=+34. The article “Validation of the Rockport Fitness Walking Test in College Males and Females” (Research Quarterly for Exercise and Sport, 1994: 152–158)

recommended the following estimated regression equation for relating y 5 VO2max (L/min, a measure of cardiorespiratory fitness) to the predictors x1 5 gender (female 5 0, male 5 1), x2 5 weight

(lb), x3 5 1-mile walk time (min), and x4 5 heart rate at the end of the walk (beats/min):

yn 5 3.5959 1 .6566x1 1 .0096x2 2 .0996x3 2.0080x4