Cardiorespiratory fitness, body composition, and all-cause and cardiovascular disease mortality in men

Background: Cardiorespiratory fitness and body fatness are both related to health, but their interrelation to ah-cause and cardiovascular disease (CVD ) mortality is unknown. Objective: We examined the health benefits of leanness and the hazards of o besity while simultaneously considering cardiorespiratory fitness. Design: This was an observational cohort study. We followed 21925 men, aged 30-83 y, who had a body-composition assessment and a maximal treadmill exe rcise test. There were 428 deaths (144 from CVD, 143 from cancer, and 141 f rom other causes) in an average of 8 y of follow-up (176742 man-years). Results: After adjustment for age, examination year, cigarette smoking, alc ohol intake, and parental history of ischemic heart disease, unfit (low car diorespiratory fitness as determined by maximal exercise testing), lean men had double the risk of all-cause mortality of fit, lean men (relative risk : 2.07; 95% CI: 1.16, 3.69; P = 0.01). Unfit, lean men also had a higher ri sk of all-cause and CVD mortality than did men who were fit and obese. We o bserved similar results for fat and fat-free mass in relation to mortality. Unfit men had a higher risk of all-cause and CVD mortality than did ht men in all fat and fat-free mass categories. Similarly, unfit men with low wai st girths (<87 cm) had greater risk of all-cause mortality than did fit men with high waist girths (greater than or equal to 99 cm). Conclusions: The health benefits of leanness are limited to fit men, and be ing fit may reduce the hazards of obesity.