Reproducibility and Variability of the Conconi Test Analysis

Abstract

Abstract: The Conconi test is an incremental exercise test characterised by stages of equal work. For analysis PO (power output) and HR (heart rate) are used. The deflection point of the HR/PO graph marks the point where the linear relation between PO and HR changes to a curvilinear one. HR at deflection point correlates with the anaerobic threshold. The objective of this study was to evaluate the reproducibility of HR at deflection point of tests in cycling. In literature, only one study with tests in running examined the reproducibility of the Conconi test. Nineteen trained subjects performed 4 Conconi tests on an electronically breaked cycle ergometer on different days. Finally, 68 graphs of the PO/HR relationship were analysed by computer software as well as by three different observers. HRs at deflection point of the 4 Conconi tests of every subject were compared and coefficients of variation (CVs) were calculated. Mean CVs of HR at deflection point per subject were 3.36% for the computer program and for the three observers 2.99%, 2.51% and 2.53%, respectively. CVs below 3.5% represent a good reproducibility. The agreement between the three observers was statistically good with an ICC (intraclass correlation coefficients) of 0.828. The mean range of HR at deflection point per Conconi test comparing the three observers was 4.5 bpm corresponding 2.7% of HR at deflection point.