One day when we were deep in the red zone, I happened to bump into (in the literal sense of the term) a young man wearing two face masks and a scarf around his neck, who was so busy scrutinising the pedometer he held in his hand that he inadvertently walked straight into me. After he apologised, I couldn’t resist the temptation to ask why he was behaving in such a strange way. “If I’m walking I need to wear a FP2 face mask, if I walk fast a surgical mask is good enough, and if I run I can make do with a scarf. But how do I know if I am walking slowly or quickly, or whether I am almost running?”.
