The document contains data tables and analysis of changes in vital signs (blood pressure, heart rate, etc.) in response to cold water immersion and exercise. Key findings include:
1) Cold water immersion caused increases in systolic/diastolic blood pressure, mean arterial pressure, and heart rate, preparing the body for "fight or flight."
2) Exercise similarly increased these vital signs. Cardiac output increased by 5,800 mL/min based on a stroke volume increase from 75 to 100 mL/beat and heart rate change.
3) Recovery heart rate returned to resting levels 20 seconds after reaching maximum, showing homeostasis mechanisms act more slowly than stress responses.
1. DATA
Table 1–Baseline Blood Pressure
Systolic pressure Diastolic pressure Mean arterial pressure
(mm Hg) (mm Hg) (mm Hg)
121 64 78
Table 2–Blood Pressure
Response to Cold
Systolic pressure Diastolic pressure Mean arterial pressure
(mm Hg) (mm Hg) (mm Hg)
137 68 83
Table 3
Condition Heart rate Time
(bpm) (s)
Resting heart rate 72.01
Maximum heart rate 80.32 60.07
Rebound heart rate 72.01 20 seconds
Data Analysis
1. Describe the trends that occurred in the systolic pressure, diastolic pressure, mean arterial
pressure, and heart rate with cold stimulus. How might these responses be useful in a “fight or
flight” situation?
When the cold stimulus was added the systolic pressure, diastolic pressure, mean arterial
pressure, and heart rate went up. In addition to the emotional discomfort we feel when faced with
a stressful situation or introduced to an uncomfortable stimulus, our bodies react by releasing
stress hormones (adrenaline and cortisol) into the blood. These hormones prepare the body for
the "fight or flight response" by increasing the heart rate and blood pressure.
2. 2. As a vital sign, blood pressure is an indicator of general health. A high blood pressure
(140/90 or higher) increases the risk of cardiovascular disease and strokes. Collect the systolic
and diastolic pressures for the class and calculate the average for each. Rate the class average
blood pressure using the follow scale:
Blood Pressure Category
140/90 or higher High
120–139/80–89 Pre-hypertension
119/79 or below Normal
114/69 - on average our class’s blood pressure is normal
3. How long after immersion did your heart rate reach its maximum value? Explain the
physiologic mechanism that led to this change in heart rate.
After about 20 seconds of submerging her foot into the ice water, Anna Lee’s heart rate reached
its maximum value of 80.32 bpm. The physiologic mechanism that led to this change in heart
rate was when her foot was submerged into the water there was decrease circulation to her foot,
which caused stress.
4. Describe the changes in heart rate that occurred after the maximum value. How can you
explain the minimum heart rate value? How would you explain the heart rate variations seen in
the remainder of the experiment?
After Anna Lee’s foot was submerged into the ice water her heart rate reached its maximum at
20 seconds. Her heart rate when resting, before submerging her foot, was 72.01 bpm. This
would explain why 20 seconds after reaching her maximum heart rate it returned to 72.01 bpm.
5. How long after the maximum heart rate did it take to arrive at your rebound heart rate? What
can you say about the relative speed of physiologic response to a stimulus vs. the speed of
mechanisms that are designed to maintain homeostasis?
After reaching the maximum heart rate was reached it took about 20 seconds to arrive at the
rebound heart rate. The speed of a physiologic response to a stimulus is the heart rate
increasing during exercise or stress. In this case it's the heart rates reaction to cold water. This
reaction is very quick compared to the speed of mechanisms returning the heart rate back to
normal which is slower.
6. If the heart rate is too slow there is inadequate blood pressure to maintain perfusion to the
3. brain. This can lead to loss of consciousness (fainting). Keeping in mind the autonomic nervous
system responses that you observed in this experiment, explain the sequence of events that
results in a severely frightened person fainting.
When becoming frightened your autonomic nervous system will stimulate your blood vessels to
dilate or expand to get more blood and oxygen flowing through the body. Because all the vessels
are dilating it can lower the blood pressure throughout the circulatory system. If the pressure is
low enough your brain will momentarily shut down and cause you to pass out.
DATA:
Table 1–Baseline Blood
Pressure
Systolic pressure Diastolic pressure Mean arterial pressure Pulse
(mm Hg) (mm Hg) (mm Hg) (bpm)
119 65 75 76
Table 2–Blood Pressure
After Exercise
Systolic pressure Diastolic pressure Mean arterial pressure Pulse
(mm Hg) (mm Hg) (mm Hg) (bpm)
137 73 94 115
Table 3–Heart Rate
Condition
Resting heart rate (bpm) 97.01
Maximum heart rate (bpm) 154.8
Recovery time (s) 35
DATA ANALYSIS
1. Describe the trends that occurred in the systolic pressure, diastolic pressure, mean arterial
4. pressure and pulse with exercise. Assume that the stroke volume increased from 75 mL/beat to
100 mL/beat. Use this information and the change in pulse with exercise to calculate the change
in cardiac output (stroke volume × heart rate) that occurred per minute.
-- The systolic pressure was higher than the diastolic pressure, mean arterial pressure,
and pulse. The diastolic pressure and mean arterial pressure was around the same numbers.
But the pulse became higher that it originally was on the baseline.
The change in cardiac output is 5,800.
2. Pulse pressure is the difference between systolic pressure (peak pressure during active
contraction of the ventricles) and diastolic pressure (the pressure that is maintained even while
the left ventricle is relaxing). Describe the change in pulse pressure seen with exercise. Which
component of the blood pressure is most responsible for this change?
- your pulse pressure rises during exercise because your heart rate increases and you begin to
breath harder. Cardiology is the component of the blood pressure that is the most responsible
for the change of someone’s pulse pressure with exercise.
3. A change in pulse pressure can be seen in a variety of medical conditions. What would you
expect to happen to the pulse pressure in the following examples?
(a) In atherosclerosis there is a hardening of the arterial walls.
- your pulse pressure widens.
(b) A damaged aortic valve does not seal properly and allows blood to flow back into the
ventricle during diastole.
- Pulse pressure begins to fall when there is aortic valve insufficiency.
4. Normal resting heart rates range from 55−100 beats per minute. What was your/the
subject’s resting heart rate? How much did your/the subject’s heart rate increase above resting
rate with exercise? What percent increase was this?
- The subjects resting heart rate was 76 bpm. The subjects heart rate increased by 39 bpm
with exercise. The heart rate increased by 51%.
5. How does your/the subject’s maximum heart rate compare with other students in your
group/class? Is this what you expected?
5. Other students heart rates were pretty close to our subjects heart rate. I expected them to
be about the same because all the subjects are the same age and were testing heart rate
under the same conditions.
6. Recovery time has been shown to correlate with degree of physical fitness. How does
your/the subject’s recovery rate compare to that of your classmates? Is this what you expected?
-Our subjects’ recovery rate was slightly shorter than other groups because our subject is a
softball player; therefor she is in better shape. This is the result that I expected because she
works out more often than the subject in other groups.
7. Congestive heart failure is a condition in which the strength of contraction with each beat
may be significantly reduced. For example, the ventricle may pump only half the usual volume of
blood with each beat. Would you expect a person with congestive heart failure to have a faster or
slower heart rate at rest? With exercise?
-I would expect someone with congestive heart failure to have a faster heart rate both at rest and
when exercising, because the muscle is not as powerful so the heart will have to pump more
quickly to compensate for the loss in pressure.
8. Medications are available which can slow the heart or speed it up. If a patient complains of
feeling poorly and has a heart rate of 120 beats per minute, should you administer a medicine to
slow the rate?
-Yes, you should attempt to slow the patients’ heart rate, because a normal heart rate should be
between 50 and 100 at rest and the patients heart rate is at 120.