If you have a gym pass or access to a treadmill, here is an experiment to try with caution – or, safer still, restrict it to a thought experiment. Put the speed up to a whisker under 12 miles per hour – assuming, of course, that it lets you, as many home treadmills don’t dare go that fast. And then run for your life, preferably with a big pile of pillows behind for when you fly off the back.
Now imagine sustaining that pace for 26.2 miles. Because that is the speed at which the Ethiopian athlete Tigist Assefa destroyed the women’s world marathon record in Berlin, taking more than two minutes off the previous record and finishing in 2 hours 11 minutes and 53 seconds.
