Validity And Reliability Of The Ymca Submaximal Cycle Test Using An Electrically-braked Ergometer

Abstract

PURPOSE: Electrically-braked ergometers allow a consistent power output regardless of variances in pedaling cadence. The present study sought to test the effect of using an electrically braked ergometer on the validity and reliability of the YMCA submaximal cycle test. METHODS: 22 male and 13 female subjects (19 - 31 y) completed one maximal treadmill test and four submaximal cycle tests (using the YMCA protocol) to measure and estimate VO2max, respectively. The submaximal trials consisted of two tests performed using a friction-braked ergometer (Monark) and two using an electrically-braked ergometer (Viasprint). All measured and estimated VO2max values were compared using repeated measures ANOVA and post-hoc tests using paired t-tests. Paired t-tests were also used to determine potential differences between repeated submaximal trials using the same ergometer. Pearson correlation coefficients were used to determine validity and reliability coefficients. RESULTS: The treadmill VO2max protocol yielded markedly higher (P < 0.05) values (50.3 ± 7.7 mL/kg/min) than the YMCA submax protocol using the friction-braked (40.8 ± 5.5 mL/kg/min) and electrically-braked ergometer (38.8 ± 4.5 mL/kg/min). Furthermore, estimated VO2max using the friction-braked ergometer was higher (P < 0.05) than that observed using the electrically-braked ergometer. There were similar reliability coefficients for the friction-braked (R = 0.63) and electrically-braked (R = 0.52) ergometers. Lastly, a moderately strong (R = 0.74) relationship was observed between actual VO2max and prediction error (VO2max- estimated VO2max). CONCLUSIONS: Both Monark and Viasprint ergometers underestimated VO2max in a sample of fit, young individuals. The magnitude of underestimation was greater in individuals with higher VO2max values. Using an electrically-braked ergometer did not improve either validity or reliability of VO2max estimates from the YMCA protocol.