A study into the effect of carbohydrate solutions, ingested before exercise, on hydration levels post performance

7/23/2019 A study into the effect of carbohydrate solutions, ingested before exercise, on hydration levels post performance.

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Andrew Tanner

09199682

Dissertation

A study into the effect of carbohydrate solutions, ingested before exercise, on hydration

levels post performance.

A project submitted in fulfilment of the requirements for the Dissertation module of the

degree of BSc(Hons) Sports Development & Coaching.

School of Sport and Exercise Science

University of Lincoln



Dissertation Word Count: 6,183.

Abstract.

The effects of carbohydrates on performance and osmolality have not been extensively examined

with only one paper out of fifty fitting the carbohydrate, performance and osmolality criteria. A key

piece of research is by Evans, Shirreffs & Maughan (2009). The aim of the study was to investigate

if different solutions of carbohydrates affect performance and hydration. A total of nine exercise

trained games players, three females (Average age: Nineteen years, Six months and Height: 171.6

cm) and six males (Average age: Twenty years, Five months and Height: 180.3 cm) were recruited

in order to investigate the aim of the study. Ethical approval was given by the University of Lincoln

Ethics Committee after which consent and medical forms were completed by each participant

before testing took place. Participants undertook three different test conditions, each condition

representing a different beverage (Placebo, Five percent carbohydrate and Ten carbohydrate

solution). The test conducted was the Yo-Yo intermittent recovery test. Results from the ANOVA

with Repeated Measures test, using a Lower-bound correction, found means score for osmolality

levels in performers are statistically significant. (F(1.00, 8.00) = 0.480, p <0.05). The post hoc test

found significant differences between the placebo and five percent beverage and the placebo and

ten percent beverage. The Five percent had the lowest average osmolality level (524.44 oSmol).

The results also showed that the Ten percent beverage was most effective at increasing

performance with the average Yo-Yo result being level twenty seven. A key discussion point is the

inability to control beverage consumption of participants before testing which would affect

osmolality results collected. For future research, an overnight or pre testing fast should be put in

place to control the state of hydration with all performers before the testing takes place. The

benefits of this study for games players is that the upper carbohydrate solution boundary has been

found. Any solution equal to or higher than ten percent will not be effective in maintaining

osmolality levels; and although performance is improved with this solution, hydration is not

maintained.



Andrew Tanner Page | I

09199682 Dissertation

Acknowledgments.

I would like to thank my dissertation tutor Mistrelle Baker for all the help and guidance over

the past year with this study.

I would also like to thank the Lincoln University Netball team members and Lincoln

University Sunday five a side team members for help with the testing needed for the study.



Andrew Tanner Page | II


Contents

1.0 Introduction. ........................................................................................................................ 11.1 Background to problem. .................................................................................................. 1

1.2 Key research. .................................................................................................................... 2

1.3 Aim of Study. .................................................................................................................... 4

1.4 Statement of hypotheses. ................................................................................................ 4

2.0 - Literature review. ............................................................................................................... 5

2.1 Introduction. .................................................................................................................... 5

2.2 Games based performance test. ..................................................................................... 7

2.3 Carbohydrates before exercise. ....................................................................................... 8

2.4 Stereotypical hydration beverages vs carbohydrate beverages. ..................................... 9

2.5 Effect of Carbohydrates on Performance. ..................................................................... 11

2.6 Concentration of carbohydrate beverages and effects on osmolality levels. ............... 13

3.0 Methodology. ..................................................................................................................... 16

3.1 Subjects. ......................................................................................................................... 16

3.2 Apparatus. ...................................................................................................................... 16

3.3 Test Procedure. .............................................................................................................. 16

3.4 Statistical analysis. ......................................................................................................... 18

3.5 Drinks justification. ........................................................................................................ 19

4.0 Results. ............................................................................................................................... 20

4.1 Normality checks. ........................................................................................................... 20

4.2 ANOVA repeated measures tests................................................................................... 22

4.3 Post Hoc Test. ................................................................................................................. 24

4.4 Yo-Yo scores for each drink. ........................................................................................... 25

5.0 Discussion. .......................................................................................................................... 275.1 Statement of main findings. ........................................................................................... 27

5.2 Support and comparison for osmolality findings. .......................................................... 29

5.3 Support and comparison for performance in Yo-Yo test. .............................................. 30

5.4 Limitations and recommendations for future research. ................................................ 31

5.5 Conclusion. ..................................................................................................................... 33

6.0 Reference list. .................................................................................................................... 34



Andrew Tanner Page | III


7.0 Appendices. ........................................................................................................................ 38

7.1 Appendix A. .................................................................................................................... 38

7.2 Appendix B. .................................................................................................................... 39

7.3 Appendix C. .................................................................................................................... 40



Andrew Tanner Page | IV


List of tables

Table 1: Hydration Pre and Post performance after conducting the Yo-Yo test.. ..................... 7

Table 2: Breakdown of researchers, timings and outcome of exercise. .................................... 8

Table 3: The composition of selected UK based sports drinks and other beverages.

Carbohydrate content is taken from drink labels.. .................................................................. 13

Table 4: Tests of normality on the Placebo beverage. ............................................................. 20

Table 5: Tests of normality on the Five percent beverage. ..................................................... 20

Table 6: Tests of normality on the Ten percent beverage. ...................................................... 20

Table 7: Comparison of Mean and Standard Deviation figures between the variation of

drinks. ....................................................................................................................................... 22

Table 8: Results from ANOVA test. .......................................................................................... 22

Table 9: Post Hoc Test results. ................................................................................................. 24

Table 10: Box plot showing results of Yo-Yo test for Placebo beverage.................................. 25

Table 11: Box plot showing results of Yo-Yo test for five percent carbohydrate beverage. ... 25

Table 12: Box plot showing results of Yo-Yo test for ten percent carbohydrate beverage. .... 26



Andrew Tanner Page | 1


1.0 Introduction.

1.1 Background to problem.

Over four and a half million people aged fourteen to twenty five years play sport once a

week (Sport England, 2014). Whilst training and competing in different competitive sports at

around the age of fourteen, severe dehydration used to occur. This went on to be a problem

for the team as a whole. When playing team sports, a drink the team typically would

consume at half time to overcome this dehydration was orange juice and water. This

stereotypical drink formed the basis of a carbohydrate solution idea, to be explored further,

focusing more on how a specific solution of carbohydrate drink can be consumed to

overcome the effects of exercise like dehydration. The other part of the problem comes from

the rising price of carbohydrate drinks. Due to the price of consumables across the country

increasing and sport drinks being one of the most popular beverages, prices have soared in

recent years. From 2011 to 2012, the sport drinks market sales slowed from eight percent to

just three percent due to these rise in prices (King, 2013). This rise has lead to participants

creating their own hydration drinks at home from carbohydrate powders. A example of this

is Maltodextrin carbohydrate powder. These can be brought online for a smaller fee than a

bulk buy of sports drinks, indicating a cheaper way of maintaining hydration. The study is

interested in finding the optimum solution to maintain hydration, but also increase

performance.





1.2 Key research.

Goedecke et al (2013) conducted research into the effect of consuming a seven percent or a

placebo beverage before exercise on football players' performance. Time to fatigue was

found to be extended when consuming this seven percent carbohydrate beverage. Another

beverage with an eight percent solution was found to increase running performance when

consumed before exercise (Ingle, Cooke & King, 2011). This increase in performance was also

found with a ten percent beverage in a study by Gomes et al (2013), where consuming a ten

percent beverage resulted in a increase in performance when undertaking intermittent

sports.

These studies all show the effect that carbohydrates have on performance. Three different

solutions are mentioned within the studies, which all show an increase in performance or

time to fatigue. This tells us that there are a range of carbohydrate solutions available which

all have different effects on performance when exercising.

Shirreffs (2009) studied the effects of a six and seven percent carbohydrate beverage. The

findings showed that both a six and seven percent carbohydrate beverage is effective in

reducing osmolality levels (280-289 mOsmol/kg) compared to drinks which contained a

carbohydrate solution of above ten percent (660 - 700 oSmol/kg).

Although this study shows the effects of osmolality on performance, there is a lack of

research into the effect of carbohydrate beverages on performance and osmolality levels.

When performing a quick review of papers containing the words "Performance and

osmolality and carbohydrate", one paper out of the first fifty matched the osmolality criteria.

This paper is by Evans, Shirreffs & Maughan (2009) into "Post exercise Rehydration In Man:

The Effects Of Carbohydrate Content And Osmolality Of Drinks". The paper is further





explained in section two point six. Out of the top fifty results, a further twenty two papers

featured the words "hydration" and "recovery" in the title.





1.3 Aim of Study.

The aim of the study is to Investigate if different solutions of carbohydrates affect

performance and hydration.

1.4 Statement of hypotheses.

Research Hypothesis H1: There will be a significant difference in osmolality recorded

between each drink trial.

Null Hypothesis H0: There will be no significant difference in osmolality recorded between

each trial.

Research Hypothesis H2: There will be a significant difference in Yo-Yo performance level

between placebo drink and carbohydrate drinks.

Null Hypothesis H0: There will be no significant difference in Yo-Yo performance level

between placebo drink and carbohydrate beverages.





2.0 - Literature review.

Appropriate fluid intake is important in all performance, as a reduction in fluid can lead to

severe dehydration, muscle cramps and fainting (Quinn, 2011). There are three main types of

sports drinks available to performers. Firstly, an isotonic beverage which "Quickly replaces

fluids lost by sweating and supplies a boost of carbohydrates; made for the average athlete".

Secondly a hypotonic beverage which "quickly replaces fluid lost, and is best for low-

perspiration athletes such as jockeys and gymnasts". Finally a hypertonic beverage which

supplements daily carbohydrate intake after exercise to top up current glycogen stores. This

drink is used primarily for athletes such as long distance runners who need the extra

carbohydrates and electrolytes. (Health and Safety, 2010)

2.1 Introduction.

Over the past five years, the notion of sports drinks and the effect on hydration has become

a well researched part of sports performance. A study by Phillips et al (2011) explored the

current body of research available in the area of hydration and the effects on team games.

He found thirty five papers in total relating to this. Only papers which presented findings of

carbohydrate ingestion immediately prior to and during laboratory or field exercise of team

games were used. Specifically, a total of twenty five papers were found relating to mental

function and skill performance. A further thirty six papers were found relating to the

influence of carbohydrates on team games, exercise performance and capacity. The findings

of Phillips et al (2011) into optimum carbohydrate solutions recommends between a five and

seven percent solution for team games. This solution will allow performers to "maintain an

adequate hydration status in order to maximize performance". (Phillips et al, 2011, Pg 576).





If hydration is not maintained, then performance can reduce during participation meaning

dehydration can occur.





2.2 Games based performance test.

Bangsbo (2008) created an intermittent recovery test designed for team games which

involved a lot of stopping and starting.

As the majority of the participants are from a football background, it is appropriate to see if

the test is reliable. A study by Barbosa Coelho et al (2012) used the Yo-Yo test as a

dehydrating exercise test whilst also looking at urine osmolality.

The participants undertook a Yo-Yo test before playing a football match. Once the Yo-Yo test

was completed, a urine sample was collected (Pre-match), a game of football was played and

a final urine sample was collected (post-match). The participants were only allowed to drink

water whilst playing.

The results show an increase in hydration levels post performance compared to pre

performance straight after completing the Yo-Yo test. The key data is presented below.

Osmolality

(oSmol/kg)

MAIN (n=24) INT (n=13) CON (n=5)

Pre 817.2 ± 168.6 853.2 ± 61.3 753.8 ± 126.1

Post 795.6 ± 100.6 811.8 ± 52.9 841.6 ± 79.4

Table 1: Main group (MAIN), Intermediate group ( INT), Control group (CON) *Signif icantly different

compared to pre match values (p<0.05), (mean±SE).





2.3 Carbohydrates before exercise.

Davison et al (2008) found a number of studies which support the notion of consuming

carbohydrates immediately before exercising. In addition to this, all three studies show that

consuming carbohydrates immediately before exercise will also increase performance.

Name of researcher Timing of Carbohydrate ingestion Exercise outcome

Nicholas et al. (1995) Immediately before performance. Increased performance.

Tsintzas et al. (1996) Immediately before performance. Increased performance.

Patterson and Gray.

(2007)

Immediately before performance. Increase performance.

Table 2: Breakdown of researchers, t imings and outcome of exercise.

Correia-Oliveira (2013) performed a review of the current research into strategies of

carbohydrate intake and the effect on performance. Two of the reviews link directly to the

study due to the carbohydrate beverage being consumed shortly before performance.

Although these studies are both relevant, they give different findings to each other.

Anantaraman (1995) found that a beverage consumed just two minutes before undertaking

exercise does actually improve performance. Contradictory evidence comes from Palmer

(1998) who found that beverages consumed fifteen minutes before exercise reduced

performance. A reason for these different results could be down to the food consumed by

participants before exercising. Eating a high fat meal up to four hours before performing can

result in a lower oxidation of carbohydrates whilst exercising (Okano, Sato, Takumi &

Sugawara, 1996), compared with a low fat meal which will have the opposite effects.





2.4 Stereotypical hydration beverages vs carbohydrate beverages.

As there are so many commercial sports drinks available, teams and individual performers

have tried to create their own sports drinks to affect hydration and exercise performance.

Some of the better known stereotypical hydration beverages can be found below. With

these in mind, the study is looking to provide an effective carbohydrate beverage solution

which increases performance and has a positive effect on osmolality, whilst also offering an

effective beverage other than the idealised hydration drinks below.

A number of studies have looked at the effectiveness of drinks such as lemon tea, coconut

water and pickle juice. Wong and Yajun (2011) compared the effectiveness of lemon tea

against water and a carbohydrate beverage which consisted of a six point six percent

solution. Participants were exposed to all drinks. The procedure involved a run for sixty

minutes at seventy percent of VO2 Max. The carbohydrate beverage was retained the most

post-exercise, compared to the lemon tea and water. In terms of hydration, the

carbohydrate beverage was most effective at rehydrating the body compared to water and

lemon tea.

Another study by Kalman et al (2012) compared the effects of coconut water and a five point

five percent carbohydrate concentration drink on recreational performers. The participants

underwent two bouts of walking or jogging followed by a ten minute rest. Once the

dehydrating exercise was completed, the participants took onboard their specified beverage.

Immediately after performance there was no significant difference between the drinks in

terms of plasma osmolality, however three hours post dehydrating exercise the sports drink

had a slight decrease in plasma osmolality compared to the coconut water (289oSmol/kg

compared to 291oSmol/kg).





Miller, Mack & Knight (2009) studied the effect of pickle juice against a carbohydrate

beverage and water. Participants drank one of the three beverages and were told to remain

seated for an hour before a urine sample was given and compared to the pre drink sample

collected. The samples found that urine osmolality was lower within the carbohydrate drink

(368.8 oSmol/kg) than either the pickle juice (507.7 oSmol/kg ) or water (381.0 oSmol/kg).

Although no testing was carried out, this study gives us an indication of how effective a

carbohydrate beverage is over flavoured drinks. For these reasons, no flavoured drinks will

be used in the study.





2.5 Effect of Carbohydrates on Performance.

Research into performance and carbohydrates has been vigorously undertaken. Studies by

Bergstro (1967), Baldwin (2003) and Johnson (2006) have all confirmed that carbohydrates

increase performance levels for athletes.

A number of focused studies by Lima-Silva (2009, 2010 and 2011) have confirmed that

carbohydrates have a positive effect on short, high intensity exercises. These findings are

relevant to intermittent sports due to the short but high intensity runs completed in the

trials.

Research by Mitchell et al (1988) into the effects of carbohydrate solutions on intermittent

exercise performance found that a five percent solution is effective at increasing

performance over a placebo drink. This five percent solution indicates the lowest percentage

bound solution, with anything lower than a five percent solution having little effect on

performance. This is confirmed by the findings of Ingle, Cooke & King (2011) where a two

point five percent solution was used. Details of this study can be found later in this section.

A six point four carbohydrate beverage will significantly increase running performance over a

one hour period. This is compared to a colour and taste matched placebo (Rollo & Williams,

2009). This beverage is close to a five percent beverage like the one used in this study. This

means that a five percent beverage should also cause significant differences over a placebo

beverage when performing.

Research into the effect of a seven percent carbohydrate beverage on football players'

performance found no significant improvement on performance. However, researchers did

find that increasing carbohydrate intake before performance does improve time to fatigue





(Goedecke et al, 2013). This research indicates that different solutions may be applicable

depending on the sport which is being played.

Another study using an eight percent carbohydrate beverage pre performance also found an

increase in running performance. The other drink used in the study was a two point five

percent carbohydrate beverage, but no significant readings were found in relation to

performance for this two point five percent drink (Ingle, Cooke & King, 2011) suggesting the

solution concentration was too low.

Gomes et al (2013) found that a ten percent carbohydrate solution improves performance of

intermittent sports, specifically within tennis matches. Although tennis is not a continuous

exercise, such as running, the study still shows that a ten percent beverage will have an

effect on performance.

Other research in this area by McGawley, Shannon & Betts (2012) found that an eleven

percent carbohydrate solution, which is close to the ten percent solution which will be used

in the study, is effective in improving running performance for triathlon competitors.





2.6 Concentration of carbohydrate beverages and effects on osmolality levels.

In terms of carbohydrate concentrations, there are many studies looking for the optimum

solution of drinks and the effect they have post performance. Two studies, by Evans,

Shirreffs & Maughan (2009) and Shirreffs (2009), investigated the effects of a carbohydrate

beverage which has a concentration of ten percent or higher.

Below is a table provided within the first study (Evans, Shirreffs & Maughan. 2009)

underlining the differences in carbohydrate and osmolality percentage. * Indicates the drink

was not tested.

Drink consumed Carbohydrate % Osmolality %

Gatorade 6 280

Isostar 7 289

Lucozade Sport 6.4 285

Powerade 6 280

Orange Juice 10 660

Apple Juice 13 *

Tomato juice 3 *

Cola 11 700

Oral rehydration solution 2 250

Bottled water 0 9

Milk 5 288

Table 3: The composit ion of selected UK based sports drinks and other beverages. Carbohydrate content

is taken from drink labels. Other data from samples analysed in the laboratory.

This table shows that the higher the carbohydrate solution, the more dehydrated the

participants were after exercise testing. Endorsement for this notion comes from the second

study by Shirreffs (2009) where he found that drinks which contain between a six percent

and seven percent carbohydrate solution are effective in reducing osmolality levels (280-

289 oSmol), compared to drinks which contained a carbohydrate solution of above ten





percent (660-700 oSmol). He also found that very high solutions (ten percent or higher) of

carbohydrate will result in "the secretion of water into the intestine therefore increasing the

likelihood of dehydration" (Shirreffs, 2009, pg 377).

A different study by Evans, Shirreffs & Maughan (2009) also looked at the effect of a zero,

two and ten percent carbohydrate beverage and the effects they each had on osmolality. In

terms of urine osmolality, there were no differences observed immediately after exercise,

however, after an hour there was a drop in the two percent osmolality level indicating the

two percent drink has an effect over the ten and zero percent drinks. This reinforces the

previous point that a ten percent drink may be too high, but, promotes the fact that a lower

percentage solution does have an effect on osmolality levels post performance.

Williams and Blackwell (2012) looked at the effect of beverages drunk whilst training and the

effect they have on osmolality. Participants were encouraged to drink their normal choice of

beverage whilst training. The findings were substantial. Between the average urine sample

pre performance (350 oSmol) the osmolality level rose by 632 oSmol to 910 oSmol. These

figures reiterate the importance for hydration drinks to be consumed whilst performing.

Shirreffs (2003) found that “values greater than 900 oSmol used as an indicator of

hypohydration” (Shirreffs (2003) pg 8).

In terms of maintaining osmolality levels, a study by Kovacs (2008) looked at how fluid

ingestion effects performance of tennis players in a competitive environment. What he

found was that tennis players began to get cramp after a long period of play on the court

which was caused due to a lack of sodium. A specific carbohydrate solution would limit or

stop this cramping if consumed whilst competing, therefore improving performance.





A study looking at the role of carbohydrate ingestion for endurance performers whilst

exercising in the heat found that a ten percent solution was best for absorption into the

body during these conditions. They also found that this ten percent solution avoided

stomach upsets, cramps and muscle failure for the endurance performers (Nutrition For

Endurance: Finding Another Gear, 2014).





3.0 Methodology.

3.1 Subjects.

Nine exercise trained athletes were used for the study. Three Girls (Average age: nineteen

years, six months and height: 171.6 cm) and six boys (Average age: twenty years, five months

and height: 180.3 cm) Recruitment was by a convenient sampling method. The study was

approved after an appropriate ethic form was submitted and approved. All players

completed and signed consent and medical forms prior to testing. Some subjects had minor

medical concerns but still gave consent to participate in the study.

3.2 Apparatus.

Cones

Measuring tape

CD

CD player

Test pots

Pipette

Osmometer

3.3 Test Procedure.

3.31. Prior to testing, all paper work including full risk assessments were completed in

order for the testing to take place. Participants had to complete consent and medical forms

(Appendix B and C) before final numbers were confirmed. Urine samples were given by





participants, so a private toilet was arranged for participants to use. Each drink was labelled

clearly with participants numbers on to avoid confusion. To avoid placebo effects, a double

blind study took place with someone outside the research group making up the

carbohydrate drinks for each participant. The testing includes the use of three 300ml

beverages. Participants consumed all the drinks. The drinks consisted of: five percent

carbohydrate; ten percent carbohydrate and a placebo drink with no carbohydrate in. Drinks

were given to participants with their unique number on it in a 300ml bottle.

3.32. On each of the four test days, before testing took place, all participant medical forms

had to be checked and appropriate caution taken for risks that were identified in the risk

assessment forms. Participants had to report to the sports hall half an hour before testing

took place in order to warm up and prepare for testing. Participants were instructed to

consume the carbohydrate beverage up to fifteen minutes before testing. Participants were

then required to undertake the maximal exercise activity Yo-Yo test (Bangsbo, J, 2008).

Participants were required to know their unique participant number for post performance.

3.33. When participants were finished, their score was recorded next to their participant

number. Urine pots were ready for participants to give a sample in. Within minutes after

exercise the samples were collected then put into a secure box and transferred over to the

lab.





3.4 Statistical analysis.

All data was tested for normality using a descriptive statistics test in order to understand

which final test should be undertake on the data. The data would be presented as a mean ±

SD. Significant factor was taken as p <0.05.

A Repeated Measures ANOVA test was completed in order to establish if the results were

significant. If the results show as significant, a Post Hoc test will be used to identify where

the significant differences have occurred. If the results do not show as significant, then no

Post Hoc test will be looked at and the Null Hypothesis will be accepted for the study. The

data will be presented as a mean ± SD. Significant factor taken as p <0.05.

Results for Yo-Yo test in relation to each beverage will be presented as a stem and leaf

diagram.





3.5 Drinks justification.

After studying the research, the drink solutions to be used in the study will be: a placebo

beverage; a five percent carbohydrate beverage; and a ten percent carbohydrate beverage.

A placebo drink is being put in place to compare against carbohydrate solutions. A five

percent carbohydrate beverage is being used because of the research findings by Kalman et

al 2012 where a five point five percent beverage had significant results for fitness trained

performers which is the standard the participants in the study will be at. Research by Evans,

Shirreffs & Maughan (2009) found lower percentage carbohydrate drinks cause lower

osmolality levels post performance. A ten percent carbohydrate beverage will be used

because research by McGawley, Shannon & Betts (2012) and Ingle, Cooke & King (2011)

found a ten percent carbohydrate beverage to improve performance when exercising.





4.0 Results.

4.1 Normality checks.

Placebo check Tests of Normality

Kolmogorov-Smirnova Shapiro-Wilk

Statistic df Sig. Statistic df Sig.

Placebo .311 9 .012 .789 9 .015

a. Lilliefors Significance Correction

Table 4: Tests of normality on the Placebo beverage.

5% Check Tests of Normality



5% .209 9 .200* .944 9 .625

*. This is a lower bound of the true significance.


Table 5: Tests of normality on the Five percent beverage.

10% Check Tests of Normality



10% .142 9 .200* .938 9 .563

*. This is a lower bound of the true significance.


Table 6: Tests of normality on the Ten percent beverage.

From the normality tests performed, it can be seen that the placebo beverage does

not indicate normality. However, with both the five percent (Table four) and ten





percent (Table five) drinks, it can be seen that the data is normally distributed. This is

evident by looking at the Sig number in the Kolmogorov-Smirnov section of the

table.





4.2 ANOVA repeated measures tests.

A one-way repeated measures ANOVA was undertaken in order to compare the

results of urine osmolality across the three beverage consumption conditions:

placebo; five percent and ten percent. The findings, which include mean and

standard deviation, can be found in the table below (Table six).

Descriptive Statistics

Drink Consumed Mean Std. Deviation N

Placebo 527.78 oSmol 220.33 oSmol 9

5% 524.44 oSmol 237.76 oSmol 9

10% 597.78 oSmol 268.04 oSmol 9

Table 7: Comparison of Mean and Standard Deviation f igures between the variat ion of drinks.

Table 8: Results from ANOVA test.

Tests of Within-Subjects Effects

Measure: Osmolality

Source Type III Sum of

Squares

df Mean Square F Sig. Partial Eta

Squared

Drinks

Sphericity Assumed 30866.667 2 15433.333 .548 .588 .064

Greenhouse-Geisser 30866.667 1.376 22431.090 .548 .529 .064

Huynh-Feldt 30866.667 1.568 19688.656 .548 .550 .064

Lower-bound 30866.667 1.000 30866.667 .548 .480 .064

Error(Drinks)

Sphericity Assumed 450466.667 16 28154.167

Greenhouse-Geisser 450466.667 11.009 40919.783

Huynh-Feldt 450466.667 12.542 35916.914

Lower-bound 450466.667 8.000 56308.333





When using ANOVA with Repeated Measures testing, using a lower-bound correction, the

mean score for osmolality levels in performers are statistically significant. (F(1.00, 8.00) =

0.480, p <0.05).





4.3 Post Hoc Test.

Pairwise Comparisons

Measure: Osmolality

(I) Drinks (J) Drinks Mean

Difference (I-J)

Std. Error Sig.a 95% Confidence Interval for

Differencea

Lower Bound Upper Bound

12 3.333 96.796 1.000 -288.580 295.247

3 -70.000 84.607 1.000 -325.154 185.154

2 1 -3.333 96.796 1.000 -295.247 288.580

3 -73.333 47.346 .480 -216.118 69.452

31 70.000 84.607 1.000 -185.154 325.154

2 73.333 47.346 .480 -69.452 216.118

Based on estimated marginal means

a. Adjustment for multiple comparisons: Bonferroni.

Table 9: Post Hoc Test results.

Here it can be seen exactly where the difference between the drinks lie. Significant

results can be observed between: drink one (placebo) and drink two (five percent)

and also drink one (placebo) and drink three (ten percent). No significant results

were found between drink two (five percent) and drink three (ten percent).

This demonstrates that osmolality results were significantly lower after consumption

of both a five percent and ten percent beverage than a placebo beverage. In both

places significance was identified.





4.4 Yo-Yo scores for each drink.

Placebo beverage.

Table 10: Box plot showing results of Yo-Yo test for Placebo beverage.

In the Yo-Yo test when the placebo drink was consumed, the average score was level twenty

three. The highest score was level thirty six and the lowest score was level nine.

Five percent carbohydrate beverage.

Table 11: Box plot showing results of Yo-Yo test for f ive percent carbohydrate beverage.

In the Yo-Yo test when the five percent carbohydrate drink was consumed, the average score

was level twenty four. The highest score was level thirty seven and the lowest score was

level ten.





Ten percent carbohydrate beverage.

Table 12: Box plot showing results of Yo-Yo test for ten percent carbohydrate beverage.

In the Yo-Yo test, when the ten percent carbohydrate drink was consumed, the average

score was level twenty seven. The highest score was level forty two and the lowest score was

level nine.





5.0 Discussion.

The aim of the study is to Investigate if different solutions of carbohydrates affect

performance and hydration.

5.1 Statement of main findings.

When using an ANOVA with Repeated Measures testing, using a lower-bound correction, the

mean score for osmolality levels in performers is statistically significant. (F(1.00, 8.00) =

0.480, p <0.05). Significant results can be observed between the placebo and five percent

beverage and also between placebo and ten percent beverage.

The key results in this study show that both a five percent and a ten percent solution cause

lower osmolality, indicating that participants are more hydrated post performance than

those who consumed the placebo beverage. When comparing the two carbohydrate

beverages, there were no significant differences found, indicating similar effects on

osmolality. When looking at the mean results, the closest results were between the five

percent beverage (524.44 oSmol) and the placebo (527.78 oSmol). The ten percent mean

was 597.78 oSmol respectively.

When looking at the scores of the Yo-Yo test and the drink consumed, there's an increase in

the average reflecting the amount of carbohydrate in the drink. From the placebo average

score (twenty three) to the five percent average score (twenty four), there is a relatively

small level gap. But, when looking at the gap between the five percent average and the ten

percent average (twenty seven) we find an increase of three levels in the final Yo-Yo result,

which is a large increase. The placebo high score was level thirty six and the five percent





drink high score was level thirty seven. However the ten percent drink had a high score of

level forty two, a significant five level increase from the five percent drink.





5.2 Support and comparison for osmolality findings.

Support for the findings come from Kalman et al (2012) where a five percent beverage

caused significant results for recreational performers. Further support from Evan, Shirreffs

and Maughan (2009) is found. This is due to smaller percentage carbohydrate drinks causing

lower osmolality levels in performers post exercise. The reason the ten percent beverage

mean (597.78 oSmol) is higher is attributable to the solution being too concentrated to break

down in time for the carbohydrates to have an effect on performance. Comparing this to

research by Shirreffs (2009), similar results can be seen where a ten percent solution or

higher could cause performers to become more dehydrated. This is due to the secretion of

water into the intestines. Shirreffs research provides a reason as to why the ten percent

beverage has a higher average osmolality level. Comparing the findings in the study plus the

paper mentioned by Shirreffs, with research by Nutrition For Endurance: Finding Another

Gear (2014), this is contradictory evidence. Furthermore, reports about a ten percent

carbohydrate beverage is effective for absorption into the body for endurance performers.





5.3 Support and comparison for performance in Yo-Yo test.

The average score for each of the beverages is as follows: placebo beverage, level twenty

three; five percent beverage, level twenty four; and ten percent beverage, level twenty

seven. The average grows as the carbohydrate percentage increases. These findings are

supported by Goedecke (2013) where time to fatigue is increased by the carbohydrate

solution. Compared to the study by McGawley, Shannon & Betts (2012), a fourteen point

four percent carbohydrate solution was found to increase running performance. This

supports the findings in the study and Goedecke's research in that the more carbohydrate

available, the better performance will be.

When comparing the solution used in this study with research by Mitchell et al (1989) we see

that this high carbohydrate solution may be effective in some cases, but, lower solutions can

also be effective. Mitchell et al found that a seven point five percent solution enhanced

performance significantly for cycling time trials and later established a seven point five

percent solution as causing a significant difference in the same trials compared to drinking

water without any additive.





5.4 Limitations and recommendations for future research.

There are several limitations with the study. The lower bound statistic was taken to show a

significant difference between results. Although, these significant differences are shown,

accepting the lower bound statistic is correcting the degrees of freedom for the "worst case

scenario" (Laerd Statistics, 2013). This is establishing that results are significant at a worst

case scenario. Another limitation to the study is the lack of control over participants before

the testing took place. The challenge here is that with a mixed group of participants, they will

consume different quantities and types of beverage prior to participating in the tests. This

could affect osmolality levels which were taken after performing. For example, one

participant may have consumed four pints of water in the morning before doing testing and

someone may have had only a cup of tea, coffee or other soft drink. This will mean a more

hydrated person is taking part before the drinks mixed specifically for the testing are even

consumed. If research in this area was undertaken again, an overnight and morning fast

protocol would have to be used so that participants are all in the same state before exercise

takes place. A study by Evans, Shirreffs, & Maughan. (2012) had undertaken a thirteen hour

fluid restriction period before consuming a carbohydrate beverage chosen by the researcher.

The carbohydrate drink is not important but the overnight (thirteen hour) fast, prior to the

drinks being consumed, is. This period will allow the participants to be in a similar hydration

state before starting the test. This overnight fast will act as an element of control over drink

consumption before testing. This means outliers for osmolality levels like the one outlined

above will become less likely.

Recommendations for further research would be to explore the seven point five percent

carbohydrate beverage. A lower solution of between six and seven percent and a higher,





eight percent would be good to perform research on. This would show the upper and lower

limits and the effects on osmolality and performance.





5.5 Conclusion.

The results have shown that a ten percent beverage is too high to have an effect on

osmolality. This supports the findings from Shirreffs (2009) where the secretion of water into

the intestines causes performers to become more dehydrated. Although the ten percent

solution showed signs of performance enhancement through the results from the Yo-Yo test,

research into this area also found a six and a seven point five percent carbohydrate solution

to have effects on osmolality and performance. A lower carbohydrate solution which will

have an effect on both osmolality and performance should be looked into further.

This study has looked at the effects of different carbohydrate solutions on both performance

and osmolality. What the study has done for trained games players is establish an upper

carbohydrate limit that will maximise performance and hydration in sport. This is the limit to

which a carbohydrate beverage will have an effect on both performance and osmolality.

Team players need both performance enhancement for whilst they are participating and also

hydration in order to stop a reduction in their performance and dehydration occurring. This

study is providing an understanding through controlled testing into the effects of specific

mixed quantities of carbohydrate solutions on both performance and osmolality. With

further development and research in the area of sports drinks, a specific solution could be

found which will optimise both performance and osmolality for game performers.

At the end of the study, hypothesis H1 and H2 will be accepted. H1: There is significant

difference in osmolality recorded between each drink trial. H2: There is significant difference

between the placebo drink and carbohydrate drinks.





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7.0 Appendices.

7.1 Appendix A.





7.2 Appendix B.



7.3 Appendix C.

Documents

A study into the effect of carbohydrate solutions, ingested before exercise, on hydration levels post performance