Originally Posted by
spelger
well, the reason why i see it as useless is because of the wide open interpretation, at least that is how i read the thread opener. the units are meters per hour. i can always ride a steep short hill and use maximum power. compare that with an equally steep but much longer hill i highly doubt my mph will be the same. my local favorite is about 8 miles long.
Similar to power/weight VAM will vary with duration. It's typically used to measure ascent on longer climbs. It's a good metric to compare your performance with others on similar climbs as well as your own performance over time on similar climbs.