Cross-validation of the recumbent stepper submaximal exercise test to predict peak oxygen uptake in older adults

Abstract

Background. Submaximal exercise testing can have a greater application in clinical settings because peak exercise testing is generally not available. In previous work, a prediction equation was developed to estimate peak oxygen consumption (Vo2) using a total body recumbent stepper (TBRS) and the Young Men's Christian Association (YMCA) protocol in adults who were healthy. Objective. The purpose of the present study was to cross-validate the TBRS peak Vo2 prediction equation in older adults. Design. A cross-sectional study was conducted. Methods. Thirty participants (22 female, 8 male; mean age=66.8 years, SD=5.52; mean weight=68.51 kg, SD=13.39) who previously completed a peak exercise test and met the inclusion criteria were invited to participate in the cross-validation study. Within 5 days of the peak Vo2 test, participants completed the TBRS submaximal exercise test. The TBRS submaximal exercise test equation was used to estimate peak Vo2. The variables in the equation included age, weight, sex, watts (at the end of the submaximal exercise test), and heart rate (at the end of the submaximal exercise test). Results. A strong correlation was found between the predicted peak Vo2 and the measured peak Vo2. The difference between the values was 0.9 mL·kg-1·min-1, which was not statistically different. The standard error of the estimate was 4.2 mL·kg-1·min-1. Limitations. The sample included individuals who volunteered to perform a peak exercise test, which may have biased the results toward those willing to exercise to fatigue. Conclusion. The data suggest the TBRS submaximal exercise test and prediction equation can be used to predict Vo2 in older adults. This finding is important for health care professionals wanting to provide information to their patients or clients regarding their fitness level. © 2014 American Physical Therapy Association.