Post-exercise hypotension and reduced cardiac baroreflex after half-marathon run: in men, but not in women

We examined whether trained women exhibit similar cardiovascular and cardiac baroreflex alterations after a half-marathon compared to men. Thirteen women (39.1 ± 9.3 years; 165 ± 6 cm; 58.2 ± 7.5 kg; maximal aerobic speed (MAS): 13.7 ± 2.2 km·h-1) and 12 men (45.7 ± 10.5 years; 178 ± 7 cm; 75.0 ± 8.3 kg; MAS: 15.8 ± 2.2 km·h-1) ran an official half-marathon. Before and 60-min after, cardiovascular variables, parasympathetic (heart rate variability analysis) modulation and cardiac baroreflex function (transfer function and sequence analyses) were assessed during supine rest and a squat-stand test. Running performance was slower in women than in men (120 ± 19 vs. 104 ± 14 min for women and men, respectively). However, when expressed as a percentage of MAS, it was similar (78.1 ± 4.6% and 78.2 ± 5.4% of MAS for women and men, respectively). Before the run, women exhibited lower mean blood pressure (BP), cardiac output (CO) and stroke volume (SV) compared to men, together with higher parasympathetic indexes. After the race, parasympathetic indexes decreased in both sexes, but remained higher in women. Reduced SV, systolic BP and cardiac baroreflex were observed in men but not in women. Contrary to men, a competitive half-marathon did not trigger post-exercise hypotension and a reduced cardiac baroreflex in women.