Everybody is counting steps on all kinds of devices, but how many do we really need?
The benefits of even moderate regular exercise are so well-established by medical science that it is a wonder it hasn’t been made compulsory. The number of ailments–from diabetes to depression–for which a doctor is likely to tell you “take two running shoes and call me in a year” is astonishing, and growing every day.
This has led to many of us obsessing over step counts on Garmins, Apple Watches, Fitbits and smartphones, which is generally a good thing if it means we get more exercise. The big question is, though, how many steps do we need?
We have probably all heard of the 10,000 step challenge, which seems very official and has its own website and everything. Clearly, the figure is the result of scientific research and consultation with doctors, heart specialists, exercise physiologists, right?
Actually, the 10,000 step figure was a marketing strategy dreamed up by a Japanese manufacturer of pedometers in 1965 (it was a darn good one too). It is not, however, based on science, but science has been done, and it tells us a few important things.
Not all steps are created equal
I sometimes run to work from my home in Kenmore, a distance of around 11 kilometres, and according to my trusty Garmin that takes around 8,500 steps or so. Last Sunday, I did 3.5 hours of housework, and according to the same device clocked up 11,000. I can tell which one was harder though!
The science backs this up, noting that 10,000 normal walking steps is the equivalent of 25 minutes of moderate-to-vigorous exercise, which is not enough. A study of 4840 people in the US found that people who were active for 100 minutes a day had the lowest mortality rates (that is, they lived longer).
So, how many steps?
This depends on how you do the steps. If the only thing you do is stroll about at a normal pace, you will probably need to hit more than 20,000–which is a tough ask. At a brisk walking pace, however, 15,000 will be enough–and the higher the intensity the fewer steps you need.
For example, walking up four flights of stairs gets you into the moderate to vigorous category, as does a brisk walk. Running, taking an exercise class or doing a circuit will up the ante further.
What if I can’t fit that in with my life?
Don’t despair! For people who currently don’t do much at all, even 30 minutes of any activity that lifts your heart rate would halve the mortality rate in this group. Also, the benefits of exercise are astonishing.
Getting your heart rate up increases the blood flow through your arteries, promoting the production of nitric acid. Nitric acid helps repair blood vessels and keep them elastic. That helps to improve aerobic fitness, which is hugely important as we age–older adults who can cover 365 metres in a six-minute walk are half as likely to die in the next decade as those who can’t.
Exercise reduces chronic inflammation, reduces stress, and thus reduces the risk of heart disease, cancer, diabetes and mental illness. It also wards off dementia through increased blood flow to the brain, and by keeping the brain active in coordinating our limbs and navigating (which is much harder than we make it look).
The bottom line?
There is no magic in the 10,000 step figure, but it is still a good target. The only dangerous levels of exercise are ‘couch potato’ and ‘This hurts so much I want to die’. As long as you are elevating your heart rate and making your brain work you are doing yourself good–and as always, the best exercise is an exercise that you will keep doing.
Disclaimer: Shane Budden is not a Doctor, and this is not intended as medical advice. The material above was sourced from New Scientist Magazine archives, and in particular New Scientist, 15 June 2019 No 3234. Before commencing any exercise regime, please consult your GP.