THE EFFECTS OF CAFFEINE GUM ADMINISTRATION ON REACTION TIME AND
LOWER BODY PAIN DURING CYCLING TO EXHAUSTION
A Thesis
Presented To
The Graduate Faculty of The University of Akron
In Partial Fulfillment
of the Requirements for the Degree
Master of Science
Andrea Jankowski-Wilkinson
August, 2008
THE EFFECTS OF CAFFEINE GUM ADMINISTRATION ON REACTION TIME
AND LOWER BODY PAIN DURING CYCLING TO EXHAUSTION
Andrea Jankowski-Wilkinson
Thesis
Approved:
Accepted:
____________________________
Advisor
Dr. Ronald Otterstetter
____________________________
Interim Dean of the College
Dr. Cynthia Capers
____________________________
Committee Member
Mrs. Stacey Buser
____________________________
Dean of the Graduate School
Dr. George R Newkome
____________________________
Committee Member
Mrs. Rachele Kappler
____________________________
Date
____________________________
Department Chair
Dr. Victor Pinheiro
ii
ABSTRACT
Caffeine is the most widely consumed drug in the world. In various forms, it has
been shown to elicit some advantageous effects when ingested prior to exercise. Caffeine
has been widely used in the liquid or capsule form for decades now; however caffeine in
the chewing gum form is a much more recent development and hence has less established
research on it. The purpose of this study is to examine the effects of caffeinated chewing
gum on lower body pain and reaction time during exercise. Eight healthy, physically
active male participants between 18 and 32 years of age were recruited to participate.
Participants reported to the laboratory on five occasions. On the first visit, subjects
underwent a graded exercise test on an Excalibur 1300W electronically braked cycle
ergometer until volitional fatigue at which time expired air samples were analyzed for
oxygen and carbon dioxide concentrations via an automated open circuit system to
determine maximal oxygen consumption. The two highest 30-second oxygen
consumption values were averaged to determine maximal oxygen consumption. Over the
next four visits, 200 milligrams of caffeine chewing gum or placebo were administered in
a randomized, counterbalanced, double blind manner at 35 minutes before exercise, 5
minutes before exercise, and 10 minutes following the initiation of exercise. Participants
cycled on an Excalibur electronically braked cycle ergometer at 85% capacity as
iii
determined by expired air samples collected every 10 minutes of exercise which were
analyzed for oxygen and carbon dioxide concentrations via an automated open circuit
system (PARVO, Metabolic Cart, Sandy, Utah). Participants cycled until volitional
fatigue. Lower body pain measurements were obtained every 10 minutes during exercise
via a 1-10 pain scale. Reaction time was measured at three time points via a hand held
psychomotor vigilance test. For statistics, a Mixed Model Analysis was run. There was
no statistical significance in the reduction of reaction time with caffeine administration.
Furthermore, there was not a significant decrease in pain levels with caffeine ingestion.
With a larger sample size, it appears that there may have been a decrease in reaction time
when caffeine is administered fifteen minutes into exercise.
iv
DEDICATION
This study is dedicated to the brave Men and Women of The United States Armed
Forces who have selflessly served our country so that we can all live a life of freedom. To
those who are still with us and to those who have passed, we are forever indebted to you.
Thank you for your courage, and for truly making America the land of the free.
v
ACKNOWLEDGEMENTS
The author would like to give sincere thanks to Dr. Ronald Otterstetter of The University
of Akron for his guidance and support as an advisor and mentor. Thanks to Dr. Gary
Kamimori of Walter Reed Army Institute of Research for his wisdom, and generosity of
his time and supplies. Deep appreciation to Dr. David Newman for his statistical wisdom
and generous donation of his time. A special thanks to all of the fellow researchers,
Morgan Russell, EJ Ryan, Chul-Ho Kim, David Bellar, and Matthew Muller for all of
their hard work and devotion to this research. Lastly, sincere thanks and gratitude to all of
the participants for their time and dedication throughout this process to ensure the success
of the research.
vi
TABLE OF CONTENTS
Page
LIST OF TABLES……………………………………………………………………......ix
LIST OF FIGURES……………………………………………………………………….x
CHAPTER
I. INTRODUCTION ………………………………………………...…………………...1
II. REVIEW OF LITERATURE …….……………...…………………………………….4
III. RESEARCH DESIGN AND METHODS ……………………………………..……10
IV. RESULTS AND DISCUSSION ………………………………………………….…15
V. SUMMARY ………………………………………………………………………….19
BIBLIOGRAPHY………………………………………………………………………..21
APPENDICES…...………………………………………………………………………24
APPENDIX A. HUMAN SUBJECT APPROVAL …………………………………..25
APPENDIX B. INFORMED CONSENT …………………………………………….26
APPENDIX C. BORG SCALE OF PERCEIVED EXERTION ……………………..31
APPENDIX D. PAIN SCALE ………………………………………………………..32
APPENDIX E. PAIN RESULTS ……………………………………………………..33
APPENDIX F. PSYCHOMOTOR VIGILANCE TEST CONTROL TRIAL:
50 MINUTES PRIOR TO EXERCISE………………………………34
APPENDIX G. PSYCHOMOTOR VIGILANCE TEST CONTROL TRIAL:
25 MINUTES PRIOR TO EXERCISE………………………………35
vii
APPENDIX H. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 35 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE…………………………36
APPENDIX I. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 35 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE………………………37
APPENDIX J. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 5 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE………………………38
APPENDIX K. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 5 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE………………………39
APPENDIX L. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 15 MINUTES INTO TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE………………………40
APPENDIX M. PSYCHOMOTOR VIGILANCE TEST :
TREATMENT 15 MINUTES INTO TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE………………………41
viii
LIST OF TABLES
Table
3.1
Page
Participant Profiles …………………………………………………………….11
ix
LIST OF FIGURES
Figure
Page
4.1
Reaction Time Over Time: Treatment versus No Treatment……………………16
4.2
Pain Over Time: Treatment versus No Treatment....…………………………….16
4.3
Reaction Time Over Time ………………………………………………………17
4.4
Pain Over Time ………………………………………………………………….18
x
CHAPTER I
INTRODUCTION
Caffeine is one of the most widely used drugs in the world.35 In moderate doses
(<300 mg) caffeine is well tolerated and few significant side effects have been reported.
Stay Alert chewing gum is a product developed by Amurol Confectioners (Specialty gum
subsidiary of Wrigley’s, Yorkville, IL) that contains 100mg caffeine/stick. Caffeine in
this form is considered a nutritional supplement and requires no additional FDA approval
for use in this form.
Caffeine acts as an adenosine receptor antagonist and several researchers have
demonstrated that it can improve physical and cognitive performance.15, 16 Furthermore,
the ergogenic effects of caffeine are well documented. Caffeine in various forms has been
studied for over 200 years; however there is very little research incorporating this method
of delivery on physical and cognitive performance.
Caffeine delivery methods have been studied very extensively in many forms;
however caffeine delivery using a chewing gum form has not been examined thoroughly.
Caffeine gum delivery is unique because it is absorbed sublingually into the bloodstream.
The advantage of sublingual absorption is that the caffeine is absorbed more quickly than
alternative forms so the effects are felt sooner than alternative methods of absorption.
1
When you chew caffeine gum, the caffeine is released into the saliva and
absorbed through the tissues in the mouth (the buccal cavity) which leads the caffeine
directly into the bloodstream. Through this method of absorption, the effects of the
caffeine reach the brain within approximately three to five minutes; caffeine in the liquid
form can take up to 30-45 minutes.
The purpose of this investigation is to determine the most efficacious time to
administer caffeinated chewing gum in order to maximize reaction time and minimize the
sense of lower body pain. Furthermore, we will then be able to compare the efficacy of
caffeine on exercise when delivered through chewing gum versus alternative forms of
ingestion. This will allow those using the product to better know the ideal timing of
administration.
This study is unique because of the chewing gum component. There has been very
little research performed on the administration of caffeinated gum and the optimal timing
of ingestion. Specifically, what was investigated (through multiple trials) was the
optimal time to start chewing the caffeinated gum, how it affects psycho-motor skills, and
lower body pain/tolerance.
The result of this study could be used to guide the physically active population in
the ideal usage and benefits of caffeinated chewing gum. If significant findings are found
in the reduction of lower body pain, then this product could be used for a variety of
purposes besides the ergogenic effects, such as therapeutic effects. If significant findings
are documented with reaction time, then we can effectively administer the product when
it would be most beneficial for alertness.
2
Research Question #1: How does the ingestion of caffeinated gum affect lower
body pain throughout exercise?
Research Question #2: How does the ingestion of caffeinated gum affect reaction
time?
3
CHAPTER II
REVIEW OF LITERATURE
Caffeine is a natural stimulant that can be found in over sixty leaves,
fruits, and seeds all over the world. It is considered to be the most popular drug in the
world today. 35, 24 Caffeine is thought to be a relatively safe, inexpensive, and readily
available drug. 11, 24 In the practical sense, caffeine can be found in numerous forms
ranging anywhere from drinks, to foods, to chewing gum. We know that caffeine in
various structures can produce some advantageous effects; however there is still question
as to if these effects occur in the same manner when the caffeine is absorbed through the
buccal cavity.
Caffeine is a trimethylxanthine; it is made up of elements of carbon, hydrogen,
nitrogen, and oxygen (C8H10N4O2). 28 The chemical name for caffeine is 3, 7 dihydro- 1,
3, 7-trimethyl-1H-purine-2, 6-dione; it is sometimes abbreviated 1, 3, 7trimethylxanthine. 28 Trimethylxanthine is catabolised by the cytichrin P450 in the liver.
11
Caffeine is further classified as an alkaloid.35 The compound is methylxanthine;
substances in this compound group are easily oxidized to uric acid. 35
Caffeine is widely known for its stimulant effect, or its ability to decrease the
sense of fatigue; it is mostly known for its’ effects on the cerebral cortex and the brain
4
stem in the central nervous system. 34 Caffeine is effective in increasing mental alertness,
and reversing the effects of sleep deprivation. 12 Caffeine is unique from other stimulant
drugs because there is a very low potential for addiction. 12
The mechanism of action is thought to be that caffeine blocks the adenosine
receptors to the brain and other organs. 28 The blocking of the adenosine receptors slows
down the ability of the adenosine to bind to the receptors which ultimately slows down
cellular activity. 28 Adenosine receptors are found throughout the body including in the
heart, brain, smooth muscle, most tissues, and skeletal muscle 11. Due to the unique
nature of caffeine, and the various types of adenosine receptors, it can affect numerous
different tissues and systems in the body. 11 Ingestion of caffeine causes an increase in
neuron firing in the brain, this is largely due to a block of adenosine; in turn this causes
the pituitary gland to go into emergency response mode. This emergency response mode
of the pituitary gland releases hormones which then trigger the adrenal glands to produce
adrenaline. 18 The emergency mode of the pituitary gland is the body’s reaction to fear,
anxiety, or exercise
Adrenaline is released as a result of the stimulated nerve cell. 28 Adrenaline is a
catecholamine that belongs to the family of biogenic amines. It is made in the adrenal
gland of the kidney, is carried in the bloodstream, and mainly affects the autonomous
nervous system. The release of adrenaline in the body has many effects such as an
increase in heart rate, dilation of the pupils, the liver releases extra glucose into the
bloodstream, and secretion of saliva. Adrenaline is an important area to discuss due to its
known affects during exercise.
5
Caffeine in other forms has established analgesic properties which is why it could prove
to be a beneficial supplementation during moderate to high intensity level exercise. It has
been shown that the ingestion of caffeine may enhance the adrenal medullary responses
to normal stressors. 33
Caffeine in forms other than chewing gum is considered to be a rapidly absorbing
drug being absorbed through the stomach lining and reaching the bloodstream is
approximately 45 minutes. 34 Caffeine being absorbed through the stomach lining allows
it to become distributed equally throughout all of the water in the body. The caffeine is
later metabolized in the liver and eventually expelled through the kidneys. The typical
half-life of caffeine is approximately 4 hours under normal conditions.34 On the contrary,
caffeine being absorbed through the buccal cavity, such as through the chewing gum
form will show effects in as little as five minutes; hence the importance of investigating
caffeinated chewing gum more extensively.
Caffeine ingested in the chewing gum form has several advantages based off of
the method of absorption. The caffeine in caffeinated chewing gum form is absorbed
through the buccal cavity in the mouth; this method of ingestion is credited with a faster
absorption rate in part to the highly vascularized buccal cavity. 12, 28 Caffeine in the
chewing gum form also has the advantage of bypassing the intestinal and hepatic
systems; this is due to the fact that the oral veins drain into the vena cava. 12, 28
Ultimately, the bypass of these anatomical areas and the caffeine absorption through the
oral mucosa lead to overall faster absorption rates.
Adenosine concentrations increase during moderate or high intensity exercise.20,5
Peripherally, there are adenosine receptors (A1 and A2a) which are located on sensory
6
nerve endings in the skeletal muscles; these receptors are both influencers of pain
signaling.20,30 The ingestion of caffeine during or slightly prior to exercise alters a
participants perceptions. 7 This alteration could be due to the established analgesic effects
of caffeine during ischemic muscle contractions. 7 Pain that develops as a result of
exercise can theoretically be attributed to muscle contractions which place a mechanical
force on pressure sensitive nociceptors; the mechanical aspect is associated with central
sensitization. 19 Nociceptive pain is elicited when one of two situations occur; harmful
stimulation of normal tissue occurs or when tissue is in a pathological state. 36
Nociceptive pain is often associated with inflamed or damaged tissue (which is likely to
occur during exercise), and furthermore it may occur spontaneously or in response to a
given stimulus. 36
Exercise is commonly used to study pain because it is one of the few activities
that can be used to induce natural skeletal muscle pain. 20 Acute pain is often studied by
artificially inducing symptoms; although this practice allows for a lot of valuable
information to be discovered, a more practical approach could be studying pain in natural
movement patterns such as through exercise. The mechanism of exercise induced skeletal
muscle pain is ill understood and is still being extensively studied for further
understanding.
One theory behind the idea of caffeine masking pain is due to the fact that
caffeine is a nonselective adenosine antagonist.20 The nonselective adenosine antagonist
associated with caffeine has established antinociceptive actions.30 It has yet to be fully
determined if adenosine has any responsibility for the perception of skeletal muscle pain
during exercise.20
7
However, evidence supports the idea that caffeine can play an important role in the
reduction of naturally occurring skeletal muscle pain during exercise; this is thought to be
a natural response of the peripheral nervous system or the central nervous system acting
independently. 20 Skeletal muscle pain is an area that is still being deeply investigated.
Another advantageous effect of caffeine is the mental alertness that commonly
accompanies ingestion. Along with mental alertness, often comes a reduction in reaction
time. The effects of caffeine have shown a positive increase in psychomotor
performance; however the psychomotor responses are known to be dependent on age,
level of alertness, and caffeine abstinence.
18, 8, 24
Exercise at low to moderate intensity
levels has also shown to have a positive influence on psychomotor performance which is
thought to be a direct correlation to an increased mental alertness. 18, 13, 19
One common form of testing reaction time is through administering a
psychomotor vigilance test. Advantages of using this method of testing include ease of
test, portability, multiple participants can use the same unit, inexpensive, relatively
simple to use, and can be tailored to right or left handed users. The psychomotor
vigilance tests have been used extensively for various studies conducted by Walter Reed
Army Institute of Research.
In summary, this study is unique in the sense that we are testing both lower
body pain perception during exercise and reaction action time in relationship to
caffeinated chewing gum. Both of these variables have been extensively studied for
effectiveness with other forms of caffeine ingestion; we are simply examining if the
findings hold true with a different and faster method of absorption. If significant findings
8
are discovered, then we can administer caffeinated chewing gum with a greater sense of
knowledge of its’ overall effects. The benefit of caffeinated gum is that it provides great
ease of ingestion; for example no liquid needs to be consumed and it is simply
convenient. Furthermore, the effects are felt quickly so there is little need to plan too far
in advance for when you may want the caffeine.
9
CHAPTER III
RESEARCH DESIGN AND METHODS
The methods were approved by The University of Akron Institutional Review
Board and Kent State University Institutional Review Board, and all participants were
provided written informed consent. Participants (n=8), were males between 18-32 years
of age, and were recruited via direct contact with the principle investigators. The
participants needed to be non-to-moderate caffeine users; moderate caffeine use was
defined as being less than 330mg/day.
Participants must also have a body fat percentage below 30%; body fat was
measured via a Dual Energy X-Ray Absorptiometry Scan (DEXA Scan) (Hologic QDR
4500 Elite-Acclaim Series, Hologic Inc., Bedford, MA). Furthermore, participants were
excluded from the study if they have a prior history of smoking, have signs or symptoms
of cardiovascular, metabolic, or respiratory disease, or if they are known to have any
cardiovascular, metabolic, or respiratory disease as determined via a health history
questionnaire.
Participants were asked to report to the exercise physiology laboratory on five
separate occasions with a one week washout period between each visit. Prior to reporting
to the laboratory, participants were asked to refrain from eating or drinking (with the
exception of water) for at least eight hours. On the first visit, participants underwent a
10
graded exercise test on an electrically braked cycle ergometer (Excalibur 1300W) until
volitional fatigue at which time expired air samples were analyzed for oxygen and carbon
dioxide concentrations via an automated open circuit system (PARVO, Metabolic Cart,
Sandy, Utah) to determine maximal oxygen consumption.
Table 3.1 Participant Profiles
Participant
Age
Ethinicity
1
30
White
2
21
White
3
32
Asian
4
22
White/AA
5
28
White
6
23
Whte
7
24
White
8
24
White
Average
25.5
Height
69
Inches
74
Inches
69
Inches
69
Inches
70
Inches
70
Inches
70
Inches
69
Inches
70
Inches
Weight
VO2max
82 KG
47.5
110 KG
44.5
66.8 KG
52
106 KG
44
78.5 KG
43.4
75.7 KG
52.2
72.8 KG
46
94 KG
34.1
85.7 KG
45.46
A three-liter syringe (Hans Rudolph Model 5530, Hans Rudolph, Inc., Kansas
City, MO) and known concentration calibration gases were used to calibrate the
automated open circuit system prior to each maximal oxygen consumption test. Heart rate
was continuously measured via a heart rate monitor (Accurex Plus, Polar Electro, Inc.,
Woodbury, NY), and the heart rate values were recorded via telemetry every 30 seconds.
The two highest 30-second oxygen consumption values were averaged to determine
maximal oxygen consumption. The bicycle seat and handle bars were measured for each
individual participant and documented to ensure consistency throughout all of the trials.
11
During the following four visits, two pieces of chewing gum were administered at
three time points (35 minutes prior to exercise, 5 minutes prior to exercise, and 15
minutes following the initiation of exercise). In 3 of the 4 visits, at one of the
administration time points, 200 milligrams of caffeine (Stay Alert chewing gum, Amurol
Confectioners, specialty gum subsidiary of Wrigley’s, Yorkville, IL) was administered.
During one of the four trials (the control trial), placebo gum was administered in all three
of the time points. Caffeine was administered in a randomized, counterbalanced, double
blind manner. The subjects were instructed to chew for five minutes before disposing of
the gum. All of the trials were conducted in a temperature controlled chamber that was
maintained at 23° Celsius.
The participants were given a five minute warm up on the bicycle with a power
output of 50 Watts. Throughout the five minute warm up period, the participants were
ramped until they reached the appropriate wattage. Participants cycled on an Excalibur
electronically braked cycle ergometer (Excalibur 1300W) at 85% capacity as determined
by expired air samples collected every ten minutes of exercise; these air samples were
analyzed for oxygen and carbon dioxide concentrations. Participants were instructed to
cycle between 60-80 revolutions per minute.
Participants cycled until volitional fatigue occurred, that is, until they failed to maintain
the required work output. Failure to maintain the required output was defined as the
participant reaching as low as 40 revolutions per minute.
Ratings of Perceived Exertion and lower body pain were obtained 40 minutes
prior to exercise, five minutes prior to exercise, every ten minutes during exercise, at
exhaustion, and five minutes post-exercise. The Ratings of Perceived Exertion were
12
measured using Borg’s RPE 6-20 scale. The lower body pain was measured using a 0-10
scale where zero was no pain at all and 10 was maximal pain. The participants were
asked to point to a number on the Borg Scale that corresponded to the level of perceived
exertion for their legs, lungs, and an overall sense of exertion. The participants were then
asked to point to a number that corresponded to their level of lower body pain.
To measure vigilance the Palm hand held psychomotor vigilance task (PVT) was
utilized. The Palm-PVT is a test of continuous vigilance. The test is comprised of the
participant reacting to a stimulus (a bulls-eye) which appears in the middle of a Personal
Data Assistant (PDA). The participant’s task is to press a designated key as soon as
possible after the stimulus appears. The amount of time between each stimulus
presentation is randomized between 1, 2, 3, 4, and 5 seconds. The total time of the task is
five minutes. The PVT was administered 50 minutes prior to exercise, 10 minutes prior to
exercise, and 5 minutes post exercise.
During each psychomotor vigilance test (PVT), the participants sat in a chair
within the chamber, facing the wall with one investigator standing behind them to
minimize distractions. Prior to starting the PVT, the participants were given procedural
instructions, and shown which button to push (based off of their dominant hand). The test
from start to finish is five minutes per trial. The PVT’s were always administered in the
same chair and position to maintain consistency. Once the participant completed the postexercise PVT, that individual trial was complete.
Limitations for this study included the small subject population; due to the
repeated measures of the study and procedural constraints, we were only able to test
seven subjects. Another limitation could be that we did not dose by body weight; in other
13
words all of the participants were given the same dose of caffeine regardless of body
composition. Another area that could be a limiting factor is the fitness level of the
participants. Although all of the participants had to demonstrate a body fat percentage of
less than 30% in order to qualify for participation, some of the participants were clearly
more aerobically trained than others.
14
CHAPTER IV
RESULTS AND DISCUSSION
This was a repeated measures study in which the subjects were not all measured at all
time points (due to the differences in cycling time to exhaustion); therefore a Repeated
Measures ANOVA was not applicable. In order to analyze this study, Mixed Model
analyses were conducted. Mixed Models, also referred to as HLM and Individual Growth
Models allows one to model the appropriate covariance matrix while allowing for
different test times for each subject.
One research question was that there would be a significant decrease in reaction
time with caffeine administration over the exercise period. This hypotheses was not
statistically significant p=0.579 with an F=0.282 and a R2=0.003. As can be seen in the
figure below (Figure 4.1), the reaction time was slightly but not significantly faster with
the ingestion of caffeine.
Another reseach area was would there be significant less increase in pain with
caffeine administration over the exercise period? This hypothesis was not statistically
significant p=0.993 with an F=0.0001 and a R2=0.000. As can be seen below (Figure
4.2), pain levels over time seem to be almost identical regardless if the participant
ingested caffeine or not.
15
Figure 4.1 Reaction Time Over Time: Treatment versus No Treatment
Figure 4.2 Pain Over Time: Treatment versus No Treatment
The next research question was would there be a differential effect in reaction
time depending on if the caffeine was administered at 35 minutes prior to exercise, five
minutes prior to exercise, or fifteen minutes into exercise? These results were not
statistically significant p=0.703 with an F=0.471 and a R2=0.005.
16
As can be seen below (Figure 4.3) in the figure, all of the reaction times were consistantly
close with the exception of the participants who ingested the caffeine fifteen minutes
after exercise had begun. With a larger sample or a smaller standard error this treatment
group might have had significantly faster reaction times.
Figure 4.3 Reaction Time Over Time
The final area of exploration was whether or not there would be a differntial effect
in reported pain levels depending on if the caffeine was administered at 35 minutes prior
to exercise, five minutes prior to exercise, or fifteen minutes into exercise. There was not
statistical significance in this area p=0.943 with an F=0.129 and a R2=0.001. As can be
seen below (Figure 4.4), the pain levels increase almost identically regardless of the
caffeine treatment.
17
Figure 4.4 Pain Over Time
Previous research has shown that anxiety coupled with caffeine ingestion
could play an important role in pain perception.10, 20 It has been shown that a dose of 10
milligrams of caffeine per kilogram of bodyweight significantly reduced pain in the
quadriceps muscles during cycling.10 Further experimentation showed that doses as small
as 5 milligrams of caffeine per kilogram of bodyweight produced similar effects in the
reduction of leg pain.10, 20 These previous studies were based off of cycling at a moderate
intensity that was defined as being 60% of the participants’ maximal volume of oxygen
consumption (VO2max).
Further studies that were conducted based off of the research findings of caffeine
related hypoalgesia while exercising at 60% of VO2max, found similar reduction in leg
pain when participants exercised at 80% of VO2max.10 It has been documented that when
compared to a placebo, a 5 milligram dose of caffeine per kilogram of body weight has
very significant hypoalgesic effects during cycling. 10 I believe that given a larger
population size and dosing the caffeine by body weight would have elicited similar
analgesic results as seen with previous research.
18
CHAPTER V
SUMMARY
Since caffeine is such a widely used substance in the world today, it is beneficial
to understand all of the advantages that it may provide. Furthermore, understanding when
to use caffeine to experience optimal performance of the drug is of equal importance. We
have known for many years that caffeine has some advantageous effects, however the
development and research of caffeinated chewing gum is relatively modern, and therefore
requires further research to fully prove all of its’ benefits.
The purpose of this study was to establish if there was a decrease in lower body
pain with the ingestion of caffeine throughout exercise, and if so at what time point
should the caffeinated gum be taken. The secondary purpose was to establish if there was
a relationship between reaction time, exercise, and caffeinated gum, and again if there
was a relationship established then at what time point is ingestion most advantageous.
There is a lot of room for research in this area; dosing by body weight, and a
larger population of participants would be beneficial. Another area to consider in future
research would be to look at recovery time post exercise to see if caffeine helps to speed
up that process. Looking at the exercise training history of the participants would be
another area to explore to see if those who are anaerobically trained are experiencing the
same results as those who are aerobically trained.
19
This area of research is important because caffeinated chewing gum has such a fast
absorption rate that it could be beneficial to many different populations throughout
various situations. Caffeine has become a substance that people not only enjoy on a
regular basis, but perhaps a substance that could help to increase mental alertness and
performance.
20
BIBLIOGRAPHY
1. Amendola, C., Garrrieli, J. & Leiberman. (1998). Caffeine’s effect on performance
and mood are independent of age and gender. Nutr Neuroscience, 1, 269.
2.Bell, D. & Mcmellan. (2002). Exercise endurance 1, 3, and 6 H after caffeine ingestion
in users and nonusers. J. applied physiology, 93, 1127.
3. Bender, V.L., McGlynn, L. (1976). The effect of various levels of strenuous to
exhausting exercise on reaction time. European journal of applied physiology. 35:95-10.
4. Cook, D.B. (2006). Physical activity and pain. In E.D. Acevedo & P. Ekkekakis
(Eds.), Psychobiology of physical activity (pp. 203-217). Champaign, IL: Human
Kinetics.
5.Costa F, Diedrich A., Johnson B., Sulur P., Farley, G., Biaggioni, I.: Adenosine, a
metabolic trigger of the exercise pressor reflex in humans. Hypertension 37:917-922,
2001.
6. Dews P.B. (1984). Metabolism and Kinetics. In: Dews PB (ed) Caffeine. SpringerVerlag, New York.
7. Doherty, M., Smith, P.M. (2005). Effects of caffeine ingestion on rating of perceived
exertion during and after exercise: a meta-analysis. Scandinavian journal of medicine &
science in sports. 15: 69-78.
8. Fine, B.J., Kobrick, L., Lieberman, H.R., Marlowe, B., Riley, R.H., Tharion, W.J.
(1994). Effects of caffeine or diphenhydramine on visual vigilance.
Psychopharmacology. 114:233-238.
9. Freholm, B. et al. (1999). Actions of caffeine in the brain with special reference to
factors that contribute to its widespread use. Pharmacology rev, 51, 83.
10. Gliottoni, R., Motl, R. (2008). Effect of caffeine on leg-muscle pain during intense
cycling exercise: possible role of anxiety sensitivity. International Journal of Sport
Nutrition and Exercise Metabolism, 18, 103-115.
21
11. Graham, T. (2001). Caffeine and exercise metabolism, endurance, and performance.
Sports Med. 31(11): 785-807.
12. Graham & Spriet. (1995). Metabolic, catecholamine, and exercise performance
responses to various doses of caffeine. J. applied physiology, 78, 867.
13. Levitt, S., Gutin, B. (1971). Multiple-choice reaction time and movement time during
physical exertion. Res quart. 42:406-410.
14. Lieberman et al. (1987).The effects of low doses of caffeine on human performance
and mood. Psycho-pharmacology, 92, 308.
15. Kamimori, G.H., Karyekar, C.S., Otterstetter, R., Cox, D.S., Balking, T.J., Belenky,
G.L., Eddington, N.D. (2001). The rate of absorption and relative bioavailability of
caffeine administered in chewing gum versus capsules to normal healthy volunteers.
International journal of pharmaceutics. 234: 159-167.
16. Kamimori, G.H., Lugo, S.T., Penetar, D.M., Chamberlain, A.C., Brunhart, G.E.,
Brunhart, A.E., Eddington, N.D. (1995) Dose-dependent caffeine pharmacokinetics
during severe sleep deprivation in humans. International journal clinical pharmacology.
Toxicol, Ther. 33 (1), 82-86.
17. Keogh, E., & Chaloner, N. (2002). The moderatinf effect of anxiety sensitivity on
caffeine induced hypoalgesia in healthy women. Psychopharmacology (Berlin), 164, 42431.
18. Kruk, B., Chmura, J., Krzeminski, K., Ziemba, A.W., Nazar, K., Pekkarinen, H.,
Kaciuba-Uscilko, H. (2001). Influence of caffeine, cold and exercise on multiple choice
reaction time. Psychopharmacology. 15: 197-204.
19. Lamond, N., Jay, S.M., Dorrian, J., Ferguson, S.A., Roach, G.D., Dawson, Drew.
(2008). The sensitivity of a palm-based psychovigilance motor task to sever sleep loss.
Behavior research methods. 40 (1), 347-352.
20. Motl, R.W., O’Connor, P.J., & Dishman, R.K. (2003). Effect of caffeine on
perceptions of leg muscle pain during moderate intensity cycling exercise. Journal of
Pain, 4, 316-321.
21. Myers, DE., Shaikh, Z., Zullo, TG. (1997). Hypoalgesic effect of caffeine in
experimental ischemic muscle contraction pain. Headache 37:654-658, 1997.
22. Pasman et al. (1995). The effects of different dosages of caffeine on endurance
performance times. I. J. sports med, 16, 225.
22
23. Perkins, R., Williams, M.H. (1975). Effect of caffeine upon maximal muscular
endurance of females. Med sci sports. 7:221-4.
24. Rees, K., Allen, D., Lader, M. (1999). The influences of age and caffeine on
psychomotor and cognitive function. Psychopharmacology. 145: 181-188.
25. Reiss, S., Peterson, R.A., Gursky, D.M., & McNally, R.J. (1986). Anxiety sensitivity,
anxiety frequency and the prediction of fearfulness. Behaviour Research and Therapy,
24, 1-8.
26. Robertson, D. & Curatolo P. (1984). The cardiovascular effects of caffeine. In: Dews
PB (ed) Caffeine. Springer-Verlag, New York.
27. Serafin, W. (1996). Drugs used in the treatment of asthma: methylxanthines. The
Pharmacological Basis of Therapeutics, 9th edition. Macmillan Publishing Company,
New York.
28. Shargel, L., Yu, A. (1999). Applied biopharmaceutics and pharmacokinetics.
Appleton and Lange, 119-120.
29. Spreit et al. (1992). Caffeine ingestion and muscle metabolism during prolonged
exercise in humans, Am. J. physiology, 262, E891.
30. Sawynok, J., Adenosine receptor activation and nociception. European journal of
pharmacology, 347, 1-11, 1998
31. Syed, S.A., Kamimori, G.H., Kelly, W., Eddington, N.D. (2005). Multiple dose
pharmacokinetics of caffeine administered in chewing gum to normal healthy volunteers,
Biopharmaceutics & drug disposition. 26: 403-409.
32. VanSoeren, M & Graham (1998). Effect of caffeine on metabolism, exercise
endurance, and catecholamine response after withdrawal. J applied physiology, 85, 1493.
33. Yeragani, V. M.D., Krishnan, S., Engels, H.J. Ph.D., & Gretebeck, R., Ph.D. (2005).
Effects of caffeine on linear and nonlinear measure of heart rate variability before and
after exercise. Depression and anxiety. 21:130-134.
34. Virtual Mass Spectrometry. Available at http://massspec.chem.cmu.edu/VMSL/Caffeine/Caffeine_effects.htm. Accessed July 19, 2008.
35. How Caffeine Effects the Body. Available at http://www.faqs.org/nutrition/CaDe/Caffeine.html. Accessed July 18, 2008.
36. Neuromuscular Website for WUSTL. Available at
http://neuromuscular.wustl.edu/mother/mpain.html. Accessed July 17, 2008.
23
APPENDICES
24
APPENDIX A
HUMAN SUBJECTS APPROVAL
25
APPENDIX B
INFORMED CONSENT
Title of Study: “The Effects of Caffeine Administration Timing on Cycling to
Exhaustion”
Introduction: You are invited to participate in a research study designed and conducted
by Andrea Jankowski-Wilkinson and Morgan Russell, Masters’ students enrolled in the
Exercise Physiology program at The University of Akron in the Department of Sport
Science and Wellness Education and Edward Ryan, Doctoral student enrolled in the
Exercise, Leisure and Sport program at Kent State University, under the advisement of
Dr. Ronald Otterstetter, faculty member at The University of Akron in the Department of
Sport Science and Wellness Education.
Purpose: The main objective for this investigation is to determine the best time to
administer caffeinated chewing gum in order to see how it affects exercise performance
on a bicycle. This study will specifically look at the effect caffeine has on the body at
rest and during exercise, how fast fatigue occurs, and mental alertness.
Procedure: Ten subjects will individually participate in the research. If you volunteer
for this study you will be required to take part in a preliminary visit and four testing trials.
The preliminary visit will last approximately sixty minutes and each of the four testing
trials will last approximately ninety minutes. During the preliminary visit, the testing
protocol will be explained and you will complete a health history questionnaire as well as
a Dual Energy X-ray Absorptiometry (DEXA) scan to determine baseline body
composition. You will undergo a graded exercise test on a bicycle until you cannot
exercise any longer to determine your highest level of fitness. The bicycle will be set to
increase in resistance every minute. Throughout the test, you will be equipped with a
mouthpiece similar to a scuba-diving snorkel, which you will breathe through for the
entire exercise session. You will also be equipped with a heart rate monitor and a blood
pressure cuff for the entire exercise session.
The four testing trials will be separated by seven days, in which data will be collected.
You will chew either two pieces of caffeinated gum containing 100 milligrams of
caffeine each, or a placebo, 35 minutes pre-exercise, 5 minutes pre-exercise, and 10
minutes following the initiation of exercise. You will be required to complete a
cardiovascular endurance capacity test.
26
The cardiovascular endurance test will be performed on a bicycle. You will cycle at a set
intensity that will be predetermined until you cannot cycle any longer. During this test,
the amount of oxygen that you breathe in will be measured using the mouthpiece every
10 minutes, heart rate will be measured, the effort you are cycling at will be determined
using a chart, blood glucose and lactate levels will be measured by a finger prick,
perceived leg pain will be determined by you determining your level of leg pain
according to numbers on a chart, and reaction time will be determined using a Palm-held
psychomotor vigilance task. The task will require you to react to a stimulus (a bulls-eye),
which appears in the middle of a Personal Data Assistant (PDA). Your task will be to
press a designated key as soon as possible after the stimulus appears, while on the
bicycle.
Two blood specimens of 5 ml each will be drawn three times during the trial. A total of
30 ml will be drawn, which is approximately one tablespoon per trial. The blood
specimens will be taken 40 minutes pre-exercise, immediately pre-exercise, and
immediately post-exercise.
Blood glucose and blood lactate levels will be measured by a glucometer and lactate
analyzer. Your finger will be pricked using stick that looks like a pen and then the blood
will immediately be analyzed. You will be pricked 40 minutes pre-exercise, immediately
pre-exercise, and every ten minutes during exercise.
Prior to the four testing trials, you will be asked to not eat for 8 hours before each trial
and to not consume any alcohol or caffeine containing drinks for 24 hours before each
trial.
Inclusion: Healthy males between the ages of 18 and 32 years.
Exclusion: A Health History Questionnaire will be used to determine exclusion criteria.
If you answer yes to any question on the questionnaire and do not fall within acceptable
quantified limits, you will be disqualified from the study. The three quantified items on
the health history questionnaire are alcohol consumption (< 3 drinks per day), caffeine
consumption (< 300 mg per day), and if you have had mononucleosis within six months
of first trial date. You will be excluded if you use caffeine supplements, smoke, show
signs or symptoms of cardiovascular, metabolic, or respiratory diseases or you have a
known cardiovascular, metabolic, or respiratory disease. You will also be excluded if
you are >30% body fat, due to an increased chance of a cardiac event.
Risk and Discomfort as Related to Caffeine: Risks associated with this investigation
are related to the ingestion of caffeine. Although the caffeine doses used in this study are
similar to those encountered in everyday life, over the counter supplements have the
potential for minor side effects. Side effects for caffeine may include the possibility of
headache, dizziness, nausea, and muscle tremor. Individuals who do not consume
caffeine on a regular basis may be more prone to side effects than those who are habitual
caffeine users. In addition, chewing gum may cause dental fillings to become loose.
27
Risk and Discomfort as Related to Blood Draws: Mild discomfort, or bruising due to
venipuncture is possible. There is a slight risk of infection similar to any puncture in the
skin, which will be minimized by using a sterile technique.
The universal precautions to avoid transmission of blood borne pathogens between tester
and subject will be observed. Venipuncture will be performed by trained, experienced
personnel. Phlebotomy competency training will be completed and documented for all
individuals performing blood draws. In the event of a medical emergency, all researchers
are CPR, First Aid, and AED trained and certified. Should an emergency occur, the
researchers will activate EMS.
Risk and Discomfort as Related to Dual Energy X-Ray Absorptiometry: There is
minimal radiation exposure through the DEXA scans. The amount of radiation in this
investigation is less than 1/1000th of the exposure associated with an average dental X-ray
(DEXA=1mR/18 sec vs. Dental X-ray=1138mR).
Risk and Discomfort as Related to Exercise Tests: Mild and localized discomfort, not
exceeding that incurred during a normal exercise session, associated with delayed onset
muscle soreness due to exercise can be expected. You may experience fatigue and
lightheadedness due to exercise. Throughout the test your nose will be clamped and you
will breathe through a tube, which you may find uncomfortable.
A health history will be taken to screen out anyone for who strenuous exercise may pose
a higher than expected risk. It is important that you provide truthful and accurate
information so as to not put yourself at unnecessary risk.
Investigators have completed over 100 VO2max tests without a subject injury or critical
event. An investigator will be monitoring the computer, as to stop the test at any point
that the subject requests or if the researchers feels it is unsafe for you to continue based
on guidelines set forth by the American College of Sports Medicine.
The risk of serious injury is no greater than that which you may experience with a very
intense, physical workout. There is an extremely small chance of a serious medical
condition occurring, and according to National statistics, 4 out of every 10,000 people
may experience a heart attack and 1 out of every 10,000 people may experience sudden
death when engaging in intense physical exercise/exertion. You should inform the
researchers immediately if you start to have pains in your chest, shoulder or legs, feel
dizzy or weak, and experience any shortness of breath, difficulty breathing, or other
distressing symptoms during the testing procedure.
Risk and Discomfort as Related to Finger Pricks: Mild discomfort or soreness may
occur due to finger pricks. There is a slight risk of infection similar to any puncture in the
skin, which will be minimized by using a sterile technique.
28
The universal precautions to avoid transmission of blood borne pathogens between tester
and subject will be observed. Finger pricks will be performed by the researchers.
Benefits: Participating in this study will allow you to learn more about your fitness level
from the bicycle exercise test, as well as your personal body composition and bone
density via a DEXA scan.
Payments for Participation: You will be monetarily compensated upon the completion
of your individual participation in the study. You will be compensated $200, broken
down into the following increments based on the completion of each trial: $25 for
successful completion of trial 1, $25 for successful completion of trial 2, $50 for
successful completion of trial 3 and $100 for successful completion of trial 4. If you are
unable to participate in all four trials, your compensation will be prorated accordingly.
Right to refuse or withdraw: Participation in the research is voluntary. You may
withdraw consent and discontinue participation in the study at any time without any
consequence to you.
Anonymous and Confidential Data Collection: Any identifying information collected
will be kept in a locked file cabinet, and only the researchers will have access to the data.
As a participant, you will not be individually identified in any publication or presentation
of the research results. Only comprehensive data will be used. To insure your privacy,
the information found in his study will be subject to the confidentiality and privacy
regulations of The University of Akron and Kent State University.
Confidentiality of records: The project director will store all of your information in a
locked research file and will identify you only by a number. The project director will
keep the number key connecting your name to your number in a separate secure file. The
data will be kept in two secure locations; The University of Akron, in Memorial Hall
room 60E, and at Kent State University in the gym annex room 163. The data will be
kept for three years and then shredded.
Who to contact with questions: If you have any questions at any time, you may contact
either of the researchers at (330) 972-7747 or our advisor, Dr. Ronald Otterstetter in the
Department of Sport Science and Wellness Education at (330) 972-7738. This project has
been reviewed and approved by The University of Akron Institutional Review Board. If
you have any questions about your rights as a research participant, you may call Sharon
McWhorter, the Associate Director of Research Services & Sponsored Programs at The
University of Akron, at (330) 972-8311 of 1-888-232-8790.
Thank you for your willingness to participate in this study.
Andrea Jankowski-Wilkinson, B.S.
Researcher
Morgan Russell, B.S.
Researcher
29
Edward Ryan, M.S.
Researcher
Ron Otterstetter, PhD
Researcher, Advisor
Acceptance & Signature: I have read the information provided above and all of my
questions have been answered. I voluntarily agree to participate in this study. I will
receive a copy of this consent form for my information.
_________________________________
Participant Signature
Date:_____________________
_________________________________
Signature of Witness
Date:_____________________
30
APPENDIX C
BORG SCALE OF PERCEIVED EXERTION
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
very, very light
very light
fairly light
somewhat hard
hard
very hard
very, very hard
31
APPENDIX D
PAIN SCALE
0
No Pain
1
Onset of Pain
2
3
Mild Pain
4
5
Moderate Pain
6
7
Severe Pain
8
9
Barely Tolerable
10
Overwhelming/Unable to Continue
32
APPENDIX E
PAIN RATINGS
P1
P2
P3
P4
P5
P6
P7
P8
Average
-40
0
0
0
0
0
0
0
0
0
-10
0
0
0
0
0
0
0
0
0
P1
P2
P3
P4
P5
P6
P7
P8
Average
-40
0
0
0
0
0
0
0
0
0
-10
0
0
0
0
0
0
0
0
0
P1
P2
P3
P4
P5
P6
P7
P8
Average
-40
0
0
0
0
0
0
0
0
0
-10
0
0
0
0
0
0
0
0
0
P1
P2
P3
P4
P5
P6
P7
P8
Average
-40
0
0
0
0
0
0
0
0
0
-10
0
0
0
0
0
0
0
0
0
Pain Ratings Placebo Trial
10
20
30
3
6
8
4
5
6
2
4
5
6
6
8
9
5
7
8
7
9
3
6
6
4.5
6.43
7
Pain Ratings -35
10
20
30
5
7
8
2
4
6
0
4
6
6
10
8
9
5
6
8
6
9
2
4
5
4.25
6.63
6.6
Pain Ratings -5
10
20
30
3
6
6
5
6
7
3
6
9
7
10
6
8
9
5
6
7
4
6
2
5
5
4.38
6.63
7.17
Pain Ratings +15
10
20
30
4
5
8
4
6
6
1
2
5
6
10
6
9
9
7
7
7
5
9
2
5
5
7
6.63
6.67
33
40
50
8
7
7.5
40
50
8
6
7
40
8
50
8
40
9
50
9
9
9
APPENDIX F
PSYCHOMOTOR VIGILANCE TEST CONTROL TRIAL:
50 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
89
88
88
87
88
85
88
85
87.25
Mean RT
0.284
0.271
0.312
0.273
0.273
0.405
0.33
0.273
0.303
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.21
0.19
0.24
0.19
0.21
0.24
0.22
0.17
0.19
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Max RT
0.50
0.45
0.69
0.71
0.41
2.01
0.54
0.70
0.60
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.057
0.04
0.07
0.081
0.051
0.251
0.067
0.084
0.088
Median
0.27
0.27
0.30
0.25
0.26
0.32
0.31
0.26
0.27
Duration
305
302
303
303
301
302
302
301
303
Major
Lapses
0
0
0
0
0
0
0
0
0
34
Invalid RS
0
1
0
1
0
1
0
2
1
Minor
Lapses
1
0
3
2
0
13
4
2
3
False
Starts
0
1
0
1
0
1
0
2
1
APPENDIX G
PSYCHOMOTOR VIGILANCE TEST CONTROL TRIAL:
25 MINUTES PRIOR TO EXERCISE
Mean
RT
0.268
0.281
0.324
0.253
0.268
0.336
0.283
0.281
0.275
Std
Dev
0.034
0.032
0.139
0.048
0.066
0.079
0.046
0.089
0.062
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
89
89
87
86
87
87
88
88
88.5
Median
0.26
0.28
0.3
0.24
0.25
0.32
0.28
0.27
0.27
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.21
0.22
0.24
0.19
0.20
0.23
0.21
0.17
0.19
Max
RT
0.46
0.43
1.48
0.46
0.67
0.67
0.45
0.78
0.62
Duration
304
305
306
302
304
302
304
303
303.5
Invalid
RS
0
0
0
2
1
0
1
2
1
False
Starts
0
0
0
0
1
0
1
2
1
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
2
0
0
0
0
0
Others
0
0
0
0
0
0
0
0
0
Major
Lapses
0
0
0
0
0
0
0
0
0
Minor
Lapses
0
0
3
0
2
3
0
3
1.5
Deadlines
0
0
0
0
0
0
0
0
0
35
APPENDIX H
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 35 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
88
88
88
89
89
87
87
88
88
Mean RT
0.292
0.273
0.321
0.274
0.282
0.347
0.307
0.253
0.273
Std Dev
0.057
0.042
0.170
0.086
0.061
0.183
0.061
0.067
0.620
Median
0.28
0.27
0.28
0.26
0.78
0.31
0.29
0.24
0.26
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.21
0.20
0.23
0.20
0.21
0.23
0.21
0.16
0.19
Max RT
0.54
0.42
1.70
0.97
0.53
1.84
0.58
0.44
0.49
Duration
301
301
304
304
304
303
302
302
301.5
Invalid
RS
0
1
0
0
0
1
2
1
0.5
False
Starts
0
1
0
0
0
1
2
1
0.5
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Others
0
0
0
0
0
0
0
0
0
Major
Lapses
0
0
0
0
0
0
0
0
0
Minor
Lapses
1
0
3
1
1
5
2
0
0.5
Deadlines
0
0
0
0
0
0
0
0
0
36
APPENDIX I
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 35 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
87
89
87
89
88
88
87
85
86
Mean RT
0.287
0.258
0.291
0.253
0.282
0.303
0.282
0.284
0.286
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.21
0.2
0.23
0.19
0.18
0.23
0.21
0.17
0.19
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Max RT
0.41
0.50
0.73
0.38
0.82
0.83
0.42
0.70
0.56
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.049
0.041
0.074
0.035
0.083
0.073
0.038
0.099
0.074
Median
0.28
0.25
0.28
0.25
0.26
0.29
0.28
0.25
0.27
Duration
302
302
303
306
304
302
304
300
301
Major
Lapses
0
0
0
0
0
0
0
0
0
37
Invalid RS
0
0
0
1
1
0
1
1
0.5
Minor
Lapses
0
1
3
0
2
2
0
4
2
False
Starts
0
0
0
1
1
0
1
1
0.5
Deadlines
0
0
0
0
0
0
0
0
0
APPENDIX J
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 5 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
88
89
89
86
89
88
88
86
87
Mean RT
0.313
0.278
0.263
0.296
0.277
0.323
0.317
0.330
0.322
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.23
0.21
0.21
0.2
0.21
0.22
0.21
0.19
0.21
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Max RT
0.95
0.48
0.48
0.56
0.53
1.71
0.72
0.69
0.82
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.094
0.045
0.037
0.063
0.058
0.163
0.078
0.102
0.098
Median
0.29
0.27
0.26
0.28
0.26
0.30
0.30
0.31
0.30
Duration
303
304
305
302
304
303
302
301
302
Major
Lapses
0
0
0
0
0
0
0
0
0
38
Invalid RS
0
0
1
1
0
0
0
1
0.5
Minor
Lapses
0
0
0
1
1
2
3
5
2.5
False
Starts
0
0
1
1
0
0
0
1
0.5
Deadlines
0
0
0
0
0
0
0
0
0
APPENDIX K
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 5 MINUTES PRIOR TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
87
83
89
89
87
82
89
82
85
Mean RT
0.28
0.273
0.283
0.278
0.284
0.304
0.273
0.281
0.281
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.2
0.16
0.23
0.22
0.2
0.22
0.21
0.18
0.19
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Max RT
0.65
2.15
0.79
0.48
0.7
0.48
0.39
0.72
0.69
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.05
0.245
0.061
0.047
0.075
0.066
0.041
0.088
0.069
Median
0.28
0.23
0.27
0.27
0.26
0.28
0.27
0.25
0.27
Duration
302
304
304
305
302
302
304
301
301.5
Major
Lapses
0
0
0
0
0
0
0
0
0
39
Invalid RS
0
4
0
1
0
4
0
6
3
Minor
Lapses
0
2
1
0
2
0
0
3
1.5
False
Starts
0
4
0
1
0
4
0
6
3
Deadlines
0
0
0
0
0
0
0
0
0
APPENDIX L
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 15 MINUTES INTO TO EXERCISE TRIAL:
PVT 50 MINUTES PRIOR TO EXERCISE
-50
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
87
89
88
89
88
87
86
85
86
Mean RT
0.348
0.265
0.259
0.272
0.277
0.317
0.290
0.281
0.315
-50
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.23
0.20
0.20
0.19
0.19
0.20
0.21
0.17
0.20
-50
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
1
0.5
Max RT
0.72
0.47
0.5
0.67
0.48
0.98
0.41
4.27
2.495
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.093
0.042
0.046
0.059
0.054
0.101
0.052
0.442
0.268
Median
0.32
0.26
0.25
0.26
0.265
0.3
0.28
0.22
0.27
Duration
302
302
303
304
303
305
0.298
302
302
Major
Lapses
0
0
0
0
0
0
0
1
0.5
40
Invalid RS
0
0
0
1
1
0
1
2
1
Minor
Lapses
7
0
1
1
0
3
0
2
4.5
False
Starts
0
0
0
1
1
0
1
1
0.5
Deadlines
0
0
0
0
0
0
0
0
0
APPENDIX M
PSYCHOMOTOR VIGILANCE TEST
TREATMENT 15 MINUTES INTO TO EXERCISE TRIAL:
PVT 25 MINUTES PRIOR TO EXERCISE
P1
P2
P3
P4
P5
P6
P7
P8
Average
Valid RS
88
89
88
87
88
88
87
87
87.5
Mean RT
0.338
0.280
0.293
0.315
0.294
0.333
0.273
0.250
0.294
P1
P2
P3
P4
P5
P6
P7
P8
Average
Min RT
0.23
0.20
0.22
0.19
0.19
0.21
0.21
0.18
0.21
P1
P2
P3
P4
P5
P6
P7
P8
Average
Anticipations
0
0
0
0
0
0
0
0
0
Max RT
0.78
0.45
0.60
4.70
0.74
1.15
0.48
0.57
0.68
Others
0
0
0
0
0
0
0
0
0
Std Dev
0.089
0.038
0.046
0.478
0.086
0.120
0.046
0.067
0.078
Median
0.33
0.27
0.29
0.26
0.27
0.31
0.26
0.23
0.28
Duration
305
305
302
303
301
303
0.303
302
303
Major
Lapses
0
0
0
1
0
0
0
0
0
41
Invalid RS
0
0
0
1
0
0
1
1
0.5
Minor
Lapses
4
0
1
2
3
5
0
2
3
False
Starts
0
0
0
1
0
0
1
1
0.5
Deadlines
0
0
0
0
0
0
0
0
0