What's your fitness age?

What is fitness age?

We know that fitness has a very strong connection to wellness and lifespan. Fitness age provides an actual measurement of these life extending benefits. 

Unlike chronological age, fitness age can rise and fall according to your training regime and aerobic capacity. 

Suitable and consistent training can lead to a reduction, or improvement in your fitness age, and this may correlate with a longer life expectancy. 

On the contrary, an inactive lifestyle may accelerate ageing, would translate to an older fitness age.

What does fitness age actually measure?

During exercise, a number of physiological changes occur, including an elevation of your heart rate, breathing rate and oxygen uptake. 

As you exercise, it will progressively become harder as the duration and/ or intensity increases. There will become a point where, no matter how hard you try, your body can no longer utilise any more oxygen (which it needs to function). 

This point is referred to as your VO₂ max, or maximal oxygen uptake, and is the maximal volume of oxygen that can be inhaled and absorbed by the body. This is the primary measure of fitness age. 

Oxygen is used to break down carbohydrates, fats and protein into fuel that helps your muscles function. VO₂ max is therefore a specific measure of your body’s ability to take in, absorb and use oxygen. It is considered to be a reliable indicator of cardiovascular (aerobic) fitness, and possibly your potential as an endurance athlete. 

How do you measure VO2 max?

VO2 max is measured in millilitres of oxygen per kilogram of body weight per minute. To accurately measure this, you need a gas chamber, or a connection to a gas analyser - which is not practical!

Fortunately, there are a number of tests and online calculators that can predict your fitness age, and your VO2max, like this one developed by researchers at the Norwegian University of Science and Technology.

While there is no gold standard measure of fitness age, seek out a calculator that asks about your age, how frequently you exercise and your weight and height, or preferably, your waistline measurements. It’s also wise to bookmark the calculator you use, as it’s important to re-enter your data on the same calculator in the future to measure any changes reliably.

How old are you really?

While your VO2max is influenced by your chronological age, it’s also strongly influenced by your training regimen and lifestyle. In general terms, the fitter you are, the more oxygen your body can utilise. Use the following steps to calculate an estimate of your fitness age.

• Step 1 – AGE - Enter your chronological age into a calculator
• Step 2 – EXERCISE FREQUENCY - Subtract the number of days each week that you exercise for at least 30 minutes at a low to moderate intensity (where your heart rate is elevated)
• Step 3 – EXERCISE INTENSITY - Subtract the number of days each week you engage in interval training where you exercise at a very high intensity for at least 10 minutes
• Step 4 – BODY FAT - For women, add “3” if your waistline measurement at the widest point is above 90cm. For men, add “3” if your waistline measurement at the widest point is above 100cm
• Step 5 – SMOKING STATUS - Add “0” if you don’t smoke. Add “3” if you are a light smoker (less than 8 cigarettes a week), and add “6” if you smoke more 9 or more cigarettes a week
• Step 6 – SITTING - Add “2” if you have a desk bound job, or if you sit for over 9 hours a day at least five days a week
• Results – After completing steps 1 to 6, you should have a number that represents your fitness age. Ideally, your fitness age is younger than your chronological age. If it’s not, review the questions in steps 1 to 6, and look for ways you can make positive changes to reduce your fitness age