Using rating of perceived exertion in assessing cardiorespiratory fitness in endometrial cancer survivors

Daniel C. Hughes, Matthew G. Cox, Susan Serice, George Baum, Carol Harrison, Karen Basen-Engquist

For cancer survivors, who also often present with co-existing health conditions, exercise testing is often performed using submaximal protocols incorporating linear heart rate response for estimating the cardiorespiratory capacity and assessing exercise tolerance. However, use of beta-blocker medications, during sub-maximal protocols based on linear HR response can be problematic. Rating of perceived exertion (RPE), which takes into account an individual's overall perception of effort, can be used as a complementary tool that does not rely solely on the heart rate response to increased workload. We compared heart rate response (VO2HR) and self-rating of perceived exertion (VO2RPE) in a graded submaximal exercise test (GXT) in 93 endometrial cancer survivors. The results of the GXT were stratified according to whether participants were taking beta-blocker (BB) medications or not (non-BB). Among non-BB participants, there was no difference between the mean VO2HR and the mean VO2RPE estimates of cardiorespiratory capacity (mlO2//kg/min) (20.4 and 19.3, respectively; p = 0.166). Among BB participants, the mean VO2HR approached significant difference than the mean VO2RPE (21.7 mlO2//kg/min and 17.6 mlO2//kg/min, respectively; p = 0.087). Bland-Altman plots for both methods showed a proportional bias for the non-BB group; but not the BB group. Our results suggest that sub-maximal protocols based on Borg's Rating of Perceived exertion (RPE) produce differing results from sub-maximal protocols based on HR response when applied to clinical population taking BB medications. Using RPE instead of HR for participants on BB medications may be a better method for assessing the exercise tolerance for estimating the cardiorespiratory capacity in sub-maximal exercise testing.