Imagine that I'm jumping over an infinite cliff, under the influence of the gravitational force(F=mg, where m is my mass and g is the gravitational constant). At some point, due to the acceleration, my speed will become relativistic, and everything around should become changing. The sensation of time, distance or maybe the force itself, will not be the same. The question is: Is there a specific value of the speed that will determine the relativistic regime of my motion?