Effect of differences in post-exercise lactate accumulation in athletes' haemodynamics

To verify the relationship between exercise intensity and post-exercise haemodynamics, we studied haemodynamic and lactate responses during 10 min following 3 bicycle tests. Two tests were performed for 3 min at 70% and 130% of the workload corresponding to anaerobic threshold (70% W-at and 130% W-at tests), and 1 was performed until exhaustion at 150% of the maximum workload achieved during a previous incremental test (150% W-max test). During the recovery period after the 150% W-max test we observed the highest increases in blood lactate with respect to the baseline: at the 9th minute of recovery lactate concentration increased by +9.3 +/- 2.7, +6.4 +/- 3.1, and +1.1 +/- 0.9 mmol(.)L(-1) in the 150% W-max (p > 0.05 with respect to the other protocol sessions), 130% W-at, and 70% W-at tests, respectively. We also observed greater reductions in cardiac pre-load and systemic vascular resistance in the 150% W-max test than in the 130% W-at and 70% W-at tests. However, the cardiac output response successfully faced the increased vasodilatation occurring during 150% W-max test so that changes in mean blood pressure were similar in the 3 test conditions. This study shows that exercises that yielded different lactate concentrations also led to greater vasodilatation. Nevertheless, mechanisms controlling the cardiovascular apparatus successfully prevented a drop in blood pressure in spite of the cardiovascular stress.