As a part of the space-research program, a physiologist was asked to investigate the effect of flight-induced stress on blood pressure. Accordingly, the blood pressure of the cosmonauts was to be measured twice: once before the take-off and once after the spacecraft entered the designated orbit around the earth. For a proper comparison, the preflight blood pressure should be recorded in
In lying position, blood flow is the same in the brain and the lower limbs. Similarly, in space, there is no gravity. So blood flow is same in the brain and the lower limbs.
The lying down position
The sitting position
The standing position
Any position, as long as the post-flight recording is made in the same position