True Fitness Z9 Treadmill User Manual


 
Z 8 a n d Z 9 S e r i e s Tr e a d m i l l O w n e r ' s G u i d e
24
BasIc operatIon
Calorie Expenditure Calculations
three : BasIC operatIon
True treadmills use the calorie expenditure formula as described in
Guidelines for Exercise Testing and Prescription from the American
College of Sports Medicine. This is the most widely
accepted formula for running and walking.
The ACSM guide says that running burns calories
twice as fast as walking, e.g., a 150-pound person
jogging at 5 mph requires 548 calories per hour, while
walking at 5 mph requires 274 per hour. See Appendix
C for more details.
(Other respected researchers such as David Costill think the ACSM
overstates the energy difference between running and walking.
Costill believes running requires 60% more energy than walking, not
100% as calculated by the ACSM. Using the same example, Costill's
calculations result in 496 cal/hour for running 5 mph, with 313 cal/
hour for walking 5 mph.)
One potential source of calorie estimate
error is that the treadmill doesn't know
if you are running or walking, so it has
to make some assumptions. It assumes
you are walking at 3 mph and slower,
and running at 5 mph and faster. Between those two speeds, the
treadmill combines the walking and running formulas to make its
best guess.
Variations in human exercise efficiency are another potential source
of error, with differences of plus or minus 10% common in the
population
a note
a
Bout
c
alorIe
e
xpendIture
c
alculatIons