DETERMINATION OF THE HEART-RATE DEFLECTION POINT BY THE DMAX METHOD

Objective, Conconi et al, proposed that the point where heart rate dep arted from linearity in an incremental exercise test was a good indica tor of the anaerobic: threshold, However, the heart rate deflection po ints (HRDPs) can not be determined in many subjects, The aim of this s tudy was to determine the heart rate deflection point by the Dmax meth od and to compare it with the conventional linear method, Setting. The study was performed in the Exercise Physiology Laboratory in the Facu lty of Medicine, Selcuk University, Participants, Thirthy-two untraine d males (aged 18-22) performed a maximal exercise test on a cycle ergo meter, Results. The deflection from linearity of HR could not be detec ted in nine subjects (28%) by the linear method, The HRDPs could be de tected in all subjects by the Dmax method, It was observed that the HR values in the HRDPs determined by both methods were close to the maxi mal HR values (approximately 90% of maximum), There were high correlat ions and no differences (p more than 0.05) between the deflection poin ts expressed as oxygen uptake, HR and work rate determined by two meth ods (correlation coefficients 0.93, 0.93, 0.97, respectively, p less t han 0.001), Conclusions. The Dmax method is more useful than linear me thod, The HRDPs of all the people can easily and objectively be found by this method.