Ergometry Individual working capacity was calculated as a percentage of the predicted (=100% work load) Watt value (derived from the tabulation, standardized for sex, age, and body surface [28]). Briefly, the workload was increased every two minutes in steps of 25 W, beginning with 25 W and going on until the point of exhaustion (Ergoline, Ergometrics 900). The individual physical working capacity (PWC) was expressed as the individual maximal power (Watt)max in percent of a reference value (Wattref): PWCind = 100 x Wattmax/Wattref [28].