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3. Have you developed chest pain within the past month?
4. Do you tend to lose consciousness or fall over as a result of dizziness?
5. Do you have a bone or joint problem that could be aggravated by the proposed physical activity?
6. Has a doctor ever recommended medication for your blood pressure or a heart condition?
7. Are you aware, through your own experience or a doctor’s advice, of any other physical reason
against your exercising without medical supervision?
Nautilus
®
Sub-maximal Fit Test
The Nautilus
®
Fit Test is a program that estimates maximal aerobic capacity based on heart-rate
response to sub-maximal exercise.
The Nautilus branching protocol is a series of 3-minute stages of continuous exercise at increasing
intensity. The first stage is a warm-up at approximately 4 METs. The intensity of the remaining stages
is based on the heart rate response to the warm-up. The test is designed to raise the steady state heart
rate of the subject to at least 115 beats/minute. It is important to remember that two consecutive heart
rate measurements must be obtained above 115 beats/minute to predict VO2max. The test typically
lasts from 6 to 15 minutes. The test will terminate if the heart rate does not continue to rise from state
to stage.
In the Nautilus
®
protocol, each work rate is performed for 3 minutes, with heart rates recorded during
the final 4 seconds of the second and third minutes of each stage. If the heart rates are within 5
beats/min, then the heart rate during the last minute is plotted against the work rate, and the program
advances to the next 3-minute stage. The program continues for two to four stages until two steady
state heart rates above 115 beats/min are obtained in two consecutive stages. The line generated from
the plotted points is then extended to the age-predicted maximal heart rate. A corresponding maximal
work rate and VO2max can then be calculated.
At the end of the 3rd minute of each stage, if the heart rates at the end of the 2nd and 3rd minute are
not within 5 beats/min of each other, then that work rate is maintained for an additional minute. At the
end of the 4th minute, the heart rate is compared to the heart rate at the end of the 3rd minute. If the
heart rates are within 5 beats/min, then the heart rate during the 4th minute is plotted against the work
rate. If the heart rate at the end of the 3rd and 4th minute are not within 5 beats/min, then the work rate
is maintained for one more additional minute. If the heart rate at the end of the 4th and 5th minutes are
within 5 beats/min, then the heart rate at the end of the 5th minute is plotted against the work rate. If
the heart rate at the end of the 4th and 5th minutes are not within 5 beats/min, then the test failed.
Once two consecutive heart rate measurements are obtained above 115 beats/min range, then the test
ends successfully and the results are displayed. Estimated maximum aerobic capacity is shown in ml/
kg/min and METs. Next, the results are compared to normative values for others of the same age range
and gender.
THE NAUTILUS
®
FIT TEST PROGRAM