VAM (bicycling)


VAM is the abbreviation for the Italian term velocità ascensionale media, translated in English to mean "average ascent speed" or "mean ascent velocity", but usually referred to as VAM. The term, which was coined by Italian physician and cycling coach Michele Ferrari, is the speed of elevation gain, usually stated in units of metres per hour.

Background

VAM is a parameter used in cycling as a measure of fitness and speed; it is useful for relatively objective comparisons of performances and estimating a rider's power output per kilogram of body mass, which is one of the most important qualities of a cyclist who competes in stage races and other mountainous events. Dr. Michele Ferrari also stated that VAM values exponentially rise up with every gradient increase. For example, a 1180 VAM of a 64 kg rider on a 5% gradient is equivalent to a VAM of 1400 m/h on a 10 % or a VAM of 1675 m/h on a 13% gradient. Ambient conditions have less effect on steeper slopes since speeds are lower on steeper slopes
The acronym VAM is not truly expanded in English, where many think the V stands in some way for vertical, and the M represents metres, for instance "Vertical Ascent Metres/Hour." Ferrari says,

I called this parameter Average Ascent Speed.

A direct translation of "velocità ascensionale media" is "mean ascent velocity" leading to an expansion of the acronym in English as Velocity, Ascent, Mean.

Definition

VAM is calculated the following way:
A standard unit term with the same meaning is Vm/h, vertical metres per hour; the two are used interchangeably.
The relationship between VAM and relative power output is expressed as follows:
This gradient factor ranges between 2.6 for a gradient of 6% and 3.1 for a gradient of 11%. To work out the gradient factor take 2 +

Examples

Examples:

1800+ Vm/h: Chris Froome.


1650-1800 Vm/h: Top 10 / Tour de France GC or mountain stage winner.


1450-1650 Vm/h: Top 20 / Tour de France GC; top 20 on tough mountain stage.


1300-1450 Vm/h: Finishing Tour de France mountain stages in peloton


1100-1300 Vm/h: The Autobus Crew

Other examples of its usage can be found at CyclingNews.com.