Ward, S.A. and
Whipp, B.J., 2010. Kinetics of the ventilatory and metabolic responses to
moderate-intensity exercise in humans following prior exercise-induced
metabolic acidaemia. In New Frontiers in Respiratory Control (pp.
323-326). Springer, New York, NY.
Fusaroli, R., Tylén, K. and Jegindø, E.M., 2013. Using complexity metrics with
RR intervals and BPM heart rate measures. Frontiers in physiology, 4.
Seip, R., 2014.
Cardiovascular and Pulmonary. Essentials of Sports Nutrition and
Datta, D., Normandin, E. and ZuWallack,
R., 2015. Cardiopulmonary exercise testing in the assessment of exertional
dyspnea. Annals of thoracic medicine, 10(2), p.77.
Arena, R., Sietsema, K., Myers, J., Coke, L., Fletcher, G.F., Forman, D.,
Franklin, B., Guazzi, M., Gulati, M. and Keteyian, S.J., 2010. Clinician’s
guide to cardiopulmonary exercise testing in adults. Circulation, 122(2),
In this study, the minute ventilation
during maximal exercise was three times higher than value recorded at rest,
which is in line with the previous reports. Therefore, the method adopted in
the study was effective and produced results with a high level of accuracy. In addition,
most of the subjects had some reserve ventilation when the exercise was
stopped. Consequently, it can be argued that ventilation does not have a
limiting impact in exercise for normal people.
Nevertheless, several factors are also
likely to affect the outcomes in healthy individuals. For instance, differences
in age, sex, lean body mass, hemoglobin level, habitual level of physical
activity, and physical conditioning have a significant impact on the
physiologic variation in oxygen uptake (Ward and Whipp, 2010).
The uptake of oxygen depends on both the
cardiac output and the arteriovenous oxygen differences flow (Balady, et al.,
2010). When a person is taking an exercise, the muscles involved require more
energy and blood flow. When oxygen uptake increases from rest in response to an
increased level of muscle exercise, the cardiac output normally increases by
about 4.3 times while the artriovenous oxygen differences increases by about
2.2 times. Consequently, the ability to increase the cardiac output in a normal
person is the principal factor that determines the maximal oxygen uptake.
Cardiac output is the product of the stroke volume and the rate of heart. When
taking an exercise, the body’s stroke volume increases significantly until the
rate of the heart is about 120-130 bpm (Datta, Normandin, and ZuWallack, 2015).
After this level is reached, the heart rate becomes the principal factor that
determines the cardiac output.
The experiment results provide evidence
that the body takes more oxygen and removes more carbon dioxide when it is
involved in exercises than when it is at rest. At the same time, the body’s
heart rate increases significantly when a person is taking exercise than when
at rest. These changes were significantly large and provide evidence that there
are marked physiological changes when a person is taking exercise (Wallot, et
al., 2013). Previous studies in physiology provide evidence that these changes
are attributed to the need for more energy in the body muscles to enable one to
take the exercise.
From figures 1, 2, 3, and 4, it can be
seen that the values for all the variables were comparable because different
results were obtained when the subjects were resting and when they were
involved in the bicycle exercise. Specifically, it can be seen that the heart
rate increased from an average of 71 bpm to about 107 bpm for the entire group.
Therefore, there was a mean increase of about 36 bph, which is equal to 50.7%. Similarly,
ventilation increased from an average of 0.4 to about 1.6 when the individuals
were taking the exercise, which is about 1.2 increase rate or 300%. The minimal
standard deviations show that the values taken for each individual were roughly
close to the mean, which proves that the measuring methods had a high level of
accuracy flow (Balady, et al., 2010).
Figure 4. Bar graph comparing the values
of carbon dioxide rate for 8 individuals taken when at rest and during exercise
Figure 3. Bar graph comparing the values
of heart rate average for 8 individuals taken when at rest and during exercise
The group averages were then determined
and compared for all the variables as shown in figures 3 and 4
Figure 2. Bar graph comparing the values
for an individual taken when at rest and during exercise
As shown in the graph under figure 2, the
variables taken when at rest and during exercise were compared for the
individual. The table shows that during exercise, all the variables were higher
than when at rest
Figure 1. Table of values for an
individual taken when at rest and when doing exercise
Average heart rate in bpm
Minute ventilation in L/min
Fraction of oxygen in air taken
Fraction of carbon dioxide in air
taken in (%)
The values for an individual’s measures of
heart rate, oxygen intake, carbon dioxide output, and ventilation were recorded
as shown in the table in figure 1.
A mouthpiece and a Y-valve were used on
the subject noses to collect the gas exhaled. With this method, the minute
ventilation, oxygen consumed, and carbon dioxide output were measured using an
oxyscreen and pneumotachograph. The results were recorded after every 30
seconds. Also, during the exercise for each subject, an electrocardiogram was
used to measure heart rate and was monitored continuously on the oscilloscope
and the values were recorded every 30 minutes. Blood pressure was also measured
every minute when the workload was increased for all the subjects. Finally, an
aerobic threshold was identified and recognized as the oxygen uptake when it
was clear that the ratio of minute ventilation to carbon dioxide output was no
First, the values of heart rate and gas
component (oxygen and carbon dioxide) inhaled and exhaled were taken several
times for each subject when at rest. Then, each subject was given a chance to
ride on a bicycle ergometer after one hour of fasting. The exercise method
involved 1 minute of pedaling on a load-free bicycle at about 50 revolutions
before the load was increased by 25 watts each minute until each subject
reached exhaustion point.
A quantitative study design was adopted in
which 8 students falling within the same age group (18-24) in the physiology
class were used as the study sample. All the students were clinically healthy
and were not using drugs that might have affected their pulmonary physiological
processes. In addition, the ECG and pulmonary function test for all the
subjects were within the normal limits when the test was carried out. Moreover,
not of the student was an athlete.
The purpose of this experiment was to make
comparisons between the values of heart rate and ventilation rate when a group
of people is as rest and when they are involved in vigorous exercises.
An analysis of the measured inhaled and
exhaled gases as well as the heart rates enables physiologists to make accurate
quantifications of the oxygen consumed and the carbon dioxide generated from
the body during exercise (Seip, 2014). In addition, it enables one to compare
the uptake oxygen and generation of carbon dioxide between the time the body is
at rest and when it is involved in exercise. These values are significant in
medicine because they are involved in diagnosis of such conditions as dyspnea
and other lung diseases.
Physiologically, there is a marked
difference in the human body processes between when at rest and when the
individual is involved in vigorous exercise. During exercise, the muscles
involved require more energy and blood flow (Balady, et al., 2010). As a
result, the more oxygen is inhaled into the lungs. From here, the increased
amount of oxygen is transported to the heart by pulmonary vessels and then
delivered to the active muscles by the arterial circulatory system.
Consequently, more blood is pumped towards these muscles, which requires an
increased hart rate. At the same time, the muscles involved in exercise produce
more carbon dioxide when their cells are making energy flow (Balady, et al.,
2010). The carbon dioxide is transported to the lungs for exhalation out of the
body. Therefore, more non-oxygenated blood leaves the muscles back to the lungs
during exercise than at rest.