Noakes, a sports medicine researcher at the University of Cape Town in South Africa, draws on what little study there has been in performance-enhancing drugs, including some just-revealed data compiled by the former East Germany.

FORBES: The Athlete's Pharmacopeia

In a recent study, economists at the IMF analysed the respective impact of deficit reduction, global rebalancing and productivity-enhancing structural reforms on the growth prospects of big rich economies and found that by far the strongest positive effect came from structural reforms.

ECONOMIST: A better way