1. The document reports on a study that examined the effects of creatine versus a placebo on repeated sprint performance, maximum strength, and power in 15 participants. 2. The results showed no significant differences between the creatine and placebo groups in pre-sprint or post-sprint times, rates of perceived exertion, concentric and eccentric peak torque, or jump heights. 3. While both groups improved slightly from pre to post testing, the creatine group demonstrated slightly greater improvements than the placebo group in some measures like decreased sprint times, increased concentric peak torque, and increased jump heights. However, all differences were small with no statistical significance.

1. 1
BSc (Hons) Sports Science and Coaching
Scientific Laboratory Report – The
Effects Of Creatine On Repeated
Sprint Performance, Maximum
Strength And Power.
SPO033-3 Ergogenic Aids and Sports Performance
Group 15
I declare that this is our own work and should this declaration
be found to be untrue we acknowledge that we may be guilty of
committing an academic offence.

2. 2
Introduction
There are a number of substances that are nutritionally or pharmaceutically to aid for a better
performance; creatine is the most popular substance to date. Creatine is produced
endogenously, predominately in the liver, kidneys and pancreas (Cooper et al, 2012). It is
found that 95% of the bodies’ creatine stores are found in the skeletal muscles whilst the
remaining 5% is distributed in the brain, liver, kidney and testes (Persky & Brazeau, 2001).
Creatine is also present in the diet from meats, therefore, it is said vegetarians have lower
forms of creatine in their body (Burke, et al. 2008). Creatine is a substance that helps enhance
sport performance on short durations, predominately anaerobic exercises. It is important for
exercise performance as creatine can aid sport performance as a supplement to an athlete’s
diet (Buford et al. 2007). Creatine Monohydrate (CM) is seen as the most widely used
supplement orally (Volek et al. 1996). Ingested, CM has then shown to increase fat free mass,
strength, and the ability to recover more effectively during exercise (Cooper et al 2012).
Throughout this assignment it will discuss and examine the effects of creatine on 15
participants who carried out sprints, maximum strength and power performance under the
influence of either a creatine substance or a placebo.
Statistical Analyses
Data was collected from sixteen subjects (n = 16). Statistical analysis was conducted using
SPSS statistic 19 software (SPSS Inc., Chicago, IL, USA). Independent t-test was used to
assess changes within subjects in both 15m sprint trials for creatine and placebo groups. All
data was reported as the mean values ± standard deviations (SD). The normal distribution was
established using Q-Q plots. The significant difference was accepted p ≥ 0.05. Data equality

3. (SD) between the pre and post 15m sprints for both groups was examined using dot plots. The
3
data is presented with a 95% confidence interval.
Results
Pre-Sprint and Post-Sprint time
Employing independent t-test for achieved results is indicated in table 1 that no significant
difference (p ≥ 0.05) occurs in the 15m Pre-Sprint trials for both Creatine and Placebo
groups.
Table 1. Pre-Sprint time (s) for Creatine and Placebo groups (mean ± SD).
Trials P r e - Sprint (Creatine Group) P r e - Sprint (Placebo Group)
Trial 1 2.693 ± 0.130 2.736 ± 0.172
Trial 2 2.633 ± 0.089 2.730 ± 0.216
Trial 3 2.679 ± 0.153 2.676 ± 0.152
Trial 4 2.705 ± 0.162 2.699 ± 0.189
Trial 5 2.695 ± 0.163 2.715 ± 0.187
Trial 6 2.674 ± 0.166 2.676 ± 0.181
Trial 7 2.684 ± 0.186 2.698 ± 0.180
Trial 8 2.685 ± 0.203 2.723 ± 0.218
Trial 9 2.675 ± 0.165 2.719 ± 0.227
Trial 10 2.678 ± 0.185 2.738 ± 0.217
Trial 11 2.674 ± 0.187 2.723 ± 0.201
Trial 12 2.706 ± 0.307 2.750 ± 0.216
Trial 13 2.696 ± 0.191 2.711 ± 0.195

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Trial 14 2.679 ± 0.212 2.736 ± 0.194
Trial 15 2.658 ± 0.198 2.714 ± 0.216
No significant difference (p ≥ 0.05) was observed in the 15m Post-Sprint trials between both
groups (Table 2).
Table 2. Post-Sprint time (s) for Creatine and Placebo groups (mean ± SD).
Trial P o s t -Sprint (Creatine Group) P o s t -Sprint (Placebo Group)
Trial 1 2.708 ± 0.492 2.721 ± 0.147
Trial 2 2.680 ± 0.143 2.700 ± 0.164
Trial 3 2.663 ± 0.084 2.681 ± 0.125
Trial 4 2.651 ± 0.818 2.699 ± 0.207
Trial 5 2.678 ± 0.130 2.680 ± 0.157
Trial 6 2.698 ± 0.225 2.694 ± 0.148
Trial 7 2.680 ± 0.177 2.680 ± 0.140
Trial 8 2.648 ± 0.146 2.688 ± 0.110
Trial 9 2.669 ± 0.146 2.686 ± 0.145
Trial 10 2.630 ± 0.123 2.671 ± 0.136
Trial 11 2.685 ± 0.164 2.731 ± 0.194
Trial 12 2.639 ± 0.150 2.719 ± 0.178
Trial 13 2.665 ± 0.157 2.674 ± 0.153
Trial 14 2.628 ± 0.155 2.723 ± 0.142
Trial 15 2.651 ± 0.165 2.671 ± 0.112

5. In the pre-sprint the creatine group showed a decrease in time of 0.59% and by 0.81% in the
placebo group. For post-sprint trials the creatine group showed a decrease in time of 1.11% in
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comparison to Placebo group (Figure 1).
2.680 ± 0.180
2.716 ± 0.198
2.664 ± 0.169
2.694 ± 0.150
2.7300
2.7200
2.7100
2.7000
2.6900
2.6800
2.6700
2.6600
2.6500
2.6400
2.6300
Pre-Sprint
(Creatine
Group)
Pre-Sprint
(Placebo Group)
Post-Sprint
(Creatine
Group)
Post-Sprint
(Placebo Group)
Time (s)
Group
Figure 1. Average decrease in time (s ± SD) in pre-sprint and post-sprint 15 trials in creatine
and placebo groups.
Pre-Sprint and Post-Sprint RPE
There was a similarity of results when using Rate of Perceived Exertion (RPE) this was used
in all 15m pre-sprint and post-sprint trials (Table 3). No significant difference (p ≥ 0.05) was
found in all 15m sprint trials.
Table 3. Pre-Sprint RPE for Creatine and Placebo groups (mean ± SD).
Trial P r e - Sprint RPE (Creatine Group) Pre-Sprint RPE (Placebo Group)
Trial 1 6.50 ± 1.414 8.38 ± 2.825
Trial 2 6.75 ± 1.389 9.00 ± 2.976

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Trial 3 7.50 ± 1.414 9.13 ± 2.532
Trial 4 8.25 ± 1.669 9.63 ± 2.387
Trial 5 9.13 ± 2.295 10.25 ± 2.493
Trial 6 9.63 ± 2.669 10.88 ± 2.696
Trial 7 10.63 ± 2.615 11.13 ± 2.748
Trial 8 11.25 ± 2.915 11.88 ± 2.295
Trial 9 11.75 ± 2.964 12.25 ± 2.659
Trial 10 12.25 ± 2.964 12.75 ± 2.375
Trial 11 12.38 ± 3.114 13.00 ± 2.563
Trial 12 12.75 ± 2.816 13.50 ± 2.726
Trial 13 13.38 ± 2.722 13.88 ± 2.696
Trial 14 13.50 ± 2.878 14.13 ± 2.800
Trial 15 14.00 ± 2.777 14.50 ± 2.976
Also in the 15m post-sprint trials the RPE had no significant difference (p ≥ 0.05) (Table 4).
Table 4. Post-Sprint RPE for Creatine and Placebo groups (mean ± SD).
Trial P o s t - Sprint RPE (Creatine Group) Post -Sprint RPE (Placebo Group)
Trial 1 6.63 ± 1.408 7.50 ± 1.414
Trial 2 6.88 ± 1.356 7.63 ± 1.506
Trial 3 7.63 ± 1.685 7.88 ± 1.356
Trial 4 8.13 ± 1.808 8.50 ± 1.604
Trial 5 8.75 ± 1.753 8.88 ± 1.808
Trial 6 9.38 ± 1.598 9.38 ± 1.996
Trial 7 9.63 ± 1.923 9.88 ± 1.808

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Trial 8 10.50 ± 2.070 10.25 ± 1.982
Trial 9 11.25 ± 2.375 10.63 ± 1.598
Trial 10 12.00 ± 2.138 11.63 ± 1.923
Trial 11 12.25 ± 2.375 12.13 ± 1.885
Trial 12 12.63 ± 2.387 12.50 ± 1.927
Trial 13 13.50 ± 2.777 12.88 ± 1.808
Trial 14 14.13 ± 3.091 13.63 ± 2.326
Trial 15 14.88 ± 3.271 14.13 ± 2.642
For the 15m pre-sprint trials the creatine group showed a decrease in RPE of 0.94% where as
the placebo group showed an increase of 9.72%. For 15m post-sprint trials the placebo group
indicated a decrease in RPE by 0.47% than in comparison to the creatine group (Figure 2).
10.64 ± 2.441
11.62 ± 2.650
10.54 ± 2.134
11.80
11.60
11.40
11.20
11.00
10.80
10.60
10.40
10.20
10.00
Figure 2. Average decrease in RPE (mean ± SD) in Pre-Sprint and Post-Sprint 15 trials in
Creatine and Placebo groups.
10.49 ± 1.839
9.80
Pre-Sprint RPE
(Creatine Group)
Pre-Sprint RPE
(Placebo Group)
Post-Sprint RPE
(Creatine Group)
Post-Sprint PE
(Placebo Group)
RPE
Group

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Pre- and Post- Concentric and Eccentric Peak Torque and Height in Height Jumps
No significant difference (p ≥ 0.05) was observed in concentric and eccentric peak torque in
Pre- and Post- trials in both groups (Table 5).
Table 5. Pre- and Post- Concentric and Eccentric Peak Torque (N*m) in Height Jump.
Height Jump Creatine Group Placebo Group
Pre-Concentric Peak
Torque
1003.000 ± 254.966 944.375 ± 328.443
Post-Concentric Peak
Torque
1113.625 ± 230.136 971.250 ± 332.290
Pre-Eccentric Peak Torque 1181.875 ± 206.983 1206.500 ± 423.799
Post-Eccentric Peak
Torque
1200.125 ± 240.351 1138.375 ± 435.762
There was no significant difference (p ≥ 0.05) found in all 3 jumps in pre and post trials for
both creatine and placebo groups (Table 6).
Table 6. Pre- and Post- Jump Height (cm) in Height Jumps.
Height Jump Creatine Group Placebo Group
Pre- Jump Height, Trial 1 47.003 ± 6.343 46.169 ± 6.100
Pre- Jump Height, Trial 2 49.620 ± 5.644 46.181 ± 6.029
Pre- Jump Height, Trial 3 47.623 ± 4.350 48.761 ± 9.400
Pre- Jump Height, Mean 48.083 ± 5.093 47.038 ± 6.412
Post- Jump Height, Trial 1 44.279 ± 9.880 44.233 ± 6.488

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Post- Jump Height, Trial 2 45.334 ± 8.866 44.851 ± 5.818
Post- Jump Height, Trial 3 45.503 ± 10.017 46.696 ± 7.298
Post- Jump Height, Mean 45.039 ± 9.482 45.260 ± 6.093
1400.000
1200.000
1000.000
800.000
600.000
400.000
200.000
0.000
Peak Torque (N*m)
Figure 3. Concentric and Eccentric Peak Torque (N*m) in Height Jump in Pre- and Post-trials
in Creatine and Placebo groups.
In figure 3 there is an increase in concentric peak torque by 9.93% and 2.77% in post- trials
for both creatine and placebo groups. The same tendency occurred in eccentric peak torque
for creatine group. Post-trial measurements are higher by 1.52% in the creatine group. The
decrease in eccentric peak torque for post-trials in placebo group was 5.65%. Measurements
for post-concentric and eccentric trials were higher in the creatine group in comparison with
the placebo group 12.78% and 5.15% for post-concentric and eccentric peak torque
respectively (Figure 4).
Creatine group
Placebo group

10. 51.000
50.000
49.000
48.000
47.000
46.000
45.000
44.000
43.000
42.000
41.000
Pre-
Jump
Height,
Trial 1
Pre-
Jump
Height,
Trial 2
Pre-
Jump
Height,
Trial 3
Post-
Jump
Height,
Trial 1
Post-
Jump
Height,
Trial 2
Post-
Jump
Height,
Trial 3
Height (cm)
Figure 4. Jump Height (cm) in Height Jumps in Pre- and Post-3 trials in Creatine and Placebo
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groups.
Overall the jump height decreased in both the creatine and placebo groups by 6.33% and
3.77% in pre and post- trials respectively (Figure 5). Jump height increased in the creatine
group during the pre- trials by 2.17% and post-trial difference by 0.49%.
Creatine group
Placebo group
48.083 ± 5.093
47.038 ± 6.412
45.039 ± 9.482
45.260 ± 6.093
48.500
48.000
47.500
47.000
46.500
46.000
45.500
45.000
44.500
44.000
43.500
Creatine group Placebo group
Jump height (cm)
Pre- Jump Height, Mean
Post- Jump Height, Mean

11. Figure 5. Average Jump Height (cm) in Height Jumps in Pre- and Post- trials in Creatine and
11
Placebo groups.
Discussion
The objective of this study was to investigate the effects of creatine supplementation on
repeated sprint performance, maximum strength and power. The main findings indicated that
there were no significant findings in pre and post creatine and placebo sprints, jumps and leg
contraction trials. From these findings we can state that creatine supplementation did not have
a profound effect on enhancing physical performance.
Supporting our findings, (Glaister, et al. 2006), conducted at study on 42 physically active
men on repeated sprint performance on short-term creatine monohydrate supplementation.
The major findings of this study were that creatine supplementation had no significant effect
on all measures; fastest time, mean time, fatigue or posttest and bloody lactate concentration.
On the other hand, Gutierrez-Sancho, et al (2006), found that creatine supplementation
consistently showed biomechanical, body composition and power changes in humans during
a meto analyses. They also found the placebo group showed further improvement in
performance. This states that not only does creatine enhance performance but equally the
placebo can influence participant’s performance.
Our results supported the statement that effects of oral creatine supplementation have no
influence on performance (Lee, et al. 2011). In contrast by Bemben and Lamont (2005), they
state that creatine supplementation considerably effects strength irrespective of an
individual’s sport, sex or age. Additionally, the effects of short term creatine supplementation

12. enhanced maximal anaerobic power and sprinting ability (Schneiker et al. 2006); this
however, is not well addressed by other researchers. Specifically creatine monohydrate (CM)
is a limitation to enhancing performance in anaerobic activities, as stated by Jäger et al.
(2011), as it is not stable enough to show any significant differences. Creatine is an
ampholytic amino acid which has low solubility in water and is one of its main restraints
(Miller-Keane and O'Toole, 2003). Creatine easily mixes with phosphate to form
phosphocreatine or creatine phosphate; this is located in the skeletal muscle (Miller-Keane
and O'Toole, 2003). Therefore, muscle contraction is essential for aiding storage of high-energy
phosphate bonds, this gives us reasoning to why our study obtained a particular set of
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results.
Mechanical reliability of the Kin-Com test in both static and dynamic modes has been
examined by other researchers. However, the reliability for concentric and eccentric peak
torque (PT) values at angle-specific torques has currently not been agreed (Arnold, et al.
1993). Similarly, Tredinnick and Duncan (1988) states there is variability whenever testing
and retesting the peak torque values of the participants. This is shown due to the participants
feeling fatigued from powerful short executions or a combination of being unfamiliar with
the methods used as part of the Kin-Com dynamometer testing. Based on these factors,
Wilhite et al (1992) suggested using the Kin-Com test there should be intervals of minimising
and maximising speeds for the participants to get a greater understanding of the process
needed to measure their concentric and eccentric performances. However, within our
investigation it involved a familiarisation testing protocol so that all participants from both
creatine and placebo group had the necessary experience.

13. Glaister et al. (2006) suggests that the availability of creatine in the skeletal muscle will not
influence the onset of fatigue on repeated sprints. The Rate of Perceived Excretion (RPE) is
used for the participants to rate their own intensity on the repeated sprints. RPE is individual
to the participants and therefore will vary. In addition, Oliver (2009) states the RPE has no
significant value when measuring fatigue, due to the ongoing research. Thus to improve
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reliability of fatigue measurements are done through developing a familiarisation protocol.
Conclusion
In summary the study was not significant due to the creatine having no effect on physical
performance. Within the study the limitations that were found were that both males and
females were measured together. Also the sample groups were smaller which affected the
way the results were recorded as both these factors can decrease reliability. Creatine and
placebo substances were taken orally; the substances can have a disadvantage to each group
as each individuals training regimes can be different and can progress quicker than others,
participant’s diet plans differ to each other which can have an unbalance within the results.
Intake of the supplement can have a effect on the study if not taken when required, this in
turn makes the study non reliable if the other participants have been strict with the intake of
the supplement. Further research suggests that athletes are doubtful in the effects of creatine
supplementation on several anaerobic performances as little enhancement is shown (Terjung,
2000). The limitations that are stated should be in place before the study is conducted. These
factors are splitting genders apart as this gives more data to compare results giving a greater
outcome, sample groups to be made bigger as the results will be easier to compare and
stricter guidelines should be in place.
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