Compression is necessary for the blood to flow upwards against the natural downward pull of gravity. (discountsurgical.com)
Starting from scratch pad, Brodeur juggled equations dealing with gravity, air resistance and ball spin, and while his Y = 1/2 GT ¬ ¨ ¬ ® «Äö √ cents ¬ ß (in which Y stands for the downward pull of gravity on the ball from a horizontal plane, G for gravity and T for time) is not on the order of E = mc ¬ ¨ ¬ ® «Äö √ cents ¬ ß, it did prove that the fastest serve possible is 140 mph. (si.com)
While flowing upwards through the body, it faces the downward pull of gravity. (discountsurgical.com)