Validation of an equation for predicting energy cost of arm ergometry in women

Abstract

Few studies have examined the validity of metabolic equations for the prediction of energy cost (VO₂) of arm ergometry in women. Therefore, the purpose of this study was (a) to compare directly measured and predicted VO₂ values using the American College of Sports Medicine (ACSM) equation and (b) to develop and validate a prediction equation for women. A sample of 60 female subjects with mean (±SD) age, weight and height 26.5±14.4 years, 61.5±7.6 kg, 163.3±6.0 cm, respectively, was randomly assigned to an equation group (N = 40) and a cross validation group (N = 20). All subjects performed an incremental arm ergometry test (10 W increases every 2 min), until termination criteria were met. Repeated measures ANOVA indicated significant differences between the measured VO₂ and ACSM predicted VO₂ during all the incremental test work rate. Multiple linear regression analysis was used to develop the following upper body exercise VO₂ prediction equation:

$${\text{VO}}_2 ({\text{ml}}\cdot {\text{kg}}^{- 1}\cdot {\text{min}}^{ -1}) = 23.461 - (0.272 \times {\text{Body}}\;{\text{Weight)}} + (0.403 \times {\text{watts)}}\quad [R^2 = 0.82,\;{\text{SEE}} = 2.79]$$

Cross validation indicated lower variability using the current prediction equation. An additional independent sample of 13 subjects performed a 30-min steady-state test at 40% of their pre-determined maximal work rate. VO₂ measured during the 30 min steady-state test (was significantly different P < 0.05) from the ACSM prediction at all time intervals. There were no significant differences using the above equation following the 5 min time interval. Therefore, a new equation is proposed as a means of providing a gender-specific energy cost prediction equation.