Abstract
Recent research has provided encouraging results to support the prediction of maximal oxygen uptake (VO2max) from a perceptually regulated exercise test (PRET). Studies to date have solely investigated its application to cycle ergometry.
PURPOSE: To determine if VO2max can be predicted with acceptable accuracy and repeatability from a sub-maximal treadmill PRET.
METHODS: Eighteen volunteers (21.7 ± 2.8 years) completed three treadmill PRETs (each separated by 48hrs) and one maximal graded exercise test. Participants self regulated their exercise at RPE levels 9, 11, 13 and 15 in a continuous and incremental fashion. Oxygen uptake (VO2) was recorded continuously during each three minute bout. VO2 values for the RPE range 9-15 were extrapolated to RPE 20 using regression analysis to predict individual VO2max scores. This same procedure was also adopted to calculate estimated VO2max from treadmill speed and gradient using ACSM metabolic equations. The concordance of the predicted and actual VO2max scores and the trial-to-trial reliability of the predicted scores were analysed using intraclass correlation coefficients (ICC) and the limits of agreement (LoA) technique.
RESULTS: The mean VO2 following the last stage of the PRET (RPE 15) was 73 ± 8% of VO2max. The LoA between actual (48.0 ± 6.2 ml·kg-1·min-1) and predicted scores were 1.9 ± 13.3, 1.0 ± 8.8 and -0.6 ± 7.1 ml·kg·1·min-1 for trials 1, 2 and 3, respectively. The corresponding values from the ACSM calculations were 3.2 ± 19.8, 0.2 ± 11.9 and -0.7 ± 9.9 ml·kg·1·min-1. Reliability analysis for the PRET VO2max predictions yielded ICCs of 0.76 and 0.84 and LoAs of 0.9 ± 12.3 ml·kg·1·min-1 and 1.7 ± 8.5 ml·kg·1·min-1for trial1 versus trial 2, and trial 2 versus trial 3, respectively.
CONCLUSIONS: These findings demonstrate that, given practice, a sub-maximal treadmill PRET can yield predictions of VO2max that are acceptably reliable and more accurate than an established predictive method. Accordingly, its application in environments where maximal tests are inappropriate is worthy of further investigation.
PURPOSE: To determine if VO2max can be predicted with acceptable accuracy and repeatability from a sub-maximal treadmill PRET.
METHODS: Eighteen volunteers (21.7 ± 2.8 years) completed three treadmill PRETs (each separated by 48hrs) and one maximal graded exercise test. Participants self regulated their exercise at RPE levels 9, 11, 13 and 15 in a continuous and incremental fashion. Oxygen uptake (VO2) was recorded continuously during each three minute bout. VO2 values for the RPE range 9-15 were extrapolated to RPE 20 using regression analysis to predict individual VO2max scores. This same procedure was also adopted to calculate estimated VO2max from treadmill speed and gradient using ACSM metabolic equations. The concordance of the predicted and actual VO2max scores and the trial-to-trial reliability of the predicted scores were analysed using intraclass correlation coefficients (ICC) and the limits of agreement (LoA) technique.
RESULTS: The mean VO2 following the last stage of the PRET (RPE 15) was 73 ± 8% of VO2max. The LoA between actual (48.0 ± 6.2 ml·kg-1·min-1) and predicted scores were 1.9 ± 13.3, 1.0 ± 8.8 and -0.6 ± 7.1 ml·kg·1·min-1 for trials 1, 2 and 3, respectively. The corresponding values from the ACSM calculations were 3.2 ± 19.8, 0.2 ± 11.9 and -0.7 ± 9.9 ml·kg·1·min-1. Reliability analysis for the PRET VO2max predictions yielded ICCs of 0.76 and 0.84 and LoAs of 0.9 ± 12.3 ml·kg·1·min-1 and 1.7 ± 8.5 ml·kg·1·min-1for trial1 versus trial 2, and trial 2 versus trial 3, respectively.
CONCLUSIONS: These findings demonstrate that, given practice, a sub-maximal treadmill PRET can yield predictions of VO2max that are acceptably reliable and more accurate than an established predictive method. Accordingly, its application in environments where maximal tests are inappropriate is worthy of further investigation.
Original language | English |
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Pages (from-to) | 258-259 |
Journal | Medicine and Science in Sports and Exercise |
DOIs | |
Publication status | Published - 1 May 2009 |
Externally published | Yes |