A walking human will exert more than double his standing pressure
Weight is equal to mass times gravity (W=mg) but weight is a force, so (W=Fweight=mg). So when you stand your total force is just mass times gravity. But when you walk you are generating a downward acceleration when you step, you are 'pushing ' down with your leg (this is more obvious when you run). So not only is there a force down from standing but an additional force due to the rate of change of the downward momentum of you leg. So momentum is equal to mass times velocity (p=mv), but your momentum is constantly changing with respect to time so (dp/dt=mdv/dt + vdm/dt, where dv/dt is equal to a). Now since we know your changing momentum is causing a force we may say that F=dp/dt. Now lets put all this back together! Ftotal= Fwieght + Fmomentum then
Ftotal= mg + ma! And that is why walking causes more pressure on the earth than standing