Courtney Dauwalter: Step inside the ‘pain cave’, where rules are remade. “sparked questions, debate and research into whether ultra-endurance distances might be among the only sporting arenas where the playing field between the sexes is effectively levelled.” Fascinating.

Unusual units – Dirac Due to his laconic style, the Cambridge colleagues of Nobel-prize winning physicist Paul Dirac are said to have defined one Dirac as a rate of speaking equal to one word per hour.

Knife: Meditations After an Attempted Murder, by Salman Rushdie (AB). Courageous, personal and honest. Elegant as always. 4.5/5