MUSCULOSKELETAL FITNESS AND ALL-CAUSE MORTALITY

Abstract

Musculoskeletal fitness is related to health status and independent living in the elderly; however, little is known about its relationship with all-cause mortality. The purpose of this study was to quantify the relationship between several indicators of musculoskeletal fitness and all-cause mortality in the Canadian population. The sample consisted of 8,147 people (3,954 males and 4,193 females) between the ages of 20 and 69 who originally participated in the 1981 Canada Fitness Survey. Indicators of musculoskeletal fitness included sit-ups, push-ups, combined hand grip strength, and sit-and-reach trunk flexibility. There were 269 deaths in the 13 years following the Canada Fitness Survey, and 101,685 person-years of follow-up. Proportional hazards regression was used to estimate the risk of mortality across baseline quartiles of musculoskeletal fitness measures. All models included the effects of age, smoking status, body mass, and estimated VO2max as covariates, and the upper quartile was set as the reference group. There was no increased risk of all-cause mortality in the lower quartiles of trunk flexibility or push-ups; however, there was a significantly higher risk in the lower quartile of sit-ups in both males (HR = 2.72, 95% CI 1.56–4.64) and females (HR = 2.26, 95% CI 1.15–4.43). Grip strength was not predictive of mortality in females, although there was a 49% increased risk of death in the lower quartile of grip strength in males (HR = 1.49, 95% CI 0.86–2.59). The results suggest that some components of musculoskeletal fitness, particularly abdominal muscular endurance, are predictive of mortality in the Canadian population.