Well :  weight = mass * acceleration so you are measuring a change in weight as your (constant ) mass is oscillating thus acceleration is varying.

MikeW

>>> mwillis@FOXINTERNET.NET 05/15/00 07:33AM >>>
To be picky a little here - I'd think your weight doesn't change there.
Your body probably moves a little though, in response to the pressure
change when your heart beats - and that's what they measure;  your
inertia's effected by the pulse, and oscillates <G>  Interesting info!

Same effect as if you drop a hammer in an airplane - You can NOT use the
oscillation of measured weight as an antigravity drive AFAIK, you CAN
measure the change to tell that the hammer's been dropped, though...

  Mark