Assessment of the accuracy of the Conconi test in determining gas analysis anaerobic threshold

The primary objective of this study was to assess the validity of the Conconi method of assessing anaerobic threshold (AT). Twenty-two competitive cyclists (11 men, 11 women) performed an incremental, maximal oxygen uptake (Vdot;o(2)max) test on an electrically braked cycle ergometer. AT was assessed by a nonlinear increase in the carbon dioxide to oxygen consumption ratio (V-slope method). AT was also measured by a computer-assessed break point in heart rate from linearity (Conconi method). Mean values for heart rate at AT were 157.3 and 163.3 b x min(-1) for the Conconi and V-slope methods, respectively. Although there was no significant difference (t = 1.07, p = 0.30) in the 2 methods, a rather low correlation coefficient (r = 0.458), high standard error of estimate (SEE = 10.7 b x min(-1)), and high total error (TE = 16.7 b x min(-1)) would preclude the use of the Conconi method as a practical tool for assessing AT.