Biology 105 – Human Biology
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Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
Student ID#:
Student Name: Baybe Yormy Fireworks
Team Name:
Lab Assignment #: 4
Lab Title: Personal Life Metrics Muscle Fatigue
Date: 110301.1
Purpose / Objective(s):

Measure and correlate physiological life metrics including muscle fatigue with heart rate /
cardiovascular metrics.
Hypothesis (ese):

(1) There is a psychological connection between anticipated muscle fatigue and an increase in heart
rate.

My belief is that our brain sends signals to other parts of our bodies to prepare or ready for physical
exertion / muscle fatigue.

See attached and below http://www.heartmonitors.com/exercisetips/changing_heartrate.htm

(2) There is a correlation between heart rate and temperature.

My belief is that heart rate and temperature both increase as increased energy is exerted. Sweating is
way to help regulate or cool the body.

See below http://www.madsci.org/posts/archives/2001-06/991966089.Me.r.html
Materials / Subjects / Specimens;

Two humans were observed (one male, one female).

A scale was used to measure 3 standard free weights (7lbs/3kg, 22lbs/10kg, 28lbs/13kg)
Methods / Tools / Instrumentation / Procedures;

A Standard home set of free weights and personal digital watch/iphone were used to make all
measurements.

The procedure involved measuring resting heart rate, pre stress heart rate, peak heart rate after
physical exertion, heart rate 1 minute post peak and 5 minutes post peak.

To achieve peak heart rate 3 different standard free weights were used. Above measurements were
taken using each weight (7lbs/3kg, 22lbs/10kg, 28lbs/13kg).

In between each cycle there was a varied waiting period to achieve a resting or pre stress heart rate.
Results

Figure #1 shows the correlation between resting heart rate and pre stress heart rate. Key observation
is that resting heart rate is fairly constant compared to pre stress heart rate. Anticipation does seem
to play a role. The below article supports this observation:
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533565155
Biology 105 – Human Biology

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Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
Worth noting from Figure #2 is that it suggests that an individual in better shape/condition does not
have as much variance in heart rate when exposed to physical exertion. Possible a more efficient
system.
Analysis / Discussion:

Regarding my second hypothesis, while we did not measure body temperature as a variant during
this lab. I did become quite warm after reaching peak resulting in me removing my sweater. I also
observed that others in the room were doing the same. The below communication from M.Salik
Jahania, M.D., Surgery, Cardiothoracic, University of Kentucky supports this observation:
“The influence that the temperature of the body has on pulse rate is to increase it. There is no
direct relation but there is an indirect relation.”

It is possible that the heat level in the room also played a factor. We were in an enclosed space with
each student exerting energy possibly raising the temperature in the room. As stated below heart rate
can be affected by heat.
Environment Stresses: http://www.heartmonitors.com/exercisetips/changing_heartrate.htm
Heart rate is affected by external stresses on the body such as heat, humidity, cold, wind,
and altitude and air quality. With each stress, the human heart is affected and different
compensatory changes occur, one of those being adjustment in the beat of the heart.
Triathletes racing at the Hawaiian Ironman face most of these conditions simultaneously while
racing in one of the most strenuous events in the world. As a result, a heart rate monitor can help
provide them with key information on how their body is responding to the conditions and the
duration of this high intensity racing throughout the event.

The results that we observed in addition to the referenced documents do support my hypothesis.

Results demonstrate that there are a lot of variables that affect heart rate: extrinsic, environmental
and overall health and fitness levels.

Our bodies are very intuitive with regulating heart rate, with built in mechanisms like perspiring to
control body temperature.
Figure #1 shows resting heart rate versus pre stress heart rate. Key observation is that resting heart rate
is more constant while pre stress heart rate indicates more variance.
Average Heart Rate for Self vs Partner
ME
PARTNER
58
Ht Rate Post Stress
5 Minutes
64
Time Points
61
Ht Rate Post Stress
1 Minute
80
67
Ht Rate at Peak
89
59
Ht Rate Pre Stress
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533565155
Biology 105 – Human Biology
Session:
Section:
Class Location:
Days / Time:
Instructor:
Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
Figure #2: shows heart rates for me vs. my partner for the various time points. Key observation is that my
partner’s heart rate did not show as much variance (better shape).
Resting HR
Pre Stress HR
66
64
62
60
58
56
54
52
50
1
2
Pre Stress HR
3
4
Resting HR
5
6
Conclusions / Further Considerations:

It would be interesting to actually measure body temperature with the physical exertion / muscle
fatigue to better understand the correlation. I believe there is a mathematical equation to support this.

Heart rate can be affected by a lot of variables. It is important to educate your self on what a normal
heart rate is and to understand what variances from that normal range might signify.
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533565155
Biology 105 – Human Biology
Session:
Section:
Class Location:
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Instructor:
Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
ATTACHMENTS
Summary / Formal / Conclusive Results / Tables, Charts
Figure #3: Lab Data Observed and Collected
Weight
Kg
Reps for 1 Weight /
Ht Rate
Ht Rate
Ht
Ht Rate Pre Ht Rate
Minute or Stress
Post Stress Post Stress
Resting
Stress
at Peak
Fatigue
Level
1 Minute
5 Minutes
SELF (FEMALE)
3
37
Low
60
66
80
78
65
10
19
Medium
60
60
98
83
66
13
12
High
60
65
88
80
60
Avg.
60
64
89
80
64
PARTNER (MALE)
3
60
Low
62
56
60
62
58
10
48
Medium
62
62
72
61
56
13
18
High
Avg.
62
62
58
59
68
67
61
61
61
58
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533565155
Biology 105 – Human Biology
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Section:
Class Location:
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Instructor:
Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
Additional Notes / Research
Neural and Hormonal Affects There are two different factors involved in heart rate management:
intrinsic and extrinsic controls. Intrinsic regulation of heart rate is the result of the unique nature of
cardiac tissue – it is self-regulating and maintains it’s own rhythm without direction. Extrinsic controls
are those that come from both hormonal responses as well as the commands from the nervous
system: the central nervous system and the autonomic nervous system. Extrinsic regulation can
cause the heart rate to change rapidly because of chemicals that circular in the blood or by direct
action of nerves that go to the heart. A good example of this is to measure heart rate changes when
certain words or emotions are said or felt without a muscle contracting. Say the words, "we are going to
have a surprise test today" and watch heart rate extrinsically increase. Put on a heart rate monitor and
sitting completely still watch a movie and watch heart rate jump during a car chase or action thriller. There
is no cardiovascular or cardio respiratory change as a result of this change in heart rate; it’s simply the
affect on the heart of chemicals and nerves responding to an external experience.
http://www.heartmonitors.com/exercisetips/changing_heartrate.htm
WAYS TO CHANGE YOUR HEART RATE
There are a number of different factors that affect the control and response of heart rate. But, what controls the beat of the heart?
Neural and Hormonal Affects
There are two different factors involved in heart rate management: intrinsic and extrinsic controls. Intrinsic regulation of heart rate is the result of the
unique nature of cardiac tissue – it is self-regulating and maintains it’s own rhythm without direction. Extrinsic controls are those that come from both
hormonal responses as well as the commands from the nervous system: the central nervous system and the autonomic nervous system. Extrinsic
regulation can cause the heart rate to change rapidly because of chemicals that circular in the blood or by direct action of nerves that go to the heart.
A good example of this is to measure heart rate changes when certain words or emotions are said or felt without a muscle contracting. Say the words, "we
are going to have a surprise test today" and watch heart rate extrinsically increase. Put on a heart rate monitor and sitting completely still watch a movie
and watch heart rate jump during a car chase or action thriller. There is no cardiovascular or cardio respiratory change as a result of this change in heart
rate; it’s simply the affect on the heart of chemicals and nerves responding to an external experience.
The cardiovascular control center for the body is located in the ventro-lateral medulla. Here heart rate slows if activated by the cardio inhibitory center in
the medulla or speeds up if activated by the cardio accelerator.
From this site, the two channels of the autonomic nervous system originate the sympathetic and parasympathetic components. The sympathetic
components increase heart rate by releasing the neural hormone catecholamines - epinephrine and norepinephrine. These hormones are cardio
accelerators. Acceleration of the heart rate is called tachycardia.
The parasympathetic nervous system located in the brain stem and upper or sacral portion of the spinal cord slows heart rate. The parasympathetic
components decrease heart rate. These neurons release the neurohormone acetylcholine, which inhibits heart rate. The slowing of heart rate is called
bradycardia.
The combination of the neural and chemical components regulates heart rate and other heart functions. When you begin to exercise in heart zones 1-3,
heart rate increases because parasympathetic (cardioinhibitory) stimulation stops. During more strenuous exercise, heart zones 3-5, the heart rate
increase occurs by direct activation of the sympathetic cardioaccelerator nerves.
Exercise excites the relationship between the sympathetic accelerators and the parasympathetic depressor neurons. This change in the balance in their
activity called tonic activity leads to more involvement of the vagus nerves. The vagus nerves carry about 80% of the parasympathetic fibers, those
responsible for slowing heart rate. With increased vagal dominance, heart rate values change and slow. One of the training effects is the slowing of resting
and ambient heart rates. This is the result of the effect of fitness on the tonic activity and the favoring of greater activity by the vagus nerves to slow heart
rate. These adaptations following zone 1-3 or aerobic training occur to those who are sedentary and begin and exercise program as well as those who
maintain one. This is one of the benefits of training, a significant resting bradycardia.
The central nervous system plays the greatest role in control over heart rate during exercise. When you start a movement pattern, the central nervous
system sends impulses through the cardiovascular center in the medulla. There is a coordinated and quick response of both the heart and the blood
vessels to change blood pressure, tissue perfusion to respond to the requirements.
Page 5 of 6
533565155
Biology 105 – Human Biology
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Spring 2011
55244 4 Units
UVC1 St. Helena
F 9:00 AM – 3:50 PM
RIDDELL
http://www.madsci.org/posts/archives/2001-06/991966089.Me.r.html
Date: Wed Jun 6 21:29:15 2001
Posted By: M. Salik Jahania, M.D., Suregry, Cardiothoracic, University of Kentucky
Area of science: Medicine
ID: 985842739.Me
Message:
The influence that the temperature of the body has on pulse rate is to
increase it. There is no direct relation but there is an
indirect relation.
When body temperature is higher for reasons of infection or fever from any
inflammatory cause, the body also secretes catecholamines to increase
pulse rate. The result is to increase blood circulation throughout the
body. This allows more blood supply to the skin vessels where the
excess heat can be dissipated by the body by the phenomenon of conduction
and convection.
The thalamus in the brain has a thermostat that tries to regulate body
temperature at the normal body temperature. When the body temperature is
higher because of an increase in room temperature or in summer, the
body tries to cool off by opening small vessels in the skin to an
increased size to allow more blood flow to skin. This is helped by the
higher heart rate, since blood flow every minute = stroke volume per beat
* pulse rate.
But when there is infection in the body the thalamus itself is influenced
by the production of certain factors by the body's defence cells that
increase the thermostat setting to make the body generate higher
temperature. This is done by inducing shivering as ssen in fever and
chills. By shivering the muscles contract rapidly and generate excess
heat. This helps the body geneate more heat.
These factors also directly influence heart rate and increase it.
Therefore the relationship as you see between body temp and heart rate is
indirect.
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