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Microneurographic recordings of muscle sympathetic nerve activity (MSNA) are generally analyzed over discrete epochs, usually in minutes. This is sufficient for determining resting sympathetic outflow but may obscure physiologically relevant information regarding temporal changes during an acute stress, such as exercise. To address this limitation, we applied a moving average to examine continuously the effects of one-leg cycling on MSNA in 22 participants with (n=11) and without (n=11) heart failure with reduced ejection fraction (HFrEF). MSNA burst frequency and incidence were acquired over an 8 minute period: 2 minutes of baseline, zeroload cycling, moderate intensity cycling (50% of VO2 peak), and recovery. MSNA was analyzed in 30 second epochs, advancing in five-second increments to create a 91 point overlapping moving average plot. Area under the curve analysis demonstrated that both MSNA burst frequency and incidence were higher in HFrEF than controls during zeroload and moderate intensity cycling ...

The arterial baroreflex is important for buffering blood pressure (BP) responses to stress. Whether the sensitivity of the arterial baroreflex (BRS) is associated with hemodynamic responses to ment...

In light of the known modulatory effects of estrogen on neurohumoral control of blood pressure (BP), we tested the hypothesis that muscle sympathetic nerve activity (MSNA) and serum renin angiotensin aldosterone system (RAAS) levels would differ between estrogen deficient physically active women with functional hypothalamic amenorrhea (ExFHA) and eumenorrheic estrogen replete women. MSNA, serum RAAS components (renin, angiotensin II and aldosterone), and brachial artery BP (mmHg) were recorded at baseline and during graded lower body negative pressure (LBNP; -10, -20, and -40mmHg) in 17 recreationally active eumenorrheic women (ExOv; 24±1 years; body mass index 20.9±0.5kg/m2; mean±SEM) and 12 ExFHA women (25±1 years; 20.7±0.7 kg/m2). At baseline, heart rate (HR; b/min) and systolic BP (SBP) were lower (p0.05) between the groups. In response to graded LBNP, HR was increased (p