NASA Anthropometry and Biomechanics Research
"For purposes of this [research], body dimensions and mobility descriptions are limited to the range of personnel considered most likely to be space module crewmembers and visiting personnel. It is assumed that these personnel will be in good health, fully adult in physical development, and an average age of 40 years. A wide range of ethnic and racial backgrounds may b represented, and crewmembers may be either male or female." -NASA