Study procedures

Participants visited the laboratory on 3 separate occasions and assessment of resting heart rate (HR), BP and CBFv was recorded twice in the seated position by the same study technician. Participants arrived at the laboratory approximately the same time of day on all 3 study visits and remained seated for the duration of testing. Prior to data collection, a 20-minute period of quiet rest was provided in a thermo-neutral, dimly lit room while the participants were instrumented with three ECG electrodes, the BP cuffs were fitted to the middle finger of the right hand and secured at the left brachial artery. A head harness was placed and secured to the temporal region for TCD recording of the left MCA. After instrumentation, two 5-minute assessments of simultaneous beat-to-beat systemic and cerebral hemodynamics were recorded, which were initiated at 0 and 15 minutes after the 20 minutes of quiet rest. Manual BP was assessed once during each 5-minute data recording period.