Well, no. Because if two people are on the same train at the same speed, the force applied to them would not be the same, only the acceleration would. I know it's confusing but the "g force" doesn't actually refer to force but acceleration.Isn't airtime caused by the inertia force caused by the change from up to down?, so if two people on the same train at the same speed with the same change in direction had the same force acted on them the heavier would be moved less as the force would require more energy to move them
The force applied to them would be proportional to their weight so 200 lbs man would be subject to twice as much force as a 100 lbs kid. Therefore, the bigger guy would get off its seat just as hard as the smaller kid.
It's pretty similar to when you just sit on a chair, the bigger you are, the stronger the reaction of the chair is, so that whatever is your mass, you don't fall through the chair.