A Doppler Ultrasound Method to Measure Vascular Responses to Walking

Figure 1:. A) The 3D printed bracket used to fasten the ultrasound probe over the participant’s femoral artery, B) the bracket placed on the ultrasound probe, C) illustration of our experimental protocol. Participants walked on a 0° slope first, then a −5° and 5° slope in random order for 10 minutes each at 1.2 m/s.

Figure 2:. Baseline (left column) and post-walking (right column) Femoral Artery Diameter, Blood Flow Velocity, And Leg Blood Flow across walking conditions. Baseline values are 30-second averages during the baseline ultrasound measurement. Recovery time series data points are 2.5 second averages of the filtered data. Shaded regions around the mean time series are one standard deviation.

Figure 3:. Thirty second pre- and post-walking A) Femoral Artery Diameter, B) Blood Flow Velocity, and C) Leg Blood Flow. Connected circles are individual participant data. Femoral artery dilation was not significantly different across walking conditions. Incline walking caused the greatest change from rest in blood flow velocity and leg blood flow. Bars are mean ± 1 standard deviation. Brackets connecting groups of bars denote significantly different changes in variable being plotted (post minus pre-walking) between walking conditions.

Figure 4:. Leg Blood Flow Recovery Time for all walking conditions. Incline walking resulted in the greatest Leg Blood Flow Recovery Time. Horizontal lines denote significant pairwise differences in Leg Blood Flow Recovery Time. Bars are mean ± 1 standard deviation. Filled circles are individual participant data (n=13). Brackets connecting bars represent significantly different pairwise comparisons.