Owner's Guide Treadmill Excel Series
E X C E L  S E R I E S  O W N E R ’ S  G U I D E
Gerkin Fitness Test
CHAPTER FOUR: GERKIN FITNESS TEST 
One way to measure your overall fitness is to take a Gerkin fitness 
test. Named after the Arizona researcher who designed this test, 
this submaximal treadmill test (submaximal means you work below 
maximum effort) is used to predict VO2 max: the volume of oxygen 
you can consume while exercising at your maximum capacity. This 
particular test has gained great popularity in the firefighter and law 
enforcement community. Like most fitness tests, it is classified as 
a graded exercise test (GXT). The test is stopped at the point your 
heart rate reaches 85% of your age-predicted maximum. 
Select the Gerkin test under the Advanced Options key. Enter your 
age, which is used to calculate your test termination point.
The Gerkin protocol starts 
at 4.5 miles per hour at a 
0% incline. It then increases 
speed or incline every 60 
seconds. For example, at the 
seven-minute mark, the speed 
increases to 6 miles per hour 
while the incline raises to 8%.
When your heart rate reaches 
85% of your age-predicted 
maximum, the test waits for 
your heart rate to exceed the 
target for 15 seconds, then 
terminates the test.
Using the 
Gerkin Test
The version of the Gerkin 
Protocol that True Fitness 
uses in its exercise machines 
is the new equation of 
205.8 – 0.685*age. To better 
understand why we selected 
this method over the outdated 
“220 – age” maximal heart 
rate equation, you can review 
the scientific paper in Journal 
of Exercise Physiology, a PDF 
document located at http://
www.asep.org/Documents/
Robergs2.pd
f.
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