A Comparison of Longitudinal Changes in Aerobic Fitness in Older Endurance Athletes and Sedentary Men.

OBJECTIVES: To compare the longitudinal changes in maximal aerobic capacity (VO2 max) in healthy middle aged and older athletes and sedentary men. DESIGN: A cohort study with mean follow-up of 8.7 years (range 4.0–12.8). SETTING: Outpatient research at a tertiary hospital. PARTICIPANTS: Forty-two healthy, middle aged, and older athletes (initial age 64 ± 1 year) and 47 healthy sedentary men of comparable age recruited for research studies. MEASUREMENTS: VO2 max during a maximal treadmill test. RESULTS: At baseline, the cross-sectional rates of decline in VO2 max with age (slope) were virtually identical in the athletes and sedentary men (-0.42 versus -0.43 mL·kg-1 · min-1 ·year-1 ). At follow-up, the VO2 max had declined by 11.9 ± 1.1 mL·kg-1 ·min-1 (22%) in the athletes, a crude average rate of -1.4 ± 0.14 mL·kg-1 ·min-1 ·year-1 . By comparison, the VO2 max declined by 4.4 ± 0.6 mL·kg-1 · min-1 (14%) in the sedentary men, a crude average rate of change of -0.48 ± 0.07 mL·kg-1 ·min-1 ·year-1 . Therefore, the observed absolute rate of longitudinal decline in VO2 max in the athletes was triple that of the sedentary men (P = .001) and significantly greater than the decline predicted by their baseline cross-sectional data (P = .001). Post hoc analyses of the longitudinal data in the athletes based on the training regimens over the follow-up period demonstrated that the seven individuals who continued to train vigorously (“high training”) had no significant decline in VO2 max (0.28% change in VO2 max per year). By contrast, the VO2 max declined by 2.6% per year in the “moderate training” group (N = 21),... [ABSTRACT FROM AUTHOR]