*2.1. Sample*

None of the participants withdrew their consent, and none had to be excluded. Eighteen healthy adults (females = 11; mean age 25 ± standard deviation (SD) 2 years; body mass index 22.1 ± 1.8 kg/m2) were included.

### *2.2. Blood Flow Velocity*

The blood flow velocity in the A. poplitea was significantly reduced by wearing the BFR cuff (compared to unrestricted, *p* = 0.002; mean intraindividual difference: −7.6 cm/s, −14%, Figure 1).

**Figure 1.** Blood flow velocity in the A. poplitea: (**<sup>a</sup>**,**b**) Representative original Doppler sonography blood flow profiles at rest: The upper images show the region of interest of the A.poplitea; the lower diagrams show the time course on the x-axis and the blood flow velocity heartbeat by heartbeat on the y-axis. (**a**) Blood flow velocity without wearing a cuff. (**b**) Blood flow velocity while wearing the cuff (occlusion pressure 300 mm Hg). (**c**) Boxplots of the grouped pre-post differences in blood flow velocity with and without cuff. Data are displayed as median and inter-quartile ranges plus range (whiskerbars).
