Accuracy of two simple methods for the assessment of health-related physical fitness.

We have developed a useful equation for estimating health-related physical fitness age. This version of health-related fitness age was developed as an extension of the biological age index and is useful for evaluation of individual differences in functional abilities of middle-aged and older adults. This measure consists of 4 independent variables fitness (VO2 max, standing trunk flexibility, %fat, and grip strength). However, direct measurement of maximal oxygen uptake (VO2 max) is an invasive clinical procedure and not practical for large scale work. In the current study, we attempted to assess the fitness age more feasibly. We selected a questionnaire method and a 12-min. submaximal treadmill walk test as substitutes for the VO2 max test. The three fitness ages were computed for 23 Japanese men (M(age) 54.7 +/- 10.7 yr.), using actual VO2 max (actual fitness age), questionnaire VO2 max (predicted questionnaire fitness age), and treadmill VO2 max (predicted treadmill fitness age). Predicted questionnaire fitness age (61.0 +/- 10.5 yr.) and predicted treadmill fitness age (60.0 +/- 12.4 yr.) were significantly correlated with actual fitness age (60.1 +/- 12.4 yr.) (r= .96 and .97, respectively). There were no significant differences among the three indices, but there was a significant difference between actual fitness age and chronological age (p<.05). For VO+/-2 max substituting the questionnaire for the treadmill estimate is acceptable in assessing fitness age and reducing the clinical risk for middle-aged and older Japanese men.