title: Prediction of Lunar- and Martian-Based Intra- and Site-to-Site Task Performance.
abstract: BACKGROUND
  This study aimed to investigate the feasibility of determining the physiological parameters associated with the ability to complete simulated exploration type tasks at metabolic rates which might be expected for lunar and Martian ambulation.
  
  
  METHODS
  Running V̇O2max and gas exchange threshold (GET) were measured in 21 volunteers. Two simulated extravehicular activity field tests were completed in 1 G in regular athletic apparel at two intensities designed to elicit metabolic rates of ∼20.0 and ∼30.0 ml · kg(-1) · min(-1), which are similar to those previously reported for ambulation in simulated lunar- and Martian-based environments, respectively.
  
  
  RESULTS
  All subjects were able to complete the field test at the lunar intensity, but 28% were unable to complete the field test at the Martian intensity (non-Finishers). During the Martian field test there were no differences in V̇O2 between Finishers and non-Finishers, but the non-Finishers achieved a greater %V̇O2max compared to Finishers (78.4 ± 4.6% vs. 64.9 ± 9.6%). Logistic regression analysis revealed fitness thresholds for a predicted probability of 0.5, at which Finishing and non-Finishing are equally likely, and 0.75, at which an individual has a 75% chance of Finishing, to be a V̇O2max of 38.4 ml · kg(-1) · min(-1) and 40.0 ml · kg(-1) · min(-1) or a GET of 20.1 ml · kg(-1) · min(-1) and 25.1 ml · kg(-1) · min(-1), respectively (χ(2) = 10.2). Logistic regression analysis also revealed that the expected %V̇O2max required to complete a field test could be used to successfully predict performance (χ(2) = 19.3).
  
  
  CONCLUSIONS
  The results of the present investigation highlight the potential utility of V̇O2max, particularly as it relates to the metabolic demands of a surface ambulation, in defining successful completion of planetary-based exploration field tests.
authors.affiliation: Kansas State University, Manhattan, KS, USA.
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Ade
authors.forename: Ryan M
authors.initials: RM
authors.lastname: Broxterman
authors.forename: Jesse C
authors.initials: JC
authors.lastname: Craig
authors.forename: Susanna J
authors.initials: SJ
authors.lastname: Schlup
authors.forename: Samuel L
authors.initials: SL
authors.lastname: Wilcox
authors.forename: Steve
authors.initials: S
authors.lastname: Warren
authors.forename: Phillip
authors.initials: P
authors.lastname: Kuehl
authors.forename: Dana
authors.initials: D
authors.lastname: Gude
authors.forename: Chen
authors.initials: C
authors.lastname: Jia
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Barstow
mesh_terms: D000328:Adult; D018478:Extravehicular Activity / Q000502:physiology*; D005240:Feasibility Studies; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D018535:Mars; D016081:Moon; D010101:Oxygen Consumption; D010809:Physical Fitness; D018561:Space Simulation; D013647:Task Performance and Analysis; D055815:Young Adult