Cardiorespiratory fitness, lifestyle factors and cancer risk and mortality in Finnish men

Background: Physical fitness along with lifestyle factors may have important roles in the prevention of cancer. We examined the relationship between common lifestyle factors such as energy expenditure, physical activity and maximal oxygen uptake (VO_2max), nutrition and smoking habits and the risk of cancer. Methods: A population-based cohort study was carried out in 2268 men from Eastern Finland with no history of cancer. They were followed up for an average of 16.7 years. The outcome measures were cancer incidence (n = 387) and cancer mortality (n = 159). Results: Men with VO_2max of more than 33.2 mL/kg/min (highest tertile) had 27% (95% confidence interval (CI) 0.56-0.97) decreased cancer incidence and 37% (95% CI 0.40-0.97) reduced cancer mortality than men with VO_2max of less than 26.9 mL/kg/min (lowest tertile) after adjustment for age, examination year, alcohol, smoking, socioeconomic status, waist-to-hip ratio and energy, fibre and fat intake. The risk reduction was mainly due to decreased risk of lung cancer in fit men. The adjusted risk of cancer was 0.73 (95% CI 0.55-0.98) among fit (VO_2max ≥ 26.9 mL/kg/min) men with the total energy expenditure of physical activity over 2500 kcal/week. A total of 290 active (energy expenditure >2500 kcal and at least 2 h of physical activity per week) men with a favourable lifestyle (good fitness, balanced diet and non-smoking) had an adjusted relative risk of 0.63 (95% CI 0.46-0.87) for cancer. Conclusion: Favourable lifestyle including good cardiorespiratory fitness and healthy dietary habits with active and non-smoking lifestyle considerably reduces the risk of cancer.