The intermodal reliability of regulating exercise intensity using ratings of perceived exertion

• Main Author: Burkhart, Tami L.
• Other Authors: Whaley, Mitchell H.
• Format: Others
• Published: 2011
• Subjects: Exercise > Evaluation.; Aerobic exercises > Testing.; Exercise tests.; Exercise > Equipment and supplies > Reliability.; Exercise > Physiological aspects.
• Online Access: http://cardinalscholar.bsu.edu/handle/handle/186629; http://liblink.bsu.edu/uhtbin/catkey/1136711

The purpose of this study was to evaluate the intermodal reliability of perceptually-based exercise intensity among four machines: Treadmill (TM), Stationary cycle (CB), Body Trec elliptical arm/leg (BT), and AirDyne (AD). Nineteen subjects (8 male and 11 female; age 44 + 12 yrs) completed one GXT on each of the machines, following a mode-specific protocol. Subjects also completed two 15 minute production trials (PTs) on each machine at self-selected workrates corresponding to target RPEs of 11-12 (L) and 15-16 (H). In the PTs, workloads were self-adjusted through the first 5 minutes and then remained stable for the rest of the trial. Modes were randomly assigned, and subjects were blinded to the workload throughout each trial. Heart rate (HR) and oxygen uptake (V02) were obtained during the final 5 min. of each trial using a Polar HR monitor and Aerosport TEEM 100. Also, blood lactate (BLC) was sampled immediately following exercise at each intensity. Intermodal reliability was assessed using ANOVA, intraclass correlations (R), coefficients of variation (CV), and mean absolute differences for HR, V02, and BLC during the second PT. ANOVA revealed nointeraction for BLC at either the LOW or HIGH. Post -hoc analysis showed the TM and/or BT to produce significantly higher physiological responses at both intensity levels. At the L and H, intermodal Rs were: HR (.84/.88), VO2 (8/.77) and BLC (0.09/0.67). Significant intrasubject differences were observed at the L for HR (11-47bpm, VO2 (.04-1.46 L/min), and BLC (.29-12.94 mM/L). The H trials followed a very similar trend. Using a HR criteria of +2 beats/15 sec. to assess intrasubject reliability, 0% of the subjects were reliable at both the L and H. This data suggests that perceptually-based exercise across multiple modes is associated with significant intraindividual variability, and reliability is dependent upon the statistical design and physiological variable being used. In conclusion, it is recommended that extensive exercise testing be performed to ensure that individual participants can reliably use the RPE scale, prior to using an RPE value to prescribe the intensity of exercise. === School of Physical Education