical activity (PA) lowers cancer incidence with a pattern that is different by cancer site.

METHODS: Cancer incidence was estimated in a large cohort of skiers (n=185,412) participating in the Vasaloppet long distance ski race in Sweden 1989-2010 and non-participants in the ski race, randomly selected from the Swedish general population (n=184,617). Data include race finishing times as a measurement of physical fitness. Hazard ratios (HRs) and net probability of cancer over twenty years of follow-up were estimated for all invasive cancer, and separately for prostate, breast, colo-rectal and lung cancer, and groups of cancers with presumed relation to lifestyle.

FINDINGS: Participating in Vasaloppet was associated with a relative risk reduction for all invasive cancer of 6% (95% confidence interval 2-9%) and a relative risk reduction of 32% (95% confidence interval 28-37%) of cancer sites where there is epidemiological evidence that smoking, bodyweight, regular PA and consumption of fruit and vegetables are aetiological factors. For skin cancer the risk was increased, as for prostate cancer. Skiers with shorter finishing times had lower incidence of cancer.

INTERPRETATION: This study indicates that it is unrealistic to reduce overall population cancer incidence drastically with life style. However, cancers that are epidemiologically associated with life style factors were significantly reduced by what presumably is a blend of non-smoking, normal body weight, sound dietary habits and PA. Our data thus provide additional support for present days' recommendations about life style prevention. Higher health awareness is associated with attendance to screening, which may explain our results for prostate cancer.

FUNDING: University fund, independent funds from an insurance company and a private foundation.

AIMS: To study whether a high level of physical activity prior to myocardial infarction (MI) also protects against recurrent MI (re-MI) or death.

METHODS AND RESULTS: A longitudinal study of a primary cohort consisting of 204,038 skiers with a proved substantially high level of physical activity in the world's largest long-distance ski race, Vasaloppet, and 499,543 non-skiers selected from the Swedish population. Individuals with severe diseases at baseline were excluded. In the nationwide clinical register, Swedeheart, we identified 7092 individuals with a first MI incident between 1989 and 2010. Of these, 1039 (0.5%) were skiers and 6053 (1.2%) were non-skiers. One hundred and sixty-three (15.7%) skiers and 1352 (22.3%) non-skiers suffered a re-MI or died during follow-up (median 4.44 years), corresponding to an incidence rate of 38.9 (95% confidence interval (CI) 33.2-45.4)/1000 person-years and 55.6 (95% CI 52.7-58.7)/1000 person-years, respectively. Severity of MI in both groups was the same. For skiers compared to non-skiers the unadjusted hazard ratio (HR) for re-MI was 0.66 (95% CI 0.52-0.82). For death or re-MI, HR was 0.70 (95% CI 0.59-0.82) with consistent results in subgroups based on race year, age, gender, education level, marital status. After adjustment for also smoking, diabetes, hypertension and cardiovascular medication, HR was 0.80 (95% CI 0.67-0.97).

CONCLUSIONS: This large cohort study supports the hypothesis that patients with MI and with prior physical activity and healthy lifestyle, as evidenced by their participation in a long-distance ski race, have a lower risk of subsequent re-MI or death.

Background Physical activity is of benefit for primary prevention of cardiovascular diseases, but it appears to increase the risk for atrial fibrillation. We aimed to study a cohort of patients following a first stroke in individuals with previous high physical activity, compare them to the general population with respect to recurrent stroke and death, and relate these to atrial fibrillation.

Methods and Results From the participants of the Vasaloppet, the world's largest ski‐race, and matched individuals from the general population (n=708 604), we identified 5964 patients hospitalized with a first‐time stroke between 1994 and 2010. Individuals with severe diseases were excluded. One half percent of skiers and 1% of nonskiers were hospitalized due to stroke. The incidence rate was 8.3 per 100 person‐years among skiers and 11.1 among nonskiers. The hazard ratio (HR) for recurrent stroke or death between the 2 groups was 0.76 (95% CI 0.67 to 0.86). The result was consistent in subgroups. The HR for death was 0.66 (95% CI 0.56 to 0.78) and for recurrent stroke 0.82 (95% CI 0.70 to 0.96). After adjustment for smoking and socioeconomic factors, the HR for death was consistent at 0.70 (95% CI 0.56 to 0.87) while the HR for recurrent stroke was not statistically significant. Outcomes for skiers with atrial fibrillation tended to show a lower risk than for nonskiers.

Conclusions This large cohort study supports the hypothesis that patients with a stroke and with prior regular physical activity have a lower risk of death, while their risk for recurrent stroke is similar to that of nonskiers. The skiers had a higher incidence of atrial fibrillation, but still no increased risk of recurring stroke.