Effects of acute sympathetic activation on the central artery stiffness after strenuous endurance exercise

Abstract

Purpose: Augmented central arterial stiffness (CAS) increases cardiovascular risk. CAS can be augmented by physical exercise and sympathetic activation (SYMP) induced by stressful stimuli. Interestingly, sympathetic vasoconstriction triggered by a sympathetic stimulant is augmented immediately after a strenuous half-marathon compared to at rest. This study assessed whether CAS also augments more post- than pre-half-marathon in response to SYMP. Such assessment takes on relevance considering the growing popularity of strenuous, long-distance endurance exercises. Methods: 13 healthy recreational runners (age 46.1 ± 6.5 years; V′O 2max 54.23 ± 9.31 mlO2/min/kg) provided the following measurements prior to and within 10 min following a strenuous half-marathon: beat-by-beat aortic pulse wave velocity (aPWV; index of CAS), mean blood pressure, and heart rate assessment. Measures were performed at rest and during a 2 min handgrip-mediated SYMP. The effects of the half-marathon and SYMP were assessed by two-way repeated-measures ANOVA. Results: Measurements of the aPWV pre- and post-race were not significantly different (7.5 ± 0.8 vs 7.8 ± 0.8 m/s, p = 0.34; pre- vs post-race). 2 min of SYMP increased the baseline aPWV post-race (7.8 ± 0.8 vs 8.4 ± 0.8, p = 0.003; rest vs SYMP) but not pre-race (7.5 ± 0.8 vs 7.9 ± 0.9, p = 0.21). Conclusion: The baseline aPWV assessed 7 to 8 min after a strenuous half-marathon is similar to that pre-race in healthy runners. This agrees with previous studies suggesting CAS being at or below resting values > 5 min following completion of aerobic exercises. The same sympathetic stressor augments CAS to a greater extent 8–10 min post-race than pre-race, suggesting a greater post-exercise stiffening of central artery segments triggered by the same task.