Relationship between simulated extravehicular activity tasks and measurements of physical performance

The purpose was to evaluate the relationships between tests of fitness and two activities that simulate components of Lunar- and Martian-based extravehicular activities (EVA). Seventy-one subjects completed two field tests: a physical abilities test and a 10 km Walkback test. The relationships between test times and the following parameters were determined: running VO2max, gas exchange threshold (GET), speed at VO2max (s-VO2max), highest sustainable rate of aerobic metabolism [critical speed (CS)], and the finite distance that could be covered above CS (D'): arm cranking VO2peak, GET, critical power (CP), and the finite work that can be performed above CP (W'). CS, running VO2max, s-VO2max, and arm cranking VO2peak had the highest correlations with the physical abilities field test (r = 0.66-0.82, P < 0.001). For the 10 km Walkback, CS, s-VO2max, and running VO2max were significant predictors (r = 0.64-0.85, P < 0.001). CS and to a lesser extent VO2max are most strongly associated with tasks that simulate aspects of EVA performance, highlighting CS as a method for evaluating astronaut physical capacity. (C) 2014 Elsevier B.V. All rights reserved.