How to measure how stress affects athletes’ performance

How much is good for an athlete? Surprisingly, since modern, professional sport of all sorts now seems to be in the hands of number crunchers trying to extract another zillionth of a percent of from their charges, no one knows. The reason is that, to avoid decrements in performance of equal and opposite magnitude, top athletes are rarely willing to carry even the tiniest monitoring devices when in competition. And when they are not in competition such measurements would be meaningless.However, two behavioural economists, Lu Yunfeng of Nanjing University, in China, and Zhong Songfa of the National University of Singapore, think they have found a way around this—at least for athletes whose disciplines do not require them to move a lot.