Physiological parameters determined at OBLA vs. a fixed heart rate of 175 beats center dot min(-1) in an incremental test performed by amateur and professional cyclists

A blood lactate concentration of 4 mmol l(-1) (OBLA) is frequently used as an indicator of the maximal steady state of lactate (MLSS) for workload pla nning in training programs. The aim of the present investigation was to com pare several metabolic parameters determined at OBLA and at a fixed heart r ate of 175 beats min(-1) (HR175) in amateur cyclists (AC) and professional cyclists (PC). Sixteen AC and 22 PC performed an exercise test on a cycle e rgometer following a ramp protocol (25W min(-1), 70-80rpm) to exhaustion. G aseous exchange was monitored throughout the test. (V) over dot O-2 % (V) o ver dot O-2max max, and power output (W) corresponding to OBLA and HR175 we re determined and mean values compared using a Student's t-test. Findings i ndicated higher (V) over dot O-2max,a and W in general in PC (p<0.01), and higher (V) over dot O-2 and W at OBLA and HR175 in PC (p<0.01). No signific ant difference was found between values determined at OBLA and HR175 in the AC group, while in the PC group, (V) over dot O-2, %(V) over dot O-2max, a nd W were higher at OBLA. These observations suggest the possible use of a fixed, reference HR of 175 beats min(-1) to determine the exercise intensit y corresponding to OBLA in amateur cyclists. This was not the case for the professional cyclists.