It is often said that age is just a number. But even if it is just a number, it's a number that's attached to you and which follows you around all your life. It's also a number that implies a lot about you which is not accurate, especially from a health point of view. So if, from a health point of view, age isn't the right number, what would be the right one? It seems that the right number, as far as health is concerned, is what is termed your Fitness Age. And there are two pieces of good news with regard to your fitness age. Firstly, it is not the same as your chronological age, and secondly - and more importantly - it is totally subject to your efforts to lower it, with important consequent benefits.
Fitness age is a term coined by a group of researchers at the Norwegian University of Science and Technology who in 2014 discovered, after analysing data from a study of over 4,600 healthy subjects with ages ranging from 20 to 90, a strong correlation between cardiovascular fitness and overall health. Furthermore they concluded that the most accurate measure of a person's cardiovascular fitness was their VO2 max, which is an expression of the volume of oxygen they can absorb and make use of. The higher their VO2 max, the more oxygen they can absorb and use, so the fitter they are.
Following that discovery, they compiled a table of average values for VO2 max across the various age ranges and then compared the values of individual subjects in each age range against the mean values of other age ranges. What came out of it was the idea of Fitness Age. If for example you are a, presumably, fit and active person aged, say, 65 and your personal VO2 max was the same as the mean value for a lower age, say 45, then your Fitness Age would be 45, twenty years younger than your chronological age. And there were an awful lot of good things that accompanied that difference because your physical capabilities would be more like a 45-year-old than a 65-year-old, not just in sport and exercise, but in life generally.
Healthwise, they found that people who had the lowest VO2 max were five times more likely (for women) and eight times more likely (for men) to have what they described as "a cluster of cardiovascular risk factors" than were those whose VO2 max was in the highest 25%. Not only that, but a subsequent study also showed a strong correlation between cardiorespiratory fitness, i.e. VO2 max, and lifespan.
So evidently, a higher VO2 max is a good thing, and it is not an unshakeable number, unlike your chronological age.
The researchers felt that it would be beneficial for anyone to be able to measure their own Fitness Age, so they created an online Fitness Age test where you can do just that.
One person who took the test was Dr Pamela Peeke, assistant professor of medicine at the University of Maryland. She herself is in her sixties and is also a competitive triathlete. Her fitness age came out at 36. As she is on the board of the organisation that runs the National Senior Games in USA, an athletics competition for over-50's, she decided along with Dr Ulrik Wisloff, the creator of the fitness age calculator, to do a mass test on the athletes participating in the games.
All of the entrants to the Games were offered the test and over 4,200 of them took part. The results showed that there was an average 25 years' difference between the athletes' average chronological age of 68 and their average fitness age of 43! That's some benefit from exercising. And, as Dr Peeke also said, although the athletes in the Senior Games train seriously, many of them didn't start training until later in life. Even so they still managed to improve their cardio fitness, as expressed by their VO2 max, of course, to a level where they lowered their fitness age substantially.
So if age is just a number, which is attached to you and follows you round all your life and is really an irrelevance, then health and fitness is also a number, but a number with relevance, and one which you can have a good deal of influence on, simply by working at your fitness.
So if you're going to worry about a number, worry about the right one - and do something about it.