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

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-2 max 54.23 +/- 9.31 mlO(2)/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.