Cardiorespiratory fitness (CRF) has been shown to be an independent predictor of all-cause and cardiovascular mortality, as well as health outcomes such as cardiovascular disease, hypertension, diabetes mellitus, and metabolic syndrome. During the last four decades, national guidelines for physical activity and fitness have emerged in an ongoing effort to improve health outcomes through enhanced CRF risk profiles.
Purpose: The purpose of the study was to describe the secular trend in CRF as a function of decade and age in a large cohort of men during the past 40 yr.
Methods: A cross-sectional analysis of baseline fitness data collected during comprehensive medical examinations of 52,785 men age 20-74 yr evaluated at the Cooper Clinic in Dallas, TX, from 1970 to 2009 who completed a maximum treadmill exercise test for estimation of aerobic capacity was conducted. Comparisons were made between mean fitness levels in each decade stratified by five age groups.
Results: Mean CRF in MET from estimated V·O 2max has increased overall approximately 1 MET during a 40-yr period for each of the five age groups (P < 0.0001). The greatest change occurred during the 1970s to 1980s with minimal subsequent increase and a small decline commencing in the last decade especially in younger men.
Conclusions: In a large cohort of men, average CRF has improved during the last 40 yr with a slight decline in the favorable trend notable in the most recent decade.