The Trance

I sit on my stationary bike for half an hour a day,
it is incredibly boring if I have nothing to occupy my mind.
Today there was a stream of thought I waded out but
found it full old junk – junk can also be new- so I built
a wall of numbers to keep the rivulet away.
I fell into a trance, or think I did; an hour had past
when I looked at the watch, an hour had gone a new record.
The pressure of the flowing thought broke the wall
and sceptical I was not sure if I had had my exercise or
been asleep on the bike?