Computerized determination of lactate threshold during three modes of exercise.

The lactate threshold (LT) and corresponding exercise levels (rate-pressure product, workload, and exercise duration) have been proposed as objective quantitative parameters of functional capacity and cardiovascular status. The purpose of the present study was to compare three modes of exercise and to evaluate the influence of the body position, using a rapid lactate analyser and computerized determination of the LT. Eight healthy male subjects were studied. No significant difference was found between the LT measured during treadmill (1.55 +/- 0.22 mmol/l), upright bicycle (1.61 +/- 0.17 mmol/l), and supine bicycle (1.41 +/- 0.05 mmol/l) exercises. However, while exercise levels corresponding to the lactate threshold were similar in running and upright bicycling, the supine bicycle was associated with lower exercise duration and workload corresponding to the LT.