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More about Fitness Age
Fitness Age is an indication of how well your body functions physically, relative to how well it
should work, based on things like your gender, age and weight.
The more effective activity you do, the better your Fitness Age becomes.
VO2max is used to calculate your Fitness Age, and is the standard method used to determine a
person's physical fitness. It is the maximum rate of oxygen that your body can use during exercise
per second, per body weight unit. Becoming fitter means your body can use more oxygen, so
your VO2max increases as your fitness level increases.
To help you understand your current fitness level, we calculate your VO2max from your personal
profile and an analysis we do on your heart rate while you are doing a running activity, or estimate
it based on 24/7 tracking if you never do an activity. In laboratory conditions, VO2max is normally
determined through an intense treadmill or home trainer test with a mask that really measures the
oxygen flow into your body. It ranges from about 15 ml/kg/min to 100 ml/kg/min, with higher
being better, and it's different for men and women. Tables 1 and 2 below include shows the
spread and classifications for VO2 max. estimates by age and gender, as provided by The Cooper
Institute.
From your measured VO
2
max, fitness age is calculated by comparing to population averages of
VO
2
max by age and gender that can be found in the American College of Sports Medicine’s
Guidelines for Exercise Testing and Prescription (Ninth Edition). The VO
2
max-to-fitness-age
calculation is different for men and women, because men have on average a higher VO
2
max than
women in all age ranges. For example, if you are a 33 year old woman and your Fitness Age is 27,
your fitness level is the same as the average 27 year old woman in this American College of
Sports Medicine’s study. In other words, because your VO
2
max naturally deteriorates with age,
you are doing great.
We calculate your Fitness Age from your VO
2
max and other factors so you can see how you
perform against others in your age and gender group. The lowest Fitness Age we show is 20
years.
