title: Reliability of a 5-min running field test and its accuracy in VO2max evaluation.
abstract: BACKGROUND
  Five-min running field test (5_RFT) was established for determining individuals' maximal aerobic velocity (V(amax)) and functional aerobic capacity (VO2peak) during horizontal run. We determined the number of trials required for establishing high reliability of the 5_RFT and examined its accuracy in evaluating individuals' maximal aerobic capacity (VO2max).
  
  
  METHODS
  The V(amax)(5) recorded during the 5_RFT on four separate days was compared in 45 subjects (14 male, 31 female, 17.0+/-0.2 yrs) of various levels of physical fitness. The accuracy of VO2max evaluation using V(amax)(5) was examined via regression analysis in additional 23 male subjects (20.7+/-0.3 yrs).
  
  
  RESULTS
  The mean correlation coefficient of V(amax)(5) among four trials was 0.94. Intraclass reliability coefficient across all trials was 0.98. For trial 3 and 4, the mean value of subjects' V(amax)(5) was higher than that of trial 1 and 2. V(amax)(5) of trial 2 was also higher than that of trial 1 while no difference was found between trial 3 and 4. F-test of equality of variances demonstrated similar sample variance of V(amax)(5) in all trials. Within-subject coefficient of variation in V(amax)(5) was 3.7 percent for all trials was reduced to 2.4 percent for trial 3 vs 4. For examining the accuracy in VO2max evaluation, regression analysis revealed that the V(amax)(5) explained 35.0 percent of the variance of measured VO2max (SEE = 5.64 ml x kg(-1) x min(-1)).
  
  
  CONCLUSIONS
  The 5_RFT is reliable in determining V(amax)(5). Nevertheless, two familiarization sessions are recommended for achieving the best performance in the test. The 5_RFT cannot evaluate VO2max with reasonable accuracy in young males.
authors.affiliation: Department of Physical Education, Hong Kong Baptist University, Kowloon Tong, Hong Kong, China. tongkk@hkbu.edu.hk
authors.forename: T K
authors.initials: TK
authors.lastname: Tong
authors.forename: F H
authors.initials: FH
authors.lastname: Fu
authors.forename: B C
authors.initials: BC
authors.lastname: Chow
mesh_terms: D000293:Adolescent; D000332:Aerobiosis; D000704:Analysis of Variance; D005080:Exercise Test / Q000379:methods*; D005260:Female; D006801:Humans; D008297:Male; D010101:Oxygen Consumption; D012044:Regression Analysis; D015203:Reproducibility of Results; D012420:Running / Q000502:physiology*; D013997:Time Factors