Coronavirus emergency ha imposed the implementation of strict rules and guide lines, hygienic, such as washing often the hands with water and soap for a minute, not touching the face with dirty hands or using disinfectant solutions with at least 60% alcohol, but also social distancing. In particular, what is required, is that people maintain a minimum distance between each other of at least 2 meters. However, according to scientists, this safe distance of 2 meters is valid for people that are standing still, what happens in case of people who walk, run or ride a bike? An article, still in preprint, this means that it has not yet been published, written by Belgian and Dutch researchers, try to shed some light (Blocken et al, 2020).
Coronavirus and the role of slipstream
The point is that when we move, a slipstream is formed behind us that captures salivary droplets that we emit by sneezing, coughing or simply exhaling. The researchers have studied the behavior of this slipstream by using the aerodynamic rules and the wind tunnels. What’s emerged is that the risk of virus exposition increases when we walk, run or ride a bike at reduced distances, that are intended even 1 or 2 meters, and in line with other persons who, at the same way, walk, run or ride a bike.
Coronavirus, walking and running, what do scientists suggest
But be careful, scientists aren’t saying that walking and running increase the risk of being infected by novel coronavirus. What is stated is that, instead, in order to do physical activity in a safe way, people should put into effect one of these two actions. Either by avoiding to stay in line, one behind the other, but side by side with the safe distance of 2 meters. Or in line but by increasing social distancing, in particular, for walking the safe distance is considered about 5 meters, for running 10 meters and for riding a bike 20 meters.
Coronavirus, limitations of the study
What is important to say is that the study hasn’t yet been published but is in preprint, this means that it has not yet been evaluated by a committee of experts. Moreover, the study doesn’t take into account the wind, that may increase the social distancing between people, and the smaller droplets. In any case, it is for sure very useful in order to understand that in some conditions and for more security it could be good to increase the social distancing.