There’s a magic number. Not even scholars can explain where it came from or who invented it. These are the 10,000 steps per day that many activity trackers consider as the minimum threshold of physical activity to be completed every day to stay in shape. If you use one of these devices you already know that some days you do 15,000 and others 8,000, so you are more or less “in order”. But this is true for those aged between 12 and 75 years (to find a higher threshold, for many could be 70 years, for others 80 years) because those who are older can find it really difficult to take 2000 steps a day.
This magic number is also repeated by international health organizations but, once again, we do not know who invented it. It has the charm of a number: it communicates security and is unequivocal: if you are below that threshold, it is not good, if you exceed it, it is good. Like all numbers, however, it also tends not to consider the differences between people, including ages.
A different threshold
I-Min Lee is an epidemiologist who studies how physical activity can slow down aging processes, decreasing mortality rates. She conducted a study of 16,741 women aged between 62 and 101 years. Without going into the merits of the individual results, he was intrigued by one fact: more than 7,500 steps a day, whether the subjects were performing more or less intense physical activity did not have repercussions on their mortality. Those who walked little were more exposed to mortality and those who walked more were less so. Over 7,500 steps, however, the percentages flatten out, indicating that it does not matter to run or walk to do good to your body: just count walking.
Another study has shown that it is not only the number of steps per day that matters, but above all the intensity with which you walk. Brisk walkers have proven to be less exposed to premature mortality. At this point it is worth noting that there is a difference between “fast walking” and intense activity. “If walking fast is good for you – it is fair to observe – then running must be good for you! In truth, things are a bit more complex: intense activity also has its drawbacks, first of all greater exposure to accidents. It is quite rare to get hurt by walking, even quickly. But, by now it’s well established, but it does very well.
How fast is it?
Walking expeditiously is defined by health authorities as walking at a pace that allows you to talk but not to sing. In numerical terms, these are 100 steps per minute which, in order to reach an optimal threshold of 4,400 steps per day, are transformed into 44 minutes per day of sustained walking. The American health authorities set this threshold at 2.5 hours of light exercise per week or 75 minutes of intense exercise. All nice numbers and nice definitions, don’t you think? They have only one flaw: the word “exercise” is involved and since psychology also wants its part, scholars have realized that many people are annoyed or demotivated by the fact that they think they have to do something as tiring as physical exercise.
For this reason they have understood that it is better to use a euphemism: no more “exercise” (which mentally projects you into the gym, covered with sweat and torn) but “physical activity”. Which on closer inspection is a broader definition that includes any type of movement: walking, taking stairs, walking in the mountains, parking 500 meters from the office, calling standing, etc..
Another aspect highlighted by this research concerns more common sense and tries to dismantle even a myth that persists: that training a lot and expecting and overcoming always is a good thing. Perhaps it can do well to your psyche because it shows that you are in control but it can also have important and serious relapses on the body (injury, hyper-workout, demotivation if you do not get results). Instead, you need to have a more relaxed attitude: recognizing that we are made to move, knowing that movement helps to combat depression (it does not solve it, it does not defeat it but helps) and makes you think better.
Without stress, but with the conviction that moving is good, anyway and always. And to do so, above all!