ATHLETE KNOWLEDGE AND USE OF POST-EXERCISE REHYDRATION
DRINKS

A THESIS
Submitted to the Faculty of the School of Graduate Studies
and Research
of
California University of Pennsylvania in partial
fulfillment of the requirements for the degree of
Master of Science

by
Joshua Gregoire

Research Advisor, Dr. Robert Kane
California, Pennsylvania
2011

ii

iii

ACKNOWLEDGEMENTS
I would like to thank my committee members, Dr. Robert
Kane, EdD, PT, ATC, Chris T. Harman, EdD, ATC, and Thomas
F. West, PhD, ATC, for all of their assistance in the
various aspects involved in this research. I would also
like to thank Nancy Groh, EdD LAT, ATC for her help in
formulating the early parts of this thesis. Lastly, I would
like to thank Dan Tarara, MS, ATC, LAT for his unwavering
support in helping me from the time I was a junior in
undergraduate up until the present. I would not have done
this thesis if not for your help in selecting this topic
for your class my junior year.

iv
TABLE OF CONTENTS

Page
SIGNATURE PAGE

. . . . . . . . . . . . . . . . ii

AKNOWLEDGEMENTS . . . . . . . . . . . . . . . . iii
TABLE OF CONTENTS
LIST OF TABLES
INTRODUCTION
METHODS

. . . . . . . . . . . . . . . iv

. . . . . . . . . . . . . . . . vii

. . . . . . . . . . . . . . . . . 1

. . . . . . . . . . . . . . . . . . . 5

Research Design
Subjects

. . . . . . . . . . . . . . . 5

. . . . . . . . . . . . . . . . . . 6

Preliminary Research

. . . . . . . . . . . . . 6

Instruments . . . . . . . . . . . . . . . . . 7
Procedure . . . . . . . . . . . . . . . . . . 8
Hypotheses. . . . . . . . . . . . . . . . . . 8
Data Analysis
RESULTS

. . . . . . . . . . . . . . . . 9

. . . . . . . . . . . . . . . . . . . 10

Demographic Information
Hypothesis Testing

. . . . . . . . . . . . 10

. . . . . . . . . . . . . . 11

Additional Findings . . . . . . . . . . . . . . 15
DISCUSSION . . . . . . . . . . . . . . . . . . 17
Discussion Results

. . . . . . . . . . . . . . 17

Conclusions . . . . . . . . . . . . . . . . . 24
Recommendations

. . . . . . . . . . . . . . . 26

v
REFERENCES . . . . . . . . . . . . . . . . . . 27
APPENDICES . . . . . . . . . . . . . . . . . . 29
APPENDIX A: Review of Literature

. . . . . . . . . 30

Benefits of Post-exercise Rehydration Drinks . . . . 32
Dehydration. . . . . . . . . . . . . . . . 32
Starting Exercise Hypohydrated . . . . . . . 34
Returning to Fluid Balance . . . . . . . . . 34
Nutritional Needs of Athletes . . . . . . . . . 35
Nutrients in Sweat

. . . . . . . . . . . . . 36

Current Post -Exercise Rehydration Drinks
Fluid-Replacement Drinks

. . . . . . . . . . 37

Carbohydrate -Protein drinks
Milk

. . . 37

. . . . . . . . . 38

. . . . . . . . . . . . . . . . . . . 39

Research Trials of Current Rehyd ration Drinks . 39
Athlete Knowledge
Summary

. . . . . . . . . . . . . . 47

. . . . . . . . . . . . . . . . . . . 48

APPENDIX B: The Problem . . . . . . . . . . . . . 49
Statement of the Problem . . . . . . . . . . . 50
Definition of Terms . . . . . . . . . . . . . . 50
Basic Assumptions . . . . . . . . . . . . . . . 51
Limitations of the Study . . . . . . . . . . . . 51
Significance of the Study. . . . . . . . . . . . 52
APPENDIX C: Additional Methods . . . . . . . . . . 53
IRB: California University of Pennsylvania (C1) . . . 54

vi
Cover Letter to Participant (C2) . . . . . . . . . 66
Cover Letter to Athletic Director(C3) . . . . . . . 68
Response Letter from Athletic Director (C4)

. . . . 70

High Point University Liaison Letter (C5) . . . . . 72
Survey (C6) . . . . . . . . . . . . . . . . . 74
REFERENCES . . . . . . . . . . . . . . . . . . 86
ABSTRACT

. . . . . . . . . . . . . . . . . . 91

vii
LIST OF TABLES
Table

Title

Page

1

Participants per Team . . . . . . . . . 11

2

Age of Participants . . . . . . . . . . 11

3

One-Way ANOVA between Knowledge Score
and Sport Played. . . . . . . . . . . . 12

4

T-Test Between Drink Knowledge and Gender . 13

5

Chi-Square Comparison of PERD Usage
and Sport . . . . . . . . . . . . . . 13

6

Chi-Square Comparing PERD Usage and Gender.

14

7

Times Per Week PERD is Consumed. . . . . . 15

8

Types of PERD Used

9

Post-Exercise Rehydration Drink Category. . 16

10

Post-Exercise Rehydration Use by Team . . . 18

11

Dehydration’s Impact on Performance. . . . 21

12

Which of these does NOT dehydrate you

. . . . . . . . . . 15

faster? . . . . . . . . . . . . . . . 21
13

Water is NOT Effective PERD . . . . . . . 22

14

What is considered an electrolyte? . . . . 22

15

Questions Answered Correctly >90.0%. . . . 23

1

INTRODUCTION

It is imperative for athletes to rehydrate as
efficiently as possible after strenuous exercise.

Many

athletes participate in multiple practices per day; some of
these practices are spaced within three hours of each
other.

Due to energy demands, the proper rehydration drink

is critical when athletes need to recover for another
session.

There has been a plethora of research done in

recent years, which aim to test the efficiency of recovery
utilizing many types of drinks.

Since the creation of

fluid replacement drinks, they have been the standard for
all athletes; however, the post-exercise rehydration market
is burgeoning. Currently, post-exercise rehydration drinks
include: carbohydrate-electrolyte replacement drinks (fluid
replacement), carbohydrate-protein replacement, milk, and
even pickle juice. Before attempting to evaluate athlete
knowledge concerning these drinks, it is important to
establish a base of knowledge from which clinicians can
draw answers.
Due to their inclusion in every study of rehydration
drinks, it can be concluded that fluid replacement drinks
are among the first choices of rehydration drinks.

Fluid-

2
replacement drinks typically consist of: 0g fat, 0g
protein, 15g carbohydrate, 115mg sodium, and 31mg
potassium.1,2
The electrolytes contained in fluid replacement drinks
have led to it being called a better post-exercise
rehydration drink than plain water.1 As a result, many
companies have created rehydration drinks (ie. Gatorade,
Powerade, Vitamin Water, FRS, etc…). Most drinks, however,
contain a near identical chemical make-up. As a result,
preferences for taste and school affiliation will often
determine what is consumed. Recently, fluid replacement
drink companies have churned out new “additive” products
for their drinks. These are packets of nutrient powders
that can be added to any drink. Used in climates of intense
heat, these are becoming more commonplace as they gain
widespread acceptance. The electrolytes often added are
Sodium, Potassium, Calcium, and Magnesium. The theory
behind these new additives is that simple fluid replacement
drinks may not always be enough to fulfill hydration needs.
Due to athletic demands, new rehydration drinks are
always being produced.

One newer type of drink is a

carbohydrate-protein drink.

These drinks have a very

different nutrient makeup than fluid-replacement drinks: 4g
protein, 1g fat, 16g carbohydrate, 127mg sodium, and 16mg

3
potassium per serving. However, clinical trials have shown
no increased effects (muscle protein synthesis, strength
gains, cycle time to exhaustion, etc…) over fluidreplacement drinks.2 The ideology behind infusing protein
into these drinks is to increase muscle recovery after
exercise. The typical protein type found in these drinks is
whey protein. Support for this theory has been provided by
research.3 In one clinical trial, weight-lifters had an
increase in muscle protein uptake at a higher level with
10g whey protein and 21g carbohydrate than a drink with
carbohydrate only. The positive protein balance observed
among the participants in the whey protein group was
hypothesized to lead to greater hypertrophy and, in effect,
strength gains.
Recently, milk has entered the discussion of postexercise rehydration drinks.

The reason for this is that

milk contains all the nutrients thought to be important in
a post-exercise rehydration drink.4 Milk can be processed
and altered in many different ways.

For example, there is

whole milk, 2% milk, skim milk, chocolate milk, strawberry
milk, and soy milk; all of these contain different
nutrients.

In a direct comparison, chocolate 2% milk

appears to show the greatest benefit to athletes.3 The
nutrient makeup of typical chocolate 2% milk is: 8g

4
protein, 5g fat, 27g carbohydrate, 159mg sodium, 446mg
potassium.

However, the reasons for the positive results

have not been thoroughly studied. Common theories
accounting for this include: slower digestion of proteins,
increased circulation of fatty acids within the blood, less
urine production post-exercise, and increased amount of
protein.2-5
While researching post-exercise rehydration drinks, it
is important not to lose sight of the main objective:
general health of the athlete. Athletes need to be educated
on basic nutrition concepts and rehydration drinks so they
may make informed decisions on what they are ingesting.
While numerous studies have examined athlete knowledge
concerning basic nutrition, none have examined knowledge
solely based on rehydration.7-12 Therefore; there is a gap in
knowledge that needs to be explored. Athletes must be
tested on knowledge and usage of post-exercise rehydration
drinks.
This study will attempt to answer the following
questions: 1) What do athletes know about post-exercise
rehydration and 2) Does post-exercise rehydration drink
consumption and knowledge vary between gender and sport?

5

METHODS

The primary purpose of this study is to: review
current literature on post-exercise rehydration drinks,
test athlete knowledge of post exercise rehydration drinks,
and evaluate the usage of post exercise rehydration drinks.
The following section will include the following
subsections:

research design, subjects, instruments,

procedures, hypotheses, and data analysis.

Research Design

This research is a descriptive research design. The
independent variables will be: gender, division of
institute, and sport played. The dependent variables will
be the knowledge score as measured by the number of
questions answered correctly in that section of the survey
and the type of drink used. The knowledge score will be a
numerical value ranging from 0 to 19, 19 being a perfect
score.

6
Subjects

The subjects that will be used for this study will be
volunteer male and female athletes from California
University of Pennsylvania and High Point University. All
athletes 18 years of age and older at these institutions
will be provided the opportunity to participate.

The study

will be approved by the Institutional Review Board at
California University of Pennsylvania (Appendix C1) prior
to any data collection.

The cover letter to the athlete

(Appendix C2) and survey (Appendix C6) will be distributed
electronically.

Each participant’s identity will remain

confidential and will not be included in the study.

Preliminary Research

The survey was created by the primary researcher in
consultation with thesis committee members.

After review

by the committee, a pilot study of the survey was given to
a random group of athletes in order to determine
reliability.

7
Instruments

The survey (Appendix C6) was created and distributed
using Survey Monkey. The survey consisted of demographic
questions and a knowledge assessment section.

Questions

were created using established rehydration protocols from
the American College of Sports Medicine and National
Athletic Trainers’ Association. The survey was broken up
into three sections: demographic information, use of postexercise rehydration, and athlete knowledge. If athletes do
not regularly consume a post-exercise rehydration drink,
defined as a drink consumed within an hour of physical
activity in order to aid in recovery, they will skip the
section dealing with use of post-exercise rehydration
drinks and proceed from demographic information to
knowledge. The knowledge questions were developed by the
researcher. All questions include answers which are backed
by empirical evidence. The questions test knowledge in the
following areas: nutrients in sweat, nutrients considered
electrolytes, types of post-exercise rehydration drinks,
dehydration, and fluid-replacement protocols.

8
Procedure

The athletic director at each institution will be
emailed a cover page outlining the research. They will then
be asked to return a letter of permission to use their
school’s athletes as test subjects. Following approval by
the California University of Pennsylvania’s Institutional
Review Board, the athletic director will be forwarded an
email which will contain a cover letter and link to the
survey, created on www.surveymonkey.com. A follow-up email
will be sent out with four days remaining of data
collection.

Hypotheses

The following hypotheses were based on previous
research and the researcher’s intuition based on a review
of the literature:
Hypothesis 1:

Post-exercise rehydration drink

knowledge will vary significantly based on sport.
Hypothesis 2:

Post-exercise rehydration drink

knowledge will not vary based on gender.
Hypothesis 3: Post-exercise rehydration drink usage
will vary significantly between sports.

9
Hypothesis 4: Post-exercise rehydration drink usage
will differ significantly between genders.

Data Analysis

All data will be analyzed by PASW Statistics 18 for
Windows at an alpha level of 0.05. An ANOVA was used to
test post-exercise rehydration drink knowledge and sport. A
chi-square was used to test: post-exercise rehydration
drink usage and sport, post-exercise rehydration drink
usage and gender. A T-Test was used to test post-exercise
rehydration drink knowledge and gender.

10
RESULTS

The purpose of this study was to review the literature
of post-exercise rehydration drinks and determine athlete
knowledge and use of post-exercise rehydration drinks. The
following section contains the data collected through the
study and is divided into three subsections: Demographic
Information, Hypotheses Testing, and Additional Findings.

Demographic Information

The participants were collegiate athletes at High
Point University (n = 41) and California University of
Pennsylvania (n = 58). Out of the 109 returned surveys, 99
were usable for data collection. Of the 99, there were 29
males and 70 females. The breakdown of respondents for each
sport is indicated in Table 1. Ages of the participants
ranged from 18 to 23 (Table 2).

11
Table 1. Participants per Team
Sport
Frequency
Volleyball
5
Tennis
3
Golf
9
Soccer
20
Swimming
12
Track and Field
33
Cross Country
17
Total
99

Table 2. Age of Participants
Age
Frequency
18
16
19
32
20
25
21
17
22
8
23
1
Total
99

Percentage
5.1
3.0
9.1
20.2
12.1
33.3
17.2
100

Percentage
16.2
32.3
25.3
17.2
8.1
1.00
100.0

Hypothesis Testing

The following hypotheses were tested in this study.
All hypotheses were tested with a level of significance set
at α ≤ 0.05. An ANOVA was used to test for differences
between post-exercise rehydration drink knowledge and
sport. A chi-square was used to test for a relationship
between post-exercise rehydration drink usage and sport as
well as post-exercise rehydration drink usage and gender. A
T-test was used to test for a significant difference in

12
post-exercise rehydration drink knowledge depending upon
gender.
Hypothesis 1:

Post-exercise rehydration drink

knowledge will vary significantly based on sport.
Conclusion: A one-way ANOVA was used to compare
knowledge score means and sport, no significant difference
was found (F(6,92) = 1.934, p > .05), shown below in Table
3.The overall mean score for all participants was MEAN
(SD).

Table 3. One-Way ANOVA between Knowledge Score and Sport
Played
Variables
Sum of
df
Mean
F
P
Squares
Square
Between Groups 47.568
6
7.928
1.934
.084
Within Groups
377.180
92
4.100
Total
424.747
98

Hypothesis 2:

Post-exercise rehydration drink

knowledge will not vary based on gender.
Conclusion: Findings supported the hypothesis as no
significance difference between drink knowledge and gender.
An independent-samples T-test was calculated comparing the
mean score on the knowledge based portion of the study and
the gender of the participant. No significant difference
was found (t(29) = .268, p > .05). The mean of the males (m

13
= 14.14, sd = 2.133) was not significantly different from
the mean of the females (m = 14.01, sd = 2.075), as shown
in Table 4.

Table 4. T-Test between Drink Knowledge and Gender
Gender
N
Mean
Standard
Standard t
P
Deviation
Error
Mean
Male
29
14.14
2.133
.396
.268 .790
Female
70
14.01
2.075
.248

Hypothesis 3: Post-exercise rehydration drink usage
will vary significantly between sports.
Conclusion: Participants usage of post-exercise
rehydration drinks by sport can be found in Table 10.

A

chi-square test of independence was calculated comparing
post-exercise rehydration drink usage and sport played; no
significant relationship was found (X2(6) = 7.786, p >.05),
as shown in Table 5.

Table 5. Chi-square Comparison of PERD Usage and Sport
Variable
N
df
Chi-square value
Sig
Sport and PERD
99
6
7.786
.254
Usage

Hypothesis 4: Post-exercise rehydration drink usage

14
will differ significantly between genders.
Conclusion: Rehydration drink usage by gender can be
found in Table 6. Findings did not support the hypothesis
as no significance difference between drink knowledge and
gender. A chi-square test of independence was calculated
comparing gender and PERD use, (X2(1) = .357, p >.05), as
shown in Table 6.

Table 6. Chi-Square Comparing PERD Usage and Gender
Variable
N
df
Chi-square value
Gender and PERD
99
1
.357
Usage

Sig
.567

15
Additional Findings

Additional tests were conducted to determine PERD
usage. Of the 99 surveyed, 82 reported they consumed a
PERD. Usage amount is shown in Table 7.

Table 7. Times Per Week PERD is Consumed
Days Per Week
Frequency
Percentage
1
10
12.2
2
6
7.3
3
19
23.2
4
11
13.4
5
17
20.7
6
19
23.2
Total
82
100.0

When asked what they consumed for a PERD, ten types
were reported, as seen in Table 8. The most commonly used
drink was water, followed by Gatorade and chocolate milk

Table 8. Types of PERDs Used
Type
Frequency
Gatorade
37
Powerade
20
Accelerade
1
Muscle Milk
8
Chocolate Milk
36
Water
61
Propel
1
Protein Shake
2
GENr8
1

16
It is interesting to note water came in as the number
one drink when it is not considered a PERD. This will be
discussed in the discussion section. The responses can be
divided into four categories, as shown in Table 9.

Table 9. Post-Exercise Rehydration Drink Category
Type
Frequency
Fluid-replacement
58
Carbohydrate-protein
12
Water
61
Milk
36
Total
167

17

DISCUSSION

The purpose of this study was to determine athlete
knowledge and use of post-exercise rehydration drinks. It
is hoped that these findings will help guide athletic
trainers as they provide nutritional counseling and advice
to their patients.

The following section is divided into

three subsections: Discussion of Results, Conclusions, and
Recommendations.

Discussion of Results

The primary purpose of this study was two-pronged: to
evaluate the effect of several factors on athlete knowledge
of post-exercise rehydration drinks and to determine if
athletes consumed a post-exercise rehydration drink.
Based on the review of literature, the researcher
concluded that usage would differ between sports; however,
no significance difference in PERD usage was found between
sports. This could be due to a number of factors. A
possibility for the findings could be due to the sports
that returned the survey. The amount of PERD usage by team
is shown in Table 10.

18

Table 10. Post-Exercise Rehydration Use by Team
Team

Number Yes (%)

Number No (%)

Total (%)

Volleyball

5 (100%)

0 (0%)

5 (100.0%)

Tennis

1 (33.3%)

2 (66%.7%)

3 (100.0%)

Golf

8 (88.9%)

1 (11.1%)

9 (100.0%)

Soccer

16 (80.0%)

4 (20.0%)

20 (100.0%)

Swimming

11 (91.7%)

1 (8.3%)

12 (100.0%)

Track & Field

28 (84.8%)

5 (15.2%)

33 (100.0%)

Cross Country

13 (76.5%)

4 (23.5%)

17 (100.0%)

Total

82 (82.8%)

17 (17.2%)

99 (100.0%)

As the table shows, volleyball reported the highest
amount of PERD usage, 100.0%, while tennis reported the
lowest, 33.3%. The results show a trend toward using PERDs
as all teams except tennis reported higher than 50% usage.
Had there been more respondents in volleyball or tennis,
significant differences may have been found.
While no significant differences were found between
teams and knowledge score, interesting trends were noticed.
The highest individual score was a 19, or perfect,
belonging to a cross country athlete. The lowest score was
a 9 which belonged to both a tennis and swimming athlete.
The lowest overall team score belonged to tennis (m =

19
12.00, sd = 2.648), while the highest was cross country (m
= 15.18, sd = 2.215). Interestingly, the second lowest
score was volleyball (m = 12.80, sd = 2.168) who also
reported the highest amount of PERD usage. While it is
important to note the two lowest scores also had the lowest
responses, it can be inferred that PERD usage is not
dependent on knowledge.
The researcher also hypothesized that usage would
differ between gender. Rationale for this was based on
prior research which indicated males used protein drinks
and other muscle enhancing products more than females.8,13,14
While both studies found dietary supplement use to be
similar, it was thought that only protein drink use would
be a strong predictor for PERD use.
Research has found significant differences in
knowledge between genders when testing overall nutritional
knowledge.9 In the study, females scored higher on areas
dealing with vitamins, minerals, and health related
disorders. When it came to protein and carbohydrates for
strength gains, however, males scored higher than females.
As a result the researcher hypothesized that nutritional
knowledge would not have significant difference between
genders. Support for this was found as there was no
significant difference. Interestingly, males scored higher

20
(though not significantly) than females, (m = 14.14, sd =
2.133) and (m = 14.01, sd = 2.075), respectively. These
findings are not consistent with other research.9,11 Reasons
for this could be due to this survey only looking at PERD
knowledge and not overall health knowledge.
To this researcher’s knowledge, post-exercise
rehydration drink knowledge has not been studied across
multiple sports. When hypothesizing that PERD knowledge
would have significant difference between sports, studies
using general nutrition knowledge was used.9 Support for
this argument was not found as there were no significant
differences between sport played and knowledge score.
Possible explanations for this are: the sports who returned
surveys were not varied enough (all focusing on aerobic
exercises rather than anaerobic activity) or that
nutritional knowledge does not translate well to PERD
knowledge.
While team means for knowledge score were all above
50%, some questions were answered incorrectly more than 50%
of the time. The question answered correctly the least was
question 7. Question 7 asked, “At what percent body weight
loss does dehydration START to impact performance, A) 1-2%
B) 3-4%, C) 5-6%, D) 7-8%, E) Greater than 8%”? The correct

21
answer, 1-2%, was selected 30.3% of the time, as shown in
Table 11.
Table 11. Dehydration’s Impact on Performance
Choice
Frequency
Percentage
1-2%
30
30.3
3-4%
33
33.3
5-6%
18
18.2
7-8%
13
13.1
>8%
5
5.1
Total
99
100.0

It is unclear why the second choice, 3-4%, was
selected more often than the correct choice, 1-2%.
Another question participants scored poorly on was
question 13. Question 13 asked, “Which of these does NOT
dehydrate you faster than normal, A) Caffeine B) Alcohol C)
Ephedra D) Sugar”? The correct answer, sugar, was selected
only 39.4%, as seen Table 12.

Table 12. Which of these does NOT dehydrate you faster?
Choice
Frequency
Percentage
Caffeine
6
6.1
Alcohol
7
7.1
Ephedra
47
47.5
Sugar
39
39.4
Total
99
100.0

These results are interesting in that they show a lack
of nutritional knowledge among athletes. A reason for this
could be due to the negative press ephedra has garnered. It

22
is possible that athletes assumed ephedra was the answer
because it is illegal in sports. Whatever the reason, it
shows a lack of knowledge by the participants.
When asked if water was an effective PERD,
participants reported it was at a rate of 67.7%, as shown
in Table 13.

Table 13. Water is NOT an Effective PERD.
Answer
Frequency
Percentage
True
20
20.2
False
67
67.7
I don’t know
12
12.1
Total
82
100.0

Recently, it has been reported that water alone is not
enough for athletes to get back into positive fluid balance
and may lead to further dehydration by decreasing blood
osmolality.1,16,17
Participants also had trouble selecting the correct
electrolyte out of four possibilities, as shown in Table
14.
Table 14. What is considered an electrolyte?
Nutrient
Frequency
Percentage
Calcium
40
40.4
Hydrogen
24
24.2
Oxygen
13
13.1
Lithium
22
22.2
Total
99
100.0

23
The correct answer, calcium, was answered correctly
just 40.4% of the time (n = 40). This shows a lack in both
general nutrition and PERD knowledge.
While the aforementioned questions showed a lack of
PERD knowledge, there were some which were answered
correctly almost universally. Only one question was
answered correctly 100.0% of the time, question 14.
Question 14 was, “If I am not thirsty, I shouldn’t drink
anything, A) True, B) False, C) I don’t know”. All
participants answered false. This is an important finding
as it shows the athlete’s awareness of needing to regularly
consume fluids while exercising. Four other questions
yielded a correct response rate greater than 90.0%,
questions 4, 5, 10 and 12, shown in Table 15.

Table 15. Questions
Question
Question 4
Question 5
Question 10
Question 12

Answered Correctly >90.0%
Frequency of Yes
Percentage of Yes
94
94.9
96
97.0
97
98.0
98
99.0

a.

Question 4, “Which of these is NOT a symptom of heat illness?”

b.

Question 5, “When should a PERD drink be consumed after exercise?”

c.

Question 10, What determines if a drink is a good PERD?”

d.

Question 12, “Everyone sweats at the same rate.”

24
Conclusions

While certain questions showed a lack in athlete
knowledge concerning PERDs, it was encouraging to see all
teams and gender scoring above 50%, in fact, the lowest
team score was a 63% (Tennis) while the highest was an 80%
(Cross country). This study did not find significant
differences between knowledge and gender or knowledge and
sport. Furthermore, no significant differences were found
between PERD use and gender or PERD use and sport played.
This research is important for athletic trainers
specifically for a number of reasons. With the high
percentage of athletes using PERDs, it is important for
athletic trainers to keep up-to-date on PERD information.
Athletic trainers see athletes more than dieticians,
doctors, and most other medical professionals. Therefore,
they are in the optimal position to educate athletes as to
their needs and the effect PERDs can have. This provides an
opportunity to be the focal point toward helping athletes
stay hydrated, reducing the risk of heat illness. Athletic
trainers are also at most, if not all, practices for their
assigned sports. This is most important during the summer
when the heat index climbs and athletes are at a greater
risk for heat illness. Athletic trainers up-to-date with

25
current PRED research will be able to better serve their
athletes as to what to drink, when to drink, and why to
drink, possibly saving lives every year.
Also of note, particularly for an athletic trainer is
that many athletes considered water to be an effective
PERD. With this logic, if athletic trainers are not
conscientious, athletes may be drinking only water while
exercising in hot climates. This causes a problem due to
water lowering sodium levels in the body, causing more harm
than good.17 Athletes need to know: what they should be
drinking, the proper amount to drink and the right time to
drink the rehydration drink. As mentioned, athletic
trainers are in the best position to help athletes with
these decisions.
This study provides a basis for which other research
can draw upon. The results of this research are a benefit
to the medical community in that it shows athletes are
consuming PERDs at a high rate, (82%). However, the data
also shows that athletes consider water to be an effective
PERD; as more evidence points to the contrary, it is
important to make sure the athletes know this.

26
Recommendations

While athletes continue to consume PERDs, more
research should be performed to discern what is the optimal
PERD as well as how to pass that knowledge onto the
athletes. One possibility to help in this effort would be a
study comparing the effectiveness of the top five PERDs
used by athletes today on anaerobic and aerobic capacity.
Athletes could be divided up into two groups, aerobic or
anaerobic based activities. Those groups can then have subgroups of: control, fluid-replacement, carbohydrate-protein
replacement, 2% chocolate milk. A 12-week clinical study
could then be undertaken to ascertain which drink provides
the most benefit for each group of athletes.
This study showed that while athletes have a general
sense of PERDs, their knowledge is still limited. A study
should be conducted to assess the optimal way to distribute
information to athletes. A pre-test survey could be
administered to a group of athletes. After which, they
could be put into one of several groups that distribute
knowledge a different way (brochure, meeting, podcast,
etc…). A month later, a post-test would be administered to
see which group scores better post-test.

27
REFERENCES

1.

Casa D, Hillman S. National Athletic Trainers'
Association Position Statement: Fluid Replacement for
Athletes. J Athl Training. April 2000;35(2):212.

2.

Watson P, Love T, Maughan R, Shirreffs S. A comparison
of the effects of milk and a carbohydrate-electrolyte
drink on the restoration of fluid balance and exercise
capacity in a hot, humid environment. Eur J Appl
Physiol. November 2008;104(4):633-642.

3.

Roy BD. Milk: the new sports drink? a review. J Int
Soc Sports Nutr. 2008 Oct 2;5:15.

4.

Karp J, Johnston J, Tecklenburg S, Mickleborough T,
Fly A, Stager J. Chocolate Milk as a Post-Exercise
Recovery Aid. Int J Sports Nutr. February
2006;16(1):78-91.

5.

Tang J, Manolakos J, Kujbida G, Lysecki P, Moore D,
Phillips S. Minimal whey protein with carbohydrate
stimulates muscle protein synthesis following
resistance exercise in trained young men. Appl Physiol
Nutr Metab. December 2007;32(6):1132-1138.

6.

Shirreffs S, Casa D, Carter R. Fluid needs for
training and competition in athletics. J of Sports
Sci. December 2, 2007;25:83-91.

7.

Hartman JW, Tang JE, Wilkinson SB, Tarnopolsky MA,
Lawrence RL, Fullerton AV Phillips SM. Consumption of
fat-free fluid milk after resistance exercise promotes
greater lean mass accretion than does consumption of
soy or carbohydrate in young, novice, male
weightlifters. Am J Clin Nutr 86: 373–381, 2007.

8.

Jackson J, Lyons T, Roberts J, Geary C, Williams J.
Use of Nutritional Supplementation Among University
Recreation Users. Rec Sports J. April 2010;34(1):2-8.

9.

Dunn D, Turner L, Denny G. Nutrition Knowledge and
Attitudes of College Athletes. Sport Journal. October
2007;10(4):45-52.

28
10.

Kunkel M, Bell L, Luccia B. Peer nutrition education
program to improve nutrition knowledge of female
collegiate athletes. J Nutr Educ. March
2001;33(2):114-115.

11.

Jessri M, Jessri M, RashidKhani B, Zinn C. Evaluation
of Iranian College Athletes' Sport Nutrition
Knowledge. Int J Sport Nutr. June 2010;20(3):257-263.

12.

Abood D, Black D, Birnbaum R. Nutrition Education
Intervention for College Female Athletes. J Nutr Educ.
May 2004;36(3):135-139.

13.

Braun H, Koehler K, Geyer H, Kleinert J, Mester J,
Schänzer W. Dietary Supplement Use Among Elite Young
German Athletes. Int J Sport Nutr. February
2009;19(1):97-109.

14.

Froiland K, Koszewski W, Hingst J, Kopecky L.
Nutritional supplement use among college athletes and
their sources of information Int J Sport Nutr.
February 2004;14(1):104-120.

15.

Coso J, Estevez E, Baquero R, Mora-Rodriguez R.
Anaerobic performance when rehydrating with water or
commercially available sports drinks during prolonged
exercise in the heat. Appl Physiol Nutr Metab. April
2008;33(2):290-298.

16.

Costill D. Carbohydrate for athletic training and
performance. Boletín De La Asociación Médica De Puerto
Rico. August 1991;83(8):350-353.

17.

Merson S, Maughan R, Shirreffs S. Rehydration with
drinks differing in sodium concentration and recovery
from moderate exercise-induced hypohydration in
man. Eur J Appl Physiol. July 2008;103(5):585-594.

29

APPENDICES

30

APPENDIX A
Review of Literature

31
REVIEW OF LITERATURE
Athletes lose more than just water when they sweat
while working out. Therefore, it is imperative for them to
replenish with more than simply water after working out.
The choice of what to drink post-exercise can have profound
effects on an athlete’s well-being and ability to perform
later in the day. With all the conflicting messages about
rehydration drinks, athletes can make drink choices on
partial or false information. As a result, athletes may be
under-performing. Also, many athletes participate in
multiple practices per day; some of these practices are
spaced within mere hours of each other.

Due to energy

demands, proper rehydration is critical when athletes need
to recover for another session, and often, water alone is
not enough.1,2 There has been a plethora of research done in
recent years which aims to test the efficiency of recovery
in many types of drinks.

1-14

This literature review aims to explain the benefits of
various drinks and why some may be better than others.

The

topics for this literature review will be discussed in the
following sections:

why a post-exercise rehydration drink

is needed, nutritional demands of athletes, current

32
rehydration drinks on the market, and athlete knowledge of
post-exercise rehydration drinks.

Benefits of Post-exercise Rehydration Drinks

Sweating is a natural body function in response to the
increase in core temperature that accompanies exercise.
Athletes are no exception; quite the contrary, they sweat
more than the average person15,16. As such, they must off-set
this loss of water and nutrients utilized by exercise by
taking in more than the average person17. This sweat loss
can lead to heat illness and dehydration18,19. Therein lies
the need for a post-exercise rehydration drink. Athletes
need a post-exercise rehydration drink in order to: prevent
dehydration, get back the nutrients they lose in sweat,
return to positive fluid balance, and perform to their
optimal capacity.

Dehydration
Dehydration is a rampant problem plaguing athletes,
especially during double sessions in late summer. There are
two (2) types of dehydration: exercise-induced dehydration
(dehydration brought on by exercise) and hypohydration
(dehydration before exercising).

20

It has been reported

33
that athlete performance is negatively affected when they
lose ~2% body mass due to perspiration

19, 20, 3, 8, 21, 22, 13, 23,

14, 24, 25

. Dehydration is defined as: a urine specific gravity

of >1.02018,

19

. Dehydration can be combated with proper pre-

hydration; however, during multiple bouts of exercise per
day, practices start early and, as a result, it may not
always be feasible to properly pre-hydrate. As a result,
athletes must rehydrate after exercise. This need
exponentially increases when another bout of exercise is to
follow in a short time. Athletes are suggested to consume
enough fluid as to ensure not more than 2% body mass is
lost

18, 19

. It has been reported that properly rehydrating

is possible without the use of a post-exercise rehydration
drink for athletes who do not have another session of
exercise within 12 hours because that athlete will be back
in positive fluid balance after eating regular meals.23
However, for those with another bout in the same day, this
is not the case. Starting a session of exercise dehydrated
and negative fluid balance leads to an outset of decreased
performance in addition to making the dehydration worse26.
Furthermore, the more dehydrated an athlete gets, the more
their performance decreases.27

34
Starting Exercise Hypohydrated
It has been reported that up to 66% of athletes appear
hypohydrated at the outset of exercise.2 Hypohydration can
have a significant impact on exercise capability. Some of
these factors are: increase heart rate, increase blood
pressure, and core temperature.28-29 The ability of athletes
to return to positive fluid balance between multiple
exercise periods is critical to maintaining a high
intensity of activity during a second session.

As a

result, finding the right post-exercise rehydration drink
is mandatory for proper care of athletes. Furthermore,
research indicates that additional strain is put on the
cardiovascular system to maintain exercise ability while
hypohydrated.42

Returning to Fluid Balance
In a study to determine the effectiveness of multiple
post-exercise rehydration drinks on returning athletes to
positive fluid balance was comprised of seven physically
active males who completed a max VO2 test, familiarization
test, and two experimental tests.

Sweat was collected from

the athletes and measured for electrolyte content. The
first experimental test ended when participants lost 1.8%
body mass. The participants were given 30 minutes rest

35
before drinking the selected beverage (1% milk or fluidreplacement drink) in an amount that was 150% their sweat
loss.

After three hours of rest, the participant’s fluid

levels were measured and then put through a second test to
test time to exhaustion. At the end of the three hour
recovery it was found that the athletes ingesting the
carbohydrate-electrolyte drink were euhydrated (neutral
fluid balance) while the patients consuming milk were in
positive fluid balance when compared to water alone.3,21,22,30
This is an important study because it could help in
providing a basis for post-exercise drink volume. However,
without being in a laboratory setting, knowing the amount
of sweat loss MAY prove difficult.

Nutritional Needs of Athletes

Nutritional needs of athletes are far greater than
those of the general population. Athlete must consume more
fat, carbohydrates, proteins, vitamins, and minerals than
typical guidelines stipulate.17 A general population diet
consists of: 45-55% carbohydrate (or 3-5 grams/kg/day, 1015% protein, and 25-35% fat.18 For carbohydrate
recommendations, athletes involved on high volume of
exercise, defined as 2-3 hours per day, 5-6 times per week,

36
have a diet that should consist of: 55-65% carbohydrate (58 grams/kg/day).18 These levels of carbohydrates should be
sufficient to restore muscle and liver glycogen stores. For
protein, needs of athletes increase from .8-1.0 kg/body
weight/day to 1.5-2.0 kg/body weight/day.17 The additional
nutrient needs of athletes extends to hydration as well.

Nutrients in Sweat
As athletes sweat, they lose valuable electrolytes
along with water. The most important nutrients to exercise
hydration are Sodium (Na+), Potassium (K+), and Chloride
(Cl-).16,

22

These electrolytes must also be supplemented with

water while rehydrating. Along with the previously
mentioned electrolytes, Calcium (Ca2+), Magnesium (Mg2+), and
Iron (Fe) are also lost in sweat.22 Sodium is of most
importance as it has been show to impact exercise capacity
along with dehydration.1
Current research indicates that sweat rates are
correlated with body mass, sport, and environmental
conditions.16 It is important to note the differences when
forming hydration protocols and strategies for athletes.22

37
Current Post-Exercise Rehydration Drinks

The market for post-exercise rehydration drinks is
ever-expanding. New companies and new products are
constantly entering the field of post-exercise rehydration
drinks.

Fluid-Replacement Drinks
The use of fluid replacement drinks has become
commonplace due to the relationship between fatigue and
carbohydrate availability.3

Fluid replacement drinks appear

in commercials, magazines, on billboards, and sponsor
athletic events. As a result, it may be concluded that
fluid replacement drinks are the most popular form of postexercise rehydration drinks.

Fluid-replacement drinks

typically consist of: 0g fat and protein, 15g carbohydrate,
115mg sodium, and 31mg potassium.11

The electrolytes

contained in fluid replacement drinks have led to it being
called a better post-exercise rehydration drink than plain
water.18 As a result, many companies have created their own
drinks to compete in the market. Most, however, are nearly
identical in terms of nutrient make-up. This makes taste
preference and school affiliation the determining factor in
what is consumed. Recently, fluid replacement drink

38
companies have churned out new “additive” products for
their drinks. These are packets of nutrient powders that
can be added to any drink. The electrolytes often added are
Sodium, Potassium, Calcium, and Magnesium.

Carbohydrate-Protein Drinks
Due to athlete demands, new rehydration drinks are
always being produced.

One newer type of drink is a

carbohydrate-protein drink.

These drinks have a very

different nutrient makeup than fluid-replacement drinks: 4g
protein, 1g fat, 16g carbohydrate, 127mg sodium, and 16mg
potassium. However, clinical trials have shown no increased
effects over fluid-replacement dinks.4 The ideology behind
infusing protein into these drinks is to increase muscle
recovery after exercise. The typical protein type found in
these drinks is whey protein. Support for this theory was
provided in a study of weight-lifters. The study found an
increase in muscle protein uptake at a higher level with
10g whey protein and 21g carbohydrate when compared to
carbohydrate only.12 The addition of protein hypothesized to
lead to greater hypertrophy and, in effect, strength gains.

39
Milk
Recently, milk has entered the discussion of postexercise rehydration drinks.

Milk is nutrient dense in all

areas athletes demand.8 Milk can be processed and altered in
many different ways.

For example, there is whole milk, 2%,

skim, chocolate, and strawberry; all of these contain
different nutrients.

In a direct comparison, chocolate 2%

milk appears to show the greatest benefit to athletes due
to its nutrient makeup: 8g protein, 5g fat, 27g
carbohydrate, 159mg sodium, 446mg potassium.

However, the

reasons for the positive results have not been thoroughly
studied.

Common theories accounting for this include:

slower digestion of proteins, increased circulation of
fatty acids within the blood, less urine production postexercise, and increased amount of protein.3,4,11,31

Research Trials of Current Rehydration Drinks
Clinical trials were performed to test time to
exhaustion, fat-free soft tissue mass, fluid balance, and
nutrient balance.

Among these trials, milk performed on

par or better than leading fluid-replacement drinks as well
as carbohydrate-protein drinks.

On average, milk and

fluid-replacement drinks performed equally on time to
exhaustion tests.

Milk performed the best among fat-free

40
soft tissue mass increase, fluid balance, and nutrient
balance. Because of the recent success, imitators are
trying to recreate the nutrients found in milk. However, a
key component taken out is lactose. The reason for this
subtraction is to allow these beverages to be consumed by
even those who are lactose intolerant.
A study to determine milk’s effectiveness on lean mass
tissue gains from progressive resistive exercise was
undertaken. In this study, 56 novice weightlifters
participated in a weight-lifting program which lasted 12
weeks and resulted in 20 sessions of: pushing exercises,
pulling exercises, and leg exercises.31 The drinks tested
were: commercially available carbohydrate drink, soy
beverage, and skim milk.

The quantity taken of each was

500mL directly after finishing the workout and 1 hour postexercise.

One repetition max was determined pre-workout

and compared to post-exercise at 12 weeks.

Milk showed

better results in all categories tested, which were: Body
weight, Fat mass, fat- and bone- free mass, and bone
mineral content.

Type II muscle fiber cross-sectional area

gains were significantly higher in milk than both other
drinks while type I muscle fiber was not statistically
different between soy and milk, but both were significantly
higher than the carbohydrate beverage.

Lean mass tissue

41
showed greatest improvement within those who ingested milk.
Also, in 1 repetition maximal leg strength, milk provided
greater gains in leg press, knee extension, and hamstring
curls by a significantly higher margin. The study provided
by Hartman gives support to the effects milk has in
promoting maximal strength and lean mass tissue increases.
Many athletes participate in multiple exercise bouts
per day for part of their season.

As a result, it is hard

for many to become adequately rehydrated before the second
stint of exercise.

Therefore, the ability to perform at an

optimal level decreases.

Due to the strong support in

other areas, milk (1% chocolate milk in this study) was
tested against other leading drinks (carbohydrate-protein
and fluid-replacement) in endurance tests.

The study being

examined, conducted by Karp et al., quantifies endurance as
time to voluntary exhaustion while maintaining a cycling
speed congruent with 70% VO2 max.

This study had nine male

cyclists undergo a glycogen depleting trial consisting of
alternating 2-min periods of high intensity followed by low
intensity work followed 4 hours later by a stint of cycling
at 70% VO2 max until exhaustion.

This protocol was

completed by all nine athletes on 3 occasions which were
spaced a week apart.

After the data was compared, milk was

shown to produce significantly superior numbers in time to

42
exhaustion and total work produced than a leading
carbohydrate-replacement drink. There was no significant
difference in both categories between milk and a fluidreplacement drink.

The amount of work produced by the

cyclists after ingesting the chocolate milk was 57% higher
than after consuming the carbohydrate-replacement drink
while there was a 48% increase in work produced after the
consumption of a fluid-replacement drink when compared to a
carbohydrate-replacement drink.4
Sweat loss rate is important because athletes lose
both water and nutrients. On average, milk can have ten
times the amount of sodium and potassium as fluidreplacement and carbohydrate-replacement drinks,
respectively. In a study comparing five types of milk
(whole, 2%, 1%, skim, and 2% chocolate), two types of
fluid-replacement drinks (Gatorade Thirst Quencher and
Gatorade Endurance), and a carbohydrate-replacement drink
(Accelerade), chocolate milk was shown to hold more
nutrients.11 This nutrient density becomes beneficial for
the athlete due to the ability to replenish nutrients inbetween workouts.
The ways in which milk helps exercise are immense.
However, it is the why which often alludes researchers.
There is no one reason why milk has so many properties

43
conducive to exercise.

Some of the reasons include: fat

content, amino acid type, carbohydrates, and vitamins.

No

other drink compares to milk’s wide range of nutrients.

It

is within this area further research is required to
ascertain the wide range of benefits milk provides.
A possible obstacle in getting athletes to drink milk
is the fear they (the athletes) will gain weight. Other
hydration drinks do not contain the lipid component of
milk. However, it could be this lipid component that makes
milk such a good drink. The lipid composition in milk
ranges from milk to milk depending if it’s whole, skim, or
in-between. However, regardless of type, the main lipid is
saturated fatty acid. Two of these fatty acids are capric
and lauric acid. In clinical research, these two fatty
acids have been shown to inhibit the Cyclooxygenase
enzyme.32 Cyclooxygenase creates prostanoids that aid in the
inflammatory process and cause pain. Therefore, capric and
lauric acid act as Cox I and Cox II inhibitors. This can
delay or even negate minor pains associated with exercise.
Because they (capric and lauric acid) do not have a strong
effect, this pain masking is not deemed detrimental.
Addressing the issue of milk causing an increase in
body fat among athletes, a study was done to examine the
effects of dairy products on weight management33. Their

44
results found that a diet high in calcium increased
lipolysis and led to 26-39% reductions in body weight than
diets with suboptimal calcium intake.

Furthering research

in this realm found significant increases in body weight
loss among diets high in dairy products.33 In a 24-week
study of obese individuals, participants in the control
group (low-calcium diet) lost 6.4% of their body weight
while participants in the high dairy product group lost
10.88%, diets high in calcium but not from dairy reported
an 8% loss. Furthermore, fat loss from the participants
went up by 38% in high calcium diets and 64% in diets high
in dairy. These findings indicate that there are other
nutrients in milk that attribute to fat loss than just
calcium.
Another nutrient milk has that not all sport drinks
have is protein. Recently, companies have mimicked milk’s
ratio of proteins to fats (Muscle Milk). The main types of
proteins in milk are casien (80%) and whey (20%). Whey
protein receives the commercial coverage and has appeared
in many drinks and powders for increase strength gains.
However, casein protein may be just as valuable to the body
as whey protein.
While whey protein is lauded as the most important
type, research has been found that amino acid uptake was

45
only significantly affected when both proteins were
consumed.34 The reasons for these findings were the amino
acid levels found within muscles after a rest period of
four hours. Whey protein led to higher levels of leucine
while casein protein led to higher levels of phenylalanine.
Leucine is an essential amino acid that increases the
synthesis of muscle protein. Phenylalanine is also an
essential acid needed to create proteins in the body.
Milk has many nutrients not found in other drinks.
Some nutrients may not seem important at first glance;
however, after delving further into the physiology of them,
there may be a place in athletics. Two such nutrients are
Folate and B12. Folate, or folic acid, plays a key role in
the metabolism of amino acids.35 As amino acids are the
building blocks for cells, and especially muscles, an
increase folate consumption due to milk may help athletes
recover faster. Vitamin B12 plays an essential role in the
body as it helps with folate metabolism.36 As previously
stated, folate aids in amino acid metabolism, however,
without being metabolized itself, folate can do very little
to help the body. Therefore, vitamin B12 is an essential
component in amino acid metabolism as a result of its
impact on folate.

46
A major worry for athletes, and especially studentathletes, is coming down with a cold or other illness. Due
to the intense strain put on their bodies, and occasionally
the climate they play in, athletes are more susceptible to
illness than the general public. One nutrient responsible
for immune system function is Zinc.37 Milk can commonly have
18-25% of daily requirements of zinc. This is vastly
different from other sport drinks which generally have
none. It can thus be hypothesized that milk will help
athletes stay healthy during their times of intense
exercise.38
The thyroid gland plays a pivotal role in regulating
metabolic rate and growth. To do this, the thyroid gland
needs Iodine to create triiodothyronine and thyroxine.38 If
the thyroid gland has sufficient amount of Iodine, it
functions properly and regulates a healthy metabolic rate.
This is imperative for athletes because a stable metabolism
can increase fat loss and stimulate nutrient absorption.
A common complaint and possible obstacle with milk is
the prevalence of lactose intolerant individuals. Lactose
is a disaccharide formed by galactose and glucose.39 It
plays an essential role in the digestion and absorption of
other sugars. Lactose is not found in every type of milk.
As a result, different types of milk can be experimented

47
with to determine if there is a suitable kind. Furthermore,
with the advances in modern science, lactose can be taken
out of bovine milk and replaced with other sugars. If mass
production of a milk with lactose taken out, it could solve
the problem for lactose intolerant individuals.

Athlete Knowledge

Athlete knowledge of nutrition is an essential
component to their ability to perform optimally. However,
as seen in previous research, their knowledge is inadequate
and often comes from unreliable sources.40-43 Fad diets,
nutritional recommendations on nutrition labels, and most
articles on common literature do not translate to athlete
nutritional needs. This knowledge base needs to be
addressed in order to provide comprehensive care to
athletes. Athletes who perform multiple bouts of exercise
per day are at an increased rate of nutritional deficit.43
These athletes need special recommendations concerning
their nutritional intake. Athletes who perform multiple
bouts per day constitute a wide range of athletic teams,
especially with sports with extensive pre-season work,
including: soccer, football, basketball, baseball. Most of
these sessions occur under conditions of elevated heat.44 As

48
a result, many athletes begin workouts hypohydrated.43,45
Current research into the field of athlete knowledge of
nutrition focuses mostly on general nutrition guidelines
and needs. As such, there is a lack of research work in
athlete knowledge specific to rehydration drinks.

Summary

While there may be an adequate amount of research
examining the effects of hydration, little is known about
what athletes do with this knowledge. Research indicates
that milk may be the optimal rehydration drink, although
not by a margin significant enough to dissuade the use of
any other type of drink. In conclusion, there potentially
is still a gap between what the medical community knows and
what athletes know. In an attempt to help bridge this gap,
this thesis was performed.

49

APPENDIX B
The Problem

50
The Problem

Statement of the Problem
The purpose of this study is to determine athlete
knowledge concerning post-exercise rehydration drinks. This
is important because athletes’ consumption of post-exercise
drinks is on the rise. By evaluating athlete knowledge and
use, recommendations can be made in regards to future
education of athletes. If athletes are educated in postexercise rehydration drinks, they will be able to make
educated decisions when someone else is not around to
facilitate their decision of what to drink. Lastly, it is
beneficial for athletes to know what the best post-exercise
rehydration drink is.

Definition of Terms
The following definitions of terms will be defined for this
study:
1)

Post-exercise Rehydration Drink – A drink consumed

after exercise that is a meant to facilitate rehydration.48
2)

Athlete – A person who is trained or skilled in

exercises, sports, or games requiring physical strength,
agility, or stamina.49

51
3)

Carbohydrate-Protein Drink – A drink consumed after

exercise that contains carbohydrates and protein, usually
in a 4:1 ratio.1
4)

Fluid Replacement Drink/Carbohydrate-Electrolyte Drink

– A drink consumed after exercise that contains
carbohydrates and electrolytes.1
5)

Hypohydration – Dehydration at the onset of physical

activity.5
6)

Euhydration – Neutral fluid-balance.5

Basic Assumptions
The following are basic assumptions of this study:
1)

The subjects will be honest when they complete their

demographic sheets.
2)

The subjects will answer the knowledge questions to

the best of their ability.

Limitations of the Study
The following are basic assumptions of this study:
1)

Only athletes older than 18 were used as participants.

2)

A true sample was not received due to only surveying

two schools.
3)

Low response rate could have skewed the data

52
Significance of the Study
With the recent push by coaches and healthcare
professionals alike to have athletes use post-exercise
rehydration drinks, athlete knowledge is often overlooked.
Rather than handing athletes a specific drink, athletes
should be instructed on proper rehydration drinks. This
way, they can make educated decisions on their own.

53

APPENDIX C
Additional Methods

54

APPENDIX C1
Institutional Review Board –
California University of Pennsylvania

55

56

57

58

59

60

61

62

63

64

65
Institutional Review Board
California University of Pennsylvania
Psychology Department LRC, Room 310
250 University Avenue
California, PA 15419
instreviewboard@cup.edu
instreviewboard@calu.edu
Robert Skwarecki, Ph.D., CCC-SLP,Chair
Mr. Gregoire,

-

-

Please consider this email as official notification that your proposal
titled “Athlete Knowledge of Post Exercise Rehydration Drinks” (Proposal
#10-047) has been approved by the California University of Pennsylvania
Institutional Review Board as submitted, with the following stipulations:
A screening question or statement indicating that participants must be 18
years of age or older must be present in the consent form and/or
questionnaire.
A statement indicating where the results will be housed and maintained
must be added to the consent form.
Once you have made this revision, you may immediately begin data
collection. You do not need to wait for further IRB approval. [At your
earliest convenience, you must forward a copy of the revised consent form
for the Board’s records].

(1)

(2)
(3)
(4)

The effective date of the approval is 02-23-2011 and the expiration date is
02-22-2012. These dates must appear on the consent form .
Please note that Federal Policy requires that you notify the IRB promptly
regarding any of the following:
Any additions or changes in procedures you might wish for your study
(additions or changes must be approved by the IRB before they are
implemented)
Any events that affect the safety or well-being of subjects
Any modifications of your study or other responses that are necessitated
by any events reported in (2).
To continue your research beyond the approval expiration date of 02-222012 you must file additional information to be considered for continuing
review. Please contact instreviewboard@cup.edu
Please notify the Board when data collection is complete.
Regards,
Robert Skwarecki, Ph.D., CCC-SLP, Chair, Institutional Review Board

66

APPENDIX C2
Cover Letter to Participant

67
Dear Participants:
My name is Joshua Gregoire and I am a master’s degree candidate
at California University of Pennsylvania. One of the requirements
for a master’s degree is the completion of a thesis and for this
I am requesting your help. As of late, the beverage industry has
expended numerous funds in the area of post-exercise rehydration
drinks (PERDs for short). Information about various PERDs is on
television, in magazines, and talked about among coaches. I am
conducting this study to find out what you, the athletes, know
about PERDs as well as how frequently you use them. Your
responses will be anonymous, but it is hoped that the results of
this study will be published for the medical community to see, in
an effort to expand upon the research. Your responses will be
housed in a secure location by surveymonkey.com, accessible only
to the researcher. The survey should not take longer than 10
minutes for you to complete. The effective date of the approval
is 02-23-2011 and the expiration date is 02-22-2012.
If you wish to participate in the study, please follow the link
https://www.surveymonkey.com/s/G5TCF97
Thank you,
Joshua Gregoire, ATC, NASM-PES
Graduate Assistant Athletic Trainer
California University of Pennsylvania

68

APPENDIX C3
Cover Letter to Athletic Director

69

70

APPENDIX C4
Response Letter from Athletic Director

71

72

APPENDIX C5
Liaison Letter

73

74

APPENDIX C6
Survey

75

76

77

78

79

80

81

82

83

84

85

86
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ABSTRACT

TITLE:

ATHLETE KNOWLEDGE AND USE OF POST-EXERCISE
REHYDRATION DRINKS

RESEARCHER:

Joshua P. Gregoire

ADVISOR:

Robert Kane, EdD, PT, ATC

DATE:

April 2011

RESEARCH TYPE: Master’s Thesis
CONTEXT:

Current research indicates that athletes use
supplements at a high rate. Literature has
not examined if this trend correlates to
post-exercise rehydration drink knowledge.

OBJECTIVE:

The purpose of this study was to: test
athlete knowledge of post exercise
rehydration drinks and evaluate the usage of
post exercise rehydration drinks. The study
was a descriptive design survey.

SETTING:

The survey was distributed via email and
taken online at the participants’
convenience on www.surveymonkey.com.

PARTICIPANTS:

The convenient sample of 99 athletes out of
a possible 311 took the online survey at
their convenience after being sent a link
and cover letter. The response rate was
31.8%.

INTERVENTIONS: The independent variables used were sport
played and gender of participants. After
obtaining consent from the athletic
director, athletes were sent the survey and
asked to respond at their leisure. At the
end of the survey window, each response was
given a knowledge score based on the number
of questions answered correctly
MAIN OUTCOME:

The dependent variable used was the
knowledge score given based on the number of

92
questions answered correctly on the survey.
PSAW 19.0 for Windows was used for all data
statistics with an alpha level of <.05.
one-way ANOVA was used to compare knowledge
score means and sport. An independentsamples T-test was calculated comparing the
mean score on the knowledge based portion of
the study and the gender of the participant.
A chi-square test of independence was
calculated comparing post-exercise
rehydration drink usage and sport played. A
chi-square test of independence was
calculated comparing gender and PERD use.
RESULTS:

The research found: no significant
differences between athlete knowledge sport
played, (F(6,92) = 1.934, p = .084), no
significant differences found between PERD
knowledge and gender (t(29) = .268, p
=.790), no significant relationship between
PERD usage and sport played (X2(6) = 7.786, p
=.254), and no significant differences
between gender and PERD usage (X2(1) = .357,
p=.567).

CONCLUSIONS:

Of note was the findings of athlete
knowledge based on gender as males scored
higher than did females, but not
significantly better (m = 14.14, sd = 2.133)
and (m = 14.01, sd = 2.075), respectively.
This research indicates that 80% of athletes
use post-exercise rehydration drinks on a
regular basis.