CS8.0 Bikes Owner’s Guide
85
Appendix C
Constant torque is used in a modified way in Bike Mode. In
addition to constant resistance for a given “gear,” additional
torque is applied to simulate wind and road resistance, as well
as to compensate for different body weights.
Personal Power was initially designed to vary workload at a
1:1 ratio with body weight, just like a METs-based exercise
prescription. However, it turns out that human endurance and
power generating capability varies with the 2/3 root of body
weight, not straight body weight. This relationship can be seen
in everything from weightlifting world records to distance
running competitions. (See McMahon and Bonner, On Size
and Life (1985), page 55).
Since METs do not work the way they’re supposed to, Personal
Power is based on a new unit of measure that correctly
accounts for body weight. This new unit of metabolic measure,
called the T-MET, is defined as:
T-MET = watts / (kg) 2/3
where watts is power applied to an external machine from the
exerciser, and kg is the exerciser’s body weight in kilograms.
The
Personal
Power
Calculation
