Document Type : original article
Abstract
aim: The purpose of this study was to develop and investigate the accuracy of regression equation to predict VO2max and
estimate cardiorespiratory fitness (CRF) based on non-exercise (N-EX) data in adult women. Research Methodology: In
order to achieve the purpose of research, 30 female students studying at Kharazmi University, Tehran; Iran, with the
average age 24.96±2.41 yr., weight 57.07±7.08 kg, and height 162.55±5.15 cm were selected as the research sample. At
first, the subjects filled in the consent for participation in research form and revised physical activity readiness
questionnaire (rPar-Q). The N-EX data were collected just before the maximal graded exercise test (GXT)included the
participant’s age, body mass index (BMI), perceived functional ability (PFA) to walk, jog, or run given distances, and
current physical activity (PA-R) level. Then, all participants (N = 30), aged 18-30 years old, successfully completed a
Bruce maximal GXT on treadmill using gas analyzer to assess VO2max.The data were analyzed by multiple linear
regression, ANOVA R.M, Pearson correlation, cross validation using predicted residual sum of squares (PRESS), and
LSD post hoc test statistical methods. Results: The data analysis revealed a high correlation, minimal shrinkage and
difference; thus, Jackson, George and Bradshaw regression models yield relatively accurate results and are a convenient
way to predict VO2maxand estimate CRF in adult women (18-30 yr.).In order to predict VO2max and estimate CRF in adult
women, the three new regression equations (Ghafari-Jackson, Ghafari-George, and Ghafari-Bradshaw models) should
yield acceptable accuracy when applied to an independent sample of adult women (aged 18-30 yr.) with a similar
cardiorespiratory fitness level. It should be mentioned that non-exercise regression equations are not as accurate as gas
analyzer criterion test and cannot be used instead of this criterion test. But they would predict VO2max and estimate CRF in
adult women accurately if they were used correctly and can be used instead of Bruce treadmill equation criterion test.
Conclusions: The new established regression equations or the old developed ones are safe and quite accurate, easy, fast,
and inexpensive for large groups, elders, and persons with cardio-vascular diseases.
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