Fig. 2.
Hemodynamic responses. Shown are mean arterial pressure (MAP), heart rate (HR) in beats/min (bpm), left ventricular volumes (LVVs), cardiac output (CO), and nonischemic vascular conductance (NIVC) responses during rest, mild exercise (Ex), and mild exercise with muscle metaboreflex activation (Ex+MMA) settings in control (solid bars) and α1-adrenergic blockade conditions (hatched bars). All parameters showed significance across workload settings, as well as significance between control and prazosin conditions (P < 0.05), with the exception of stroke volume and left-ventricular end-systolic volume (which were only significant across workload settings). All parameters had a significant interaction between the 2 independent variables, with the exception of left ventricular end-systolic volume. *Between 2 bars, signifies a significant pair-wise comparison (P < 0.05). †Significant increase from the previous setting. ♣Above a specific setting, signifies a significant pair-wise comparison in left ventricle stroke volume (P < 0.05). ‡Significant increase in left ventricular end-diastolic volume. #Significant increase in stoke volume from the previous workload (P < 0.05). *Next to bracket, indicates a significance between left ventricular end-systolic volume across workloads but not between control and α1-adrenergic blockade conditions.