Why does holding something up cost energy while no work is being done?

This is about how your muscles work — the’re an ensemble of small elements that, triggered by a signal from nerves, use chemical energy to go from less energetical long state to more energetical short one. Yet, this obviously is not permanent and there is spontaneous come back, that must be compensated by another trigger. This way there are numerous streches and releases that in sum gives small oscillations that create macroscopic work on the weight.

— This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.

— Physics Stack Exchange

— answered Dec 16 ’10 at 11:52

— mbq

2012.10.12 Friday ACHK