Research tells us that the performance decline we typically experience with aging has a lot to do with how active we are while growing older. For example, a paper released in 2000 examined the combined effects of age and activity level over time. The researchers reviewed 242 studies comparing aging and VO2 max involving 13,828 male subjects. Each of the subjects was assigned to one of three groups based on how active they were: sedentary, moderately active exerciser, or endurance-trained runner. Aerobic capacity was highest in the runners and lowest in the sedentary group. No surprises there. The aerobic capacity changes per decade of life were sedentary, 8.7 percent; active, 7.3 percent; runners, 6.8 percent. What this means is if, at age 30, a man had a VO2 max of 60 and then for the next 30 years didn’t exercise and lived a “normal” (sedentary) life, he could expect his aerobic capacity at age 60 to be around 46. If he was moderately active, it would be about 48. And if he trained as an endurance runner, it would be in the neighborhood of 49. Those are not significant numeric changes. But for normal folks who generally see VO2 max declines of 10 percent and greater for a 10-year period, these numbers are really high.
But regardless of the actual size of the change, here’s the main message: The study further reported that the subjects who were endurance-trained runners significantly decreased their volume (miles run per week) and training intensity as they got older. That’s a common practice with aging athletes. So maybe it’s not simply working out that maintains aerobic capacity and therefore, in part, race performances; instead, it is how much training you do and how intensely you do it.
Yes, I realize that I am repeating the same message from earlier chapters in “Fast After 50.” It’s a critical lesson for getting faster regardless of your age.