Originally Posted by
cyccommute
Um…no. Physics. When you push down into the ground, the maximum force is your body weight. When you push from one arm into the other, you can’t exert as much force. We don’t hold floor pumps between our hands and pump tires that way because we can exert as much force as our body weight.
I don't think that's correct.
Anyone who can do a pull-up is exerting more force than their body weight.
Squeezing a pump is, of course, not a pull-up; an exercise that is fairly similar to pumping is a chest-fly; average values for machine chest flys (flies?) quoted on the 'net show that any male more advanced than "novice" can exert more force than their body weight.
And if you did manage to exert more force on a floor pump than your body weight you'd be (briefly) doing a different kind of flying.
Of course, in a way this is all academic. All you need is a smidgen more than the pressure in the tyre - did you *really* need to get them up to 195 psi?