Alaina Randerson
Garrett Maclachlan
Katie Roley
5/29/11
Submaximal Lab Report
Purpose
Sub-maximal exercise testing is a useful test in estimating an individual’s aerobic power
when maximal exercise testing is not practical. Based on a subject’s age and body
mass, sub-maximal tests apply the connection of oxygen consumption, workload, and
heart rate to gather information about aerobic capacity and therefore identify the fitness
level of the subject. This form of exercise testing is often used to monitor the progress of
an individual in a training program. Sub-maximal testing is also a successful alternative
to maximal testing when the subject has injuries or other health issues preventing them
from being able to safely complete a maximal exercise test.
Methods
The subjects resting heart rate and blood pressure was taken before any exercise
began. Then, the subject pedaled at an intensity of 0.5 kp for three minutes at a
cadence of 50 bpm. The heart rate was taken for 15 seconds each minute for three
minutes. The subject’s blood pressure was taken at the end of the third minute.
Depending on the heart rate at the end of the first stage, the subjects next intensity was
determined. Once the workload column was determined, the subject was to stay in that
column and increase the intensity depending on the designated column every three
minutes. Again, heart rate was taken for 15 seconds every minute and the blood
pressure was taken at the end of every third minute, thus twelve heart rates and four
blood pressures were recorded for all four workloads. After the test was complete, all
intensity was taken off and heart rate and blood pressure were immediately recorded
post exercise.
Results
Garrett is a 22 year old, active male. His lowest heart rate of 95 bpm, was at the first
workload of 0.5 kp. The highest heart rate was 130 bpm and was recorded at the 4th
workload of 2.5 kp. He has an estimated maximum heart rate of 198 bpm based on the
equation: HR max= 220-age. His predicted maximum O2 uptake is 4.4 L/m which also
equals 62.86 ml/kg/min.
Resting
(bpm)
0.5 (kp)
1.5
(kp)
2.0
(kp)
2.5
(kp)
HR 1
95
97
118
122
HR 2
98
106
121
128
HR 3
101
109
120
130
Final
(bpm)
Resting
(bpm)
0.5 (kp)
1.5
(kp)
2.0
(kp)
2.5
(kp)
95
Final
(bpm)
97
Table 1: Heart Rates and Corresponding Workload for Garrett Maclachlan
Heart Rate (bpm)
Estimated VO2 max
(ml/kg/min)
Predicted Heart Rate
62.86
-10
57.14
+10
68.57
Table 2: Estimated VO2 max Depending on Heart Rate, Increasing and Decreasing for
Garrett Maclachlan
Alaina is a 21 year old, active female. Her lowest heart rate was 87 bpm at a workload
of 0.5 kp. Her highest heart rate was 155 bpm at a workload of 2.0 kp. She has an
estimated maximum heart rate of 199 bpm. Her predicted max O2 uptake was 3.0 L/min
which also equals 42.37 mL/kg/min.
Resting
(bpm)
0.5 (kp)
1.0
(kp)
1.5
(kp)
2.0
(kp)
HR 1
103
119
141
138
HR 2
101
120
146
148
HR 3
116
119
136
155
87
113
Table 3: Heart Rates and Corresponding Workload for Alaina Randerson
Heart Rate (bpm)
Final
(bpm)
Estimated VO2 max
(ml/kg/min)
Predicted Heart Rate
42.37
-10
36.72
+10
47.32
Table 4: Estimated VO2 max Depending on Heart Rate, Increasing and Decreasing for
Alaina Randerson
Katie is a 21 year old, active female. Her lowest heart rate was 92 bpm at a workload of
0.5 kp. Her highest heart rate was 160 bpm at a work load of 2.0 kp. She has an
estimated heart rate of 199 bpm. Her predicted maximum O2 uptake was 2.1 L/min
which equals 35.89 mL/kg/min.
Resting
(bpm)
0.5 (kp)
1.0
(kp)
1.5
(kp)
2.0
(kp)
HR 1
97
104
130
149
HR 2
98
113
135
158
HR 3
103
114
140
160
92
Final
(bpm)
139
Table 5: Heart Rates and Corresponding Workload for Katie Roley
Heart Rate (bpm)
Estimated VO2 max
(ml/kg/min)
Predicted Heart Rate
35.89
-10
33.33
+10
38.46
Table 6: Estimated VO2 max Depending on Heart Rate, Increasing and Decreasing for
Katie Roley
Conclusion
Garrett’s predicted maximum O2 output and maximum heart rate were 62.86 mL/kg/min
and 130 bpm, respectively. Alaina’s predicted maximum O2 output and maximum heart
rate were 42.37 mL/kg/min and 155 bpm, respectively. Katie’s predictect maximum O2
output and maximum heart rate were 35.89 mL/kg/min and 160 bpm. This shows that all
subjects were successful at completing the Submaximal Test without reaching too high
of a heart rate. This is important in a clinical setting to allow researchers to determine an
individual’s max O2 output without causing too much stress on their cardiovascular
system. This would be useful for subjects with obesity, cardiovascular disease, or high
blood pressure.
Garrett’s maximum O2 output was predicted from his maximum heart rate. This was
then used to make a rough estimate of his maximum O2 output had his heart rate been
10 bpm lower and 10 bpm higher than his predicted heart rate. The values, 57.14
mL/kg/min and 68.57 mL/kg/min, respectively, are not as accurate as they would be if
the test manipulated his heart rate accordingly. These are good indicators of the general
parameters his maximum O2 output would be if an actual maximal test was performed.
Alaina noted that as the experiment continued and the intensity increased, her muscles
began to fatigue more and had a slight “burning” sensation. The “burning” sensations is
most likely due to the build of of free H+ ions in her skeletal muscle. We also noted, that
her heart rate had a tendency to drop slightly each time after the intensity was
established. This is probably due to the buffering of H+ ions out of the muscle through
the production of lactate, thus her heart did not have to work as hard to maintain the
same pace. The drop in heart rate may also be due to the “acclimation” to the workload
that was presented.
Katie had the highest heart rate out of all the subjects with a lower estimated maximum
O2 output. Compared against Alaina’s data, Katie has a lower endurance capacity and
would reach fatigue faster. Garrett was capable of completing this test with the least
amount of effort, showing that he has the highest endurance capacity out of all the
subjects. These assumptions are to be expected based on the differences in body
mass, gender, age, and the types of training between the subjects. It has been proven
that exercise stress inhibits leptin, which is a hormone that affects dietary intake of
carbohydrates . With this decrease in leptin, subjects with higher O2 uptake levels
would use carbohydrates more as a fuel then subjects with low O2 uptake levels (Hilton
and Loucks 2000).
Even though this experiment helps to predict individual’s maximum O2 output, there are
a few possible errors in the test. The test assumes that maximum O2 output is
dependent the subject’s heart rate which is not actually calculated or tested, but simply
assumed by a simple and over generalized calculation of maximum heart rate=220-age.
The test also assumes that the mechanical efficiency is the same for all subjects, thus
making the test more generic and less specific for each individual. Also, if the ergometer
was not calibrated correctly, all of the results would be inaccurate.
The Submaximal Test could be made more accurate to estimate an individual’s
maximum O2 output by changing the workload values for females and males, thus
accounting for the mechanical efficiencies for individual’s. Because female muscles are
different in maximal contraction than male’s, equations from different Submaximal Tests
can be used to calculate the appropriate workloads for different genders. By changing
the workloads, the maximum O2 output can be estimated graphically more accurately
since the intensity would be more precise for the individual.
References
Hilton, L.K., and A.B. Loucks. "Low Energy Availability, Not Exercise Stress,
Suppresses the Diurnal Rhythm of Leptin in Healthy Young Women." Am. J. Physiol.
Endocrinol. Metab., 2000: E43-E49.