18 Julio 2017 10:21
Is yours a nation of loafers or roamers? This map will give you a clue
'Walking through the city has become a subversive act,' said writer Iain Sinclair in his interview with PlayGround. Carlos Dora, coordinator of Public Health and the Environment at the WHO, recently told El País, 'Urban planning across the world is designed for cars; people don't matter.' Both these quotes sum up the feeling that walking through many Western cities, for the pedestrian, getting around is getting harder. And we're getting lazy.
This issue is at the heart of a study by researchers at the University of Stanford seeking to discover which countries are the most and least physically active in the world. And they carried out their investigation by counting steps.
Researchers used a smartphone app to count the steps of 717, 527 people in 111 countries. The information provided by this virtual pedometer – which also included the age, gender, height and weight of each user – was collected for an average of 95 days per person. This resulted in a total of 68 million days of physical activity under examination. All of this data went into the creation of a global map of physical activity, revealing the number of steps taken each day by the citizens of each country.
China stands out as the most active country of all. If we look more closely at the exact figures we can see that the inhabitants of Hong Kong are those who walk the most: 6,880 steps a day. They are followed by Ukrainians, Japanese and Russians: all good walkers. Spain is the most active Western European country, with 5,936 steps a day on average.
At the other end of the scale, the least physically active people are from the Persian Gulf countries (Saudi Arabia, Qatar, United Arab Emirates) and Southeast Asia (India, Malaysia, Philippines). Indonesia is the least active country of all, with just 3,513 steps a day. South Africa is the African nation which walks least. Brazil (4,289 steps), Greece (4,350), New Zealand (4,582), Mexico (4,692) and Portugal (4,744) are some of the 'laziest' Western nations.
There's a reason for the quotation marks around the word 'lazy': the figures published in the study do not reflect the impact of variables such as the geography of the environment, ease of pedestrian access, or the demands of climate, economics and security.
There are also some biases in the study's design.
The first and most fundamental flaw is that the data is taken from an app (Argus) that does not come preinstalled on any phone. It can be assumed that people who download and install a pedometer app have a certain predisposition to perform more physical activity and are not necessarily representative of the entire population. Furthermore, for some reason researchers limited their study to iPhone users.
It's also worth remembering that walking is just one of many possible indicators. The study doesn't take into account more static physical activities – all those hours spent working out at the gym or swimming – or the fact that in many places people are more likely to cycle than they are to walk.
Nonetheless, the researchers believe that their study – apparently the biggest ever undertaken on human movement – presents indicators that are useful for the design of future public health and urban planning policies.
That assertion is based on more than a simple step count. In their data analysis, researchers found a second indicator that can predict the prevalence of obesity within a population more accurately than daily physical activity. It's what they call 'activity inequality', or the difference in activity levels between the most and least active people in each country.
'If you think about some people in a country as "activity rich" and others as "activity poor", the size of the gap between them is a strong indicator of obesity levels in that society,' explains Scott Delp, one of the authors of the study, in an article for Stanford University's webpage.
Of the 46 countries that provided data for at least 1,000 people, the five with highest levels of 'activity inequality' are Saudi Arabia, Australia, Canada, Egypt and the United States.
Nations with the smallest gap between the 'step-rich' and the 'step-poor' include China, Sweden, South Korea, the Czech Republic and Japan.
What the study found is that people in countries with higher levels of activity inequality are 196% more likely to be obese than citizens of nations with a more equal distribution of physical activity.
The activity inequality index reveals another piece of data: the powerful role played by gender in these country-to-country differences.
'When activity inequality is greatest, women’s activity is reduced much more dramatically than men’s activity, and thus the negative connections to obesity can affect women more greatly,' said Jure Leskovec, a computer scientist who co-authored the study with Delp.