The speed at which you walk can reveal profound insights into your brain's rate of ageing – with slower walkers having smaller brains and fundamental differences in crucial structures.

It might seem trivial, but how quickly you can walk from A to B can reveal a great deal about the inner workings of your body and mind. Research has shown that the speed at which you walk to the shops, the local park, or the bus stop, can predict your chance of being hospitalised, suffering a heart attack, and even dying. In fact, a person's gait speed can even be used to reveal their rate of cognitive ageing.

The walking speed test is a way of assessing someone's functional capacity – their ability to perform daily tasks around the house and maintain independence. It can also reveal how frail a person is, and predict how well they will respond to rehabilitation after a stroke.

Although it is normal for people to walk more slowly as they age, a precipitous decline in the speed of someone's gait could indicate that something more serious is going on.

"When a person's normal walking pace declines, it is often associated with underlying health declines," says Christina Dieli-Conwright, a professor of medicine at Harvard Medical School, who studies the effects of exercise on cancer prognosis.

"It might be that the person has a chronic condition which has meant that they haven't been moving as much or have become sedentary. That means that, more than likely, they've experienced a decrease in muscle strength, and joint mobility, which unfortunately leads to further health declines," says Dieli-Conwright.

To perform the walking speed test, all you need is a stopwatch and a way of measuring distance, such as a tape measure. There are two common versions.

If you are outside and you have lots of space, you could try the 10m (33ft) walking speed test. First, measure out 5m (16.5ft), followed by another 10m. To get started, it's recommended to walk for 5m to get up to your normal speed, then walk at your normal pace for 10m. To calculate your walking speed simply divide 10m by the number of seconds it took to walk that distance.

If you're at home and space is more limited, you could try the 4m (13.2ft) walking speed test. With this test, measure out 1m (3.3ft), followed by 4m. The idea is to use the first metre to get up to speed, then time how long it takes to walk for 4m at your usual pace. To work out your speed, divide four metres by the number of seconds it took you to walk that distance.

Find out how you compare

For an idea of how you compare to other people, the average walking speed of a 40-49 woman is 1.39m/s (4.6ft/s), and 1.43m/s (4.7ft/s) for a 40-49-year-old man.

If you are aged 50-59, then the average walking speed is 1.31m/s (4.3ft/s) for a woman, and 1.43m/s (4.7ft/s) for a man.

For 60-69 year-olds, average gait speed falls to 1.24m/s (4.1ft/s) for a woman, and 1.43m/s (4.7ft/s).

For 70-79 year-olds, average walking speed is 1.13m/s (3.7ft/s) for a woman, and 1.26m/s (4.16ft/s) for a man.

Finally, for 80-89 year-olds, gait speed is around 0.94m/s (3.1ft) for a woman, and 0.97m/s (3.2ft/s) for a man.

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