The tool begins to fail,

to turn against its user. The treadmill 
fails to warn you of its desire to speed up. 
Because it does, in one spectacular burst. 
Perhaps there's a race it always wanted to win, 
a record to break? It's now or never. You 
were merely practice. You try to hang on 
to the bars, but a great wind sweeps you off 
the rolling hills that only minutes ago 
you were climbing so earnestly—one foot 
after the other, your timer a modest promise 
that all trials are temporary and come to an end.