Write a short story about a time when you had to overcome the force of gravity to get something done

I was cleaning my office last week, getting ready for the arrival
of my daughter and four grandchildren from out of the country. 
I wanted them to be able to walk into my office if they wanted to.

I got a big empty box, and started filling it up.  I picked up a bunch
of stuff from the floor, then more from the counter-tops, and put it all
into the box.  I stopped when the box was full to the top, and I put the
cover on the box.

I wanted the box to be on the top shelf in the closet, but gravity
was holding it to the floor ?  What could I do ? ! ?

I had an idea:  I went to the kitchen and got a can of spinach. 
I squeezed it with one hand until the can popped open and the
spinach all shot out.  As the spinach reached the top of its arc
and started falling, I got under it, caught it all in my mouth, and
swallowed it in one gulp. 

That was exactly what I needed.  While I blew a train-whistle through
my pipe, huge bulges instantly popped out of my arms and legs, and
I went back to the office in one jump.

I picked up the heavy box from the floor with one hand, almost as if
it was a feather or a piece of tissue, and I tossed it up to the top shelf
in the closet.

My big spinach muscles overcame the force of gravity, and I was able
to get the lifting job done.