Mechanical and metabolic reflex activation of the sympathetic nervous system in younger adults with metabolic syndrome

AimBased on reports of exaggerated blood pressure responses to whole-body exercise in patients with metabolic syndrome (MetSyn), we tested the hypothesis that MetSyn adults would exhibit augmented sympathetic and pressor responses to mechanoreflex and metaboreflex activation when compared with healthy, age-matched control subjects.MethodsWe studied 12 adults with MetSyn (34 ± 3 years) and 12 healthy control subjects (34 ± 3 years). Heart rate (HR; ECG), blood pressure (BP; finger photoplethysmography), and MSNA (microneurography of the peroneal nerve) were measured during: (1) static handgrip exercise at 15% of maximal voluntary contraction (MVC), and (2) static handgrip exercise at 30% MVC to fatigue, followed by post-exercise ischemia (PEI). Increases in MSNA, HR, and BP were assessed.ResultsDuring static exercise at both 15 and 30% MVC, increases in MSNA, HR, and BP were not different between groups. MSNA remained significantly elevated from baseline during PEI and responses were not different between groups.ConclusionSympathetic and pressor responses to mechanoreflex and metaboreflex activation are not augmented in younger adults with MetSyn.