After landing on Earth form a 7 day space flight Wubbo Ockels wrote this....
"I stood up and it was frightening. For a few seconds I felt that I had just stepped into an elevator going up at an incredible speed. All my thoughts about my perception of gravity came back immediately. I just perceived it as real acceleration! What does this gravity do to us? We are all so used to it that it must give us a distorted view. We cannot escape it. The first few nights I woke up several times, switched to acceleration, the bed was pushing me upward, speed was building up. Then I switched back to the force feeling. I was tied down by my hands and feet.
Somehow suddenly this unavoidable gravity, its incredible speed and the continuous passage of time seemed to fit together naturally. Time, seen as necessary for experiencing change, to come alive. "
I thought it was interesting and somewhat relevant...