I remember that in my childhood I read advertisements by Charles Atlas, a strong man, who promised to build my muscles as big as his. It was done by "dynamic tension." You simply pitted one muscle against another, let's say one fist against another fist, pressing as hard as you could. Soon you would have muscles. So I decided I would do a funny play on this. I would attempt to accomplish nothing with the Atlas method. The idea would be to open a door while trying to keep it closed, and to close a door while trying to keep it open. There were two doors in my living room, one to the outside, and one to the garage. For one half-hour, I pushed open the outside door as slowly as could with one hand, while with the other hand I pulled it back almost as much. I used a lot of effort, tensing my arms and body trying to keep the door moving outward as if it was the minute hand of a clock. That way, the door was fully open when my egg-timer rang at the end of the half-hour. I saw that I was standing on the threshold exactly between inside and out.
With the other door, I went out into the garage to pull the living room door closed (since it opened inward). I began therefore, on the threshold exactly between in and out, and moved slowly outward as I drew it towards me. I pulled with my right hand while I pushed back with my left. Since I was facing the other way this time, and the door knob was reversed, I pulled and pushed with opposite hands.
During the first period when I began practicing my "dynamic tension," I began to sweat and then to shake. I thought this was quite humorous. When the egg-timer rang I was a little faint. In the second half-hour the shaking became pronounced and I wondered what was happening to me. At the end of the half-hour I barely heard the bell as I took my hands away from the closed door. They weren't my hands, they had no feeling in them. I was quite dizzy and couldn't keep my balance.
I kept on shaking and managed to get to my bed to lie down. Several hours passed before I could get up to walk safely. Later, a doctor told me I had nearly put myself into a convulsion because I hadn't breathed normally.