 The test, arranged by Froome himself, took place shortly before the start of the Vuelta, on 17 August 2015, in the GlaxoSmithKline Human Performance lab in London.Several tests were carried to determine his maximum sustainable power for 20–40 minutes (threshold power), level of maximum oxygen consumption (VO2 max) and his peak power.Froome's peak power was measured at 525 W; his peak 20–40-minute power, at 419 W, corresponds to 79.8 percent of the maximum.