Validity and reliability of the YMCA submaximal cycle test using an electrically braked ergometer

Purpose: 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 ages 19 to 31 completed one maximal treadmill test and four submaximal cycle tests to measure and estimate VO2max, respectively. The maximal tests involved recording heart rate and VO2 during graded exercise until volitional fatigue; an actual max was verified when two out of the following criteria: respiratory Exchange Ratio \u3e 1.1, VO2 plateau (\u3c 150 ml/min increase in VO2 during final stage), and achievement of 90% age-predicted HR max (or completed a validation stage). The submaximal tests were conducted in accordance with ACSM guidelines (10th ed.). Measured and predicted VO2max measurements were compared between tests using repeated measures ANOVA and Pearson correlations. Results: The treadmill VO2max protocol yielded significantly higher values (50.3 ± 7.7 mL/kg/min) than the YMCA submax protocol using a 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 than that observed using the electrically braked ergometer. There were similar reliability coefficients between 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). Conclusion: Both Monark and Viasprint ergometers severely underestimated VO2max in a sample of generally fit, young individuals. Future investigations should explore the possible relationship between higher aerobic fitness and accuracy of predicting VO2max via HR response