Some people who use treadmills at home are familiar
with this scenario: they turn the machine on and everything seems to work; then
minutes into their session, the machine stops.
Treadmills may not compare with a
jog outdoors, but you wouldn't want to run laps when it's hot as a skillet
outside. Unfortunately, treadmills can wear down to the point that the belt
fails or the motor goes kaput. Most treadmills remain unused for years due to a
single, replaceable broken part.