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The effect of creatine monohydrate ingestion on anaerobic power indices, muscular strength and body composition

Authors:
Conrad P. Earnest at Texas A&M University
Conrad P. Earnest
Peter G Snell at University of Texas Southwestern Medical Center
Peter G Snell
R Rodriguez
R Rodriguez
R Rodriguez
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Anthony L Almada at Vitargo Global Sciences, Inc.
Anthony L Almada
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Acta Physiol
Scand
1995,
153,
207-209
The effect
of
creatine monohydrate ingestion on
anaerobic power indices, muscular strength and
body
composition
C.
P.
EARNEST,’
P.
G.
SNELL,’
R.
RODRIGUEZ,
A.
L.
ALMADA
and
T.
L.
MITCHELL3
‘Texas Woman’s University, Department
of
Kinesiology,
Denton,
‘The
University
of
Texas Southwestern Medical Center and 3The Cooper Clinic, Dallas, Texas,
USA
Creatine monohydrate (Cr.H20) has been shown to
increase intramuscular phosphocreatine (Harris et
a/.
1992) as well as increasing the power output of various
high intensity work tasks (Balsom et
al.
1993,
Greenhaff
et
al.
1993). To the author’s knowledge,
Cr.H20 supplementation in strength trained athletes
has not yet been reported in the literature. Therefore,
this study investigated the influence of Cr.H20
supplementation on muscular power and strength
indices in
10
experienced weight-trained male subjects.
Three series of high intensity, anaerobic type,
muscular workbouts were used. Series one included
three consecutive 30-s Wingate bike tests, interspersed
with 5 min of rest. Peak anaerobic power was denoted
as the greatest power achieved in a given 5-s work
interval. Anaerobic work was defined as the total
amount of work performed in a 30-s period. Series
two utilized
a
one repetition maximum (1 RM) free
weight bench press as a test of muscular strength.
Series three employed complete lifting repetitions at
70% of the bench press
1
RM until fatigue. Lifting
cadence was paced through the use of a metronome set
at a 1-s timing interval (1
s
eccentric, 1
s
concentric)
and fatigue was defined as (1) the inability to complete
one lifting repetition or (2) the inability to maintain
the lifting cadence. Total lifting volume was calculated
as 70% of pre-test 1 RM multiplied by the number of
complete lifting repetitions. Body composition was
measured via hydrostatic weighing techniques; a 3-
day recall was used to assess dietary differences
between groups.
All
procedures were approved by the
Human Subjects Review Board of Texas Woman’s
University, Denton, Texas.
Received 19 September 1994, accepted 13 October
Key
words
:
anaerobic power, body composition,
Correspondence
:
Conrad
P.
Earnest, 7855 Willow
1994.
creatine, muscular strength.
Hill Court
-
Ste. 233, Dallas, TX 75230, USA.
Subjects received, in
a
double blind fashion, either
a glucose placebo or Cr.H20 supplement (Phosphagen,
Experimental and Applied Sciences Inc., Pacific
Grove, CA, USA) as has previously been shown to be
successful (Harris et
al.
1992, Greenhaff
et
al.
1993).
After 14 days of supplementation, each subject was re-
tested
on
the Wingate bike tests. Re-testing for the
weight lifting and anthropometric parameters took
place after 28 days of supplementation. An
ANOVA
for
repeated measures was utilized
to
assess differences
within the Wingate test groups. If statistical signifi-
cance was found,
a
Newman-Keuls post-hoc analysis
was applied.
A
paired dependent t-test was used to
determine differences associated with bench press
1
RM,
total lifting volume and anthropometric
measures. An independent t-test was used to de-
termine differences in nutritional/energy intake.
Statistical significance was set at
P
6
0.05. All values
are listed as pre- vs. post-test and mean
(&
SD).
Eight subjects completed the experimental protocol.
Age was 29.5
f
3.6 and 31.8
f
2.2 years, training
experience was 10.8f3.2 and 11.1 f2.4 years and
percentage of body fat was 10.1
f
3.7 and 9.4f4.6 for
the Cr.H20 and placebo groups, respectively. Within
the Cr.H20 group
(n
=
4), total anaerobic work for
the Wingate tests was significantly higher during all
post-test trials (P
<
0.05). These increases were 13%
for Wingate test 1,
18%
for Wingate test 2 and 18%
for Wingate test 3.
No
changes were noted in the
placebo group
(n
=
4, Table
1).
Greater total an-
aerobic work resulted from the Cr.H20 subject’s
ability to achieve and maintain higher levels of
anaerobic power consistently over each
5-s
time
interval, with statistical significance being apparent
for several 5-s power intervals during the three trials
(data not shown).
Bench press 1 RM increased 6% in the Cr.H20
group (P
<
0.05). When corrected for body weight no
differences were noted because of a significant increase
in body weight within the Cr.H20 group. Total lifting
207
208
C.
P.
Earnest
et
al.
Table
1.
Anaerobic indices values for Cr.H20 and placebo groups. Values are mean and SD
("P
<
0.05,
t
P
<
0.01, and
1
P
<
0.001)
~ ~~ ~~ ~~~~ ~~~ ~
Creatine Placebo
Anaerobic indices Pre Post Pre Post
30-s Wingate bike tests
1 (kJ)
2
(kJ)
3 (kJ)
Bench press 1 RM
Absolute (kg)
Relative (kg kg-')
Lifting repetitions (70% 1
RM)
Total lifting volume
Absolute (kg)
Relative (kg kg-')
22.65 (3.0)
20.40 (2.0)
18.54 (1.0)
126.4
(20.5)
1.5
(0.1)
11.5 (0.8)
1017.7 (93.5)
11.7 (0.7)
25.98 (4.0)*
24.49 (3.0)*
22.73
(2.0)*
134.6 (18.9)*
1.5 (0.1)
15.5
(I.5)t
1459.0 (122.3)f
16.5 (0.9)f
23.48 (1.0)
21.15 (2.0)
119.1 (13.0)
1.4
(0.1)
11.7 (1.8)
975.1 (120.9)
11.8 (1.2)
22.08 (2.0) 23.51 (1.0)
22.32 (2.0)
21.4 (2.0)
116.2 (15.0)
1.4 (0.1)
11.7
(0.8)
951.7 (132.0)
11.5 (1.5)
volume was significantly higher within the Cr.H20
group, whether expressed in absolute terms (26%,
P
<
0.01) or relative terms (29%,
P
<
0.001). In-
creases in total lifting volume were associated with the
ability
of
the Cr.H20 group to perform 26% more
lifting repetitions
(P
<
0.01, Table 1). Body com-
position data indicated a significant increase in body
weight (86.5+ 13.7 vs. 88.2+ 14.1 kg,
P
<
0.05),
as
well as
a
non-significant increase
in
calculated fat free
mass (77.6
f
10.8 vs. 79.2
f
11.6 kg,
P
=
0.054) for
the Cr.H20 group.
No
changes in body weight
(82.6f 2.2 vs. 82.5 1.8 kg) or fat free mass (74.9
f
6.6
vs. 74.4 6.2 kg) were noted for the placebo group. In
addition, no significant differences were noted for
percentage of body fat in either group. These
observations were noted in spite of a significantly
lower daily energy intake (10031 1458 vs.
14650+ 1234 kJ;
P
<
0.01), carbohydrate intake
(5918f860 vs. 7315+617
kJ;
P
<
0.05),
and fat
intake (1204+175 vs. 4354+368 kJ;
P
<
0.05) for
the Cr.H+l vs. placebo groups, respectively.
The observed higher work outputs in the Cr.H20
group were consistent with increases in intramuscular
phosphocreatine stores as noted previously (Harris
et
al.
1992), increased ATP cycling through an attenuated
reduction in ATP with repeated work tasks (Greenhaff
et
al.
1994 b), and an increased rate of phosphocreatine
resynthesis during recovery periods (Greenhaff
et
al.
1994a). What is not clear is the associated gain in body
weight observed in our study as well as those of others
(Balsom
et
al.
1993, Greenhaff
et
al.
1994a). We are
the first group to show that: (1) Cr.H20 supplemen-
tation improves strength training parameters and (2)
that the associated weight gain may be related to an
increase in fat free mass as determined through
hydrostatic weighing techniques.
In
addition, because
weight lifting tasks are typically performed
at
sub-
maximal 1 RM levels during training, the ability
of
the Cr.H20 group to perform a greater total lifting
volume, both in absolute and relative terms, demon-
strates the efficacy of Cr.H20 as an ergogenic aid.
In
turn, the ability
to
perform greater muscular work,
per given work task, provides
a
greater muscular
overload that may promote an increased adaptive
response
in
muscular structure and function.
This
adaptation may account for the observed increase
in
bench press 1 RM, body weight and fat free mass.
Whether or not Cr.H20
per
se,
is directly responsible
for this increase in body weight has yet to be
determined.
We thank Christopher B. Scott
of
the Dallas Heart
Group for his help in the preparation of this
manuscript. This study was supported by
a
grant
from Experimental and Applied Sciences, Inc. Pacific
Grove, CA, USA.
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... Long-term studies (8-140 days) have demonstrated that creatine supplementation can increase total body mass and fatfree mass (7,18,44,46,47). 4) then suggested that the increased diameters may occur in response to an increased myofibular protein-synthesis rate. ...
... In fact, Flisinska-Bojanowska (22) has recently demonstrated that the coupling of creatine supplementation with electrostimulated muscular contractions leads to an increased myofibular protein content in rat muscle. Several studies have also shown that creatine supplementation and resistance-training programs have led to increases in lean body mass (7,18,44,46,47). Another explanation for these findings that is also gaining some popularity is that long-term supplementation allows subjects to train harder and therefore stimulates muscle hypertrophy to a greater extent (18,65). ...
... Several studies have also shown that creatine supplementation and resistance-training programs have led to increases in lean body mass (7,18,44,46,47). Another explanation for these findings that is also gaining some popularity is that long-term supplementation allows subjects to train harder and therefore stimulates muscle hypertrophy to a greater extent (18,65). ...
View
... Previous studies have demonstrated that the muscle store of total creatine (PCr + creatine) can increase by about 10-20% after oral creatine supplementation [13]. Creatine supplementation was shown to increase performance during high intensity exercise in some studies [14][15][16] but not in others [17,18]. ...
... Post -exercise hypoxanthine [16] and plasma NH3 [15] were reduced following creatine supplementation even though there was an increase in work performed. These findings support the hypothesis that limitations to energy supply are a major cause of fatigue during high intensity exercise. ...
Metabolic and hormonal factors influencing high intensity exercise, recovery, and fatigue
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The purpose of the paper is to consider the metabolic mechanisms contributing to high intensity exercise performance, recovery, and fatigue. A further purpose is also to consider the total stress response to exercise by outlining the catecholamine responses to exercise performance
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... Additionally, reports in the media that several British Olympians used creatine during the 1992 Olympics piqued interest in the ergogenic value of creatine supplementation and its use in dietary supplements. About the same time, Earnest and colleagues [75] and Kreider and coworkers [76][77][78][79] demonstrated that creatine supplementation during training could augment gains in strength, power, and lean mass. This was followed by seminal studies by Volek and colleagues [80] and Willoughby et al. [81,82], which showed that gains in weight were attributed to gains in lean mass. ...
Safety of creatine supplementation: analysis of the prevalence of reported side effects in clinical trials and adverse event reports
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Full-text available
Individual studies have indicated that creatine supplementation is generally well tolerated and not associated with clinically significant side effects. Nevertheless, anecdotal reports about side effects persist primarily from popular and social media and on the Internet. This study evaluated side effects reported from 685 human clinical trials on creatine supplementation, worldwide adverse event report (AER) databases, and performed a social media sentiment analysis. The presence of side effects (No, Yes) in studies was evaluated using chi-squared analysis. The frequency of side effects among study participants was evaluated using a multivariate analysis of variance. A total of 13,452 participants in 652 studies ingested placebos (PLA), while 12,839 participants in 685 studies consumed creatine (Cr). Nearly all studies (95%) provided CrM at an average dose of 0.166 [0.159, 0.173] g/kg/d (about 12.5 g/d) for 64.7 [52.0, 77.3] days in studies lasting up to 14 yrs. Side effects were reported in 13.2% of studies in the PLA groups and 13.7% of studies in the Cr-supplemented groups, with no significant differences observed between the groups (p = 0.776). There was a slightly higher percentage of studies reporting gastrointestinal (GI) issues (PLA 4.3%, Cr 4.9%, p < 0.001) and muscle cramping/pain (PLA 0.9%, Cr 2.9%, p = 0.008) with Cr supplementation, but not when the total number of participants in these studies was evaluated (muscle cramping/pain: PLA 0.07%, Cr 0.52%, p = 0.085; GI issues: PLA 4.05%, Cr 5.51%, p = 0.820). Additionally, there was no significant multivariate difference among the 49 side effects evaluated (p = 0.340), no significant difference in the total frequency of side effects reported among participants (PLA 4.21%, Cr 4.60%, p = 0.828), and no significant differences in any of the other side effect evaluated that included markers of renal function and health. The percentage prevalence of side effects was small, with differences between groups generally within ± 0.5%. Analysis of 28.4 million AERs revealed that the mention of Cr was rare (0.00072%), 46.3% of CAERS had no Cr in the products listed, and 63% of AERs with Cr in the product involved the use of other types of Cr or ingestion with other supplements or drugs. The overall sentiment analysis was neutral about perceptions of Cr, although those with strong perceptions about Cr were slightly more negative. Results demonstrate that Cr supplementation does not increase the prevalence or frequency of side effects when compared to participants ingesting PLA. Therefore, claims that Cr supplementation increases the risk of side effects are unfounded.
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... Although Cr supplementation has been shown to increase body mass in various sports [48][49][50][51][52][53][54][55][56][57][58], our metaanalysis of the effects of Cr on body composition in swimmers found no significant changes in body mass and lean body mass with Cr supplementation (Fig. 5). These findings are consistent with previous research [18,19]. ...
Effects of Creatine Supplementation on the Performance, Physiological Response, and Body Composition Among Swimmers: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
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Full-text available
  • Oct 2024
Background Although recent studies have increasingly focused on examining the potential benefits of creatine supplementation to improve performance in swimming events, the impact of creatine supplementation on swimming performance remains a topic of debate and controversy. A comprehensive meta-analytical review was undertaken to evaluate the effects of creatine supplementation on the performance, physiological response, and body composition among swimmers. Methods The research methodology adhered strictly to the guidelines outlined by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). A comprehensive search was conducted across six databases (Cochrane Library, Web of Science, Scopus, Embase, PubMed, and SPORTDiscus) until March 23, 2024. Eligible studies that investigated the impact of creatine supplementation on swimming time, physiological parameters, and body composition in swimmers were included. For the meta-analysis, a random-effects model was employed to determine the collective effect and assess variations across distinct subgroups defined by swimming time, physiological metrics, and body composition. Meta-regression analysis was conducted on datasets comprising ten or more studies. Standardized mean differences (SMD) along with their corresponding 95% confidence intervals (CI) were calculated. To evaluate the methodological rigor of the included studies, the Physiotherapy Evidence Database (PEDro) scale was utilized. Results The systematic review included seventeen studies with a total of 361 subjects. No significant differences were observed in the overall effect during single sprint swimming (SMD: -0.05, 95% CI: -0.26, 0.15; p = 0.61), repeated interval swimming (SMD: -0.11; 95% CI: -0.46, 0.25; p = 0.56), physiological response (SMD: 0.04, 95% CI: -0.16, 0.23; p = 0.71), and body composition (SMD: 0.18; 95% CI: -0.05, 0.41; p = 0.12) between creatine and placebo groups. Conclusions Creatine supplementation exhibited ineffectiveness in enhancing the performance, physiological response, and body composition among swimmers.
View
... This study also reported a decrease in muscle lactate, a finding not supported by other studies that measured lactate. [13][14][15][16][17][18][19][20][21][22] Creatine supplementation and kidney function ...
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... 52 Earnest et al observed a nonsignificant increase in FFM and no change in body fat in their subjects who ingested creatine. 53 These findings suggest that intramyofibrillar water retention may account for most of the increases in FFM. 54 Research on the effects of creatine supplementation on RHR is limited, and the available evidence is not entirely consistent. ...
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Background Creatine is a nutritional supplement commonly used to increase strength performance and muscle mass, but its effects on female wrestlers are still unclear and equivocal. The purpose of the present study is to investigate the efficacy of short-term creatine monohydrate supplementation combined with strength training on the physical fitness characteristics and muscle hypertrophy in junior women wrestlers. Methodology Eighteen women wrestlers (age = 18.7 ± 0.9 years, body mass index = 21.4 ± 2.5 kg/m2) participated in this research. Participants were randomly divided into three groups: Experimental Group 1—EXP1: (training with creatine supplementation), Experimental Group 2—EXP2: (training without creatine supplementation), and Control group (without training or creatine supplementation). Strength training was performed for 6 weeks, four sessions per week, with a training intensity ranging from 65 to 75% of the maximal heart rate reserve and one-repetition maximum. EXP1 was supplemented with 10 g creatine during training days. Various physical fitness characteristics and muscle hypertrophy variables were collected at three time points (pretest, midtest, and posttest). Results A number of variables were significantly improved in the EXP1 after 6 weeks (weight, body mass index, one-repetition maximum, agility, muscular power, and hypertrophy) but not in the EXP2 and control groups. Conclusion Short-term creatine supplementation, in conjunction with strength training, emerges as a highly effective approach for enhancing hypertrophy and boosting physical fitness factors in female wrestlers. Therefore, it is recommended that junior wrestlers individuals supplement with creatine during their strength training routines.
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... This study also reported a decrease in muscle lactate, a finding not supported by other studies that measured lactate. [13][14][15][16][17][18][19][20][21][22] Creatine supplementation and kidney function ...
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... Previous research into the effects of short-term creatine supplementation has been relatively mixed, with some studies showing improvements in muscular performance [39][40][41][42][43][44][45][46][47] and others showing no effect [48][49][50]. The ergogenic effects of creatine are hypothesized to be most relevant in activities that are high intensity and of short duration, where the ATP-PC system is the predominant energy system and supplementation allows for quicker regeneration of ATP to enhance performance. ...
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Maximal Number of Repetitions at Percentages of the One Repetition Maximum: A Meta-Regression and Moderator Analysis of Sex, Age, Training Status, and Exercise
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Creatine supplementation and dynamic high‐intensity intermittent exercise
Article
Full-text available
  • Jan 2007
  • SCAND J MED SCI SPOR
Two intermittent high-intensity exercise protocols were performed before and after the administration of either creatine or a placebo, and performance characteristics and selected physiological responses were studied. Each exercise protocol consisted of 10 6-s bouts of high-intensity cycling at 2 exercise intensities (130 rev/min [EX130]: ∼820 W and 140 rev/min [EX140)]: ∼ 880 W) so that in EX130 the same amount of exercise was performed before and after the administration period, whereas an exercise intensity in EX140 was chosen to induce fatigue over the 10 exercise bouts. Sixteen healthy male subjects were randomly assigned to the 2 experimental groups. A double-blind design was used in this study. There were no significant changes in the placebo group for any of the measured parameters. Performance towards the end of each exercise bout in EX140 was enhanced following creatine supplementation, as shown by a smaller decline in work output from baseline along the 10 trials. Although more work was performed in EX140, after vs before the administration period, blood lactate accumulation decreased (mean and SEM), from 10.8 (0.5) to 9.1 (0.8) mmol·l−1 and plasma accumulation of hypoxanthine decreased from 21.1 (0.4) to 16.7 (0.8) μmol·l−1, but there was no change in oxygen uptake measured during 3 exercise and recovery periods [3.18 (0–1) vs 3.14 (0.1) l·min−1]. In EX130 blood lactate accumulation decreased, from 7.0 (0.5) to 5.1 (0.5) mmol·l−1, and oxygen uptake was also lower, decreasing from 2.84 (0.1) to 2.78 (0.1) l·min−1. A significant increase in body mass (11 kg: range 0.3 to 2.5 kg) was found in the creatine group. The mechanism responsible for the improved performance with creatine supplementation are postulated to be both a higher initial creatine phosphate content availability and an increased rate of creatine phosphate resynthesis during recovery periods. The lower blood lactate and hypoxanthine accumulation can also be explained by these mechanisms.
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Evaluation of Creatine in resting and exercised muscle of normal subjects by Creatine supplementation
Article
  • Oct 1992
1. The present study was undertaken to test whether creatine given as a supplement to normal subjects was absorbed, and if continued resulted in an increase in the total creatine pool in muscle. An additional effect of exercise upon uptake into muscle was also investigated. 2. Low doses (1 g of creatine monohydrate or less in water) produced only a modest rise in the plasma creatine concentration, whereas 5 g resulted in a mean peak after 1 h of 795 (sd 104) μmol/l in three subjects weighing 76–87 kg. Repeated dosing with 5 g every 2 h sustained the plasma concentration at around 1000 μmol/l. A single 5 g dose corresponds to the creatine content of 1.1 kg of fresh, uncooked steak. 3. Supplementation with 5 g of creatine monohydrate, four or six times a day for 2 or more days resulted in a significant increase in the total creatine content of the quadriceps femoris muscle measured in 17 subjects. This was greatest in subjects with a low initial total creatine content and the effect was to raise the content in these subjects closer to the upper limit of the normal range. In some the increase was as much as 50%. 4. Uptake into muscle was greatest during the first 2 days of supplementation accounting for 32% of the dose administered in three subjects receiving 6 × 5 g of creatine monohydrate/day. In these subjects renal excretion was 40, 61 and 68% of the creatine dose over the first 3 days. Approximately 20% or more of the creatine taken up was measured as phosphocreatine. No changes were apparent in the muscle ATP content. 5. No side effects of creatine supplementation were noted. 6. One hour of hard exercise per day using one leg augmented the increase in the total creatine content of the exercised leg, but had no effect in the collateral. In these subjects the mean total creatine content increased from 118.1 (sd 3.0) mmol/kg dry muscle before supplementation to 148.5 (sd 5.2) in the control leg, and to 162.2 (sd 12.5) in the exercised leg. Supplementation and exercise resulted in a total creatine content in one subject of 182.8 mmol/kg dry muscle, of which 112.0 mmol/kg dry muscle was in the form of phosphocreatine.
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Effect of oral Creatine supplementation on skeletal muscle phosphocreatine resynthesis
Article
  • Jun 1994
  • Am J Physiol
Biopsy samples were obtained from the vastus lateralis muscle of eight subjects after 0, 20, 60, and 120 s of recovery from intense electrically evoked isometric contraction. Later (10 days), the same procedures were performed using the other leg, but subjects ingested 20 g creatine (Cr)/day for the preceding 5 days. Muscle ATP, phosphocreatine (PCr), free Cr, and lactate concentrations were measured, and total Cr was calculated as the sum of PCr and free Cr concentrations. In five of the eight subjects, Cr ingestion substantially increased muscle total Cr concentration (mean 29 +/- 3 mmol/kg dry matter, 25 +/- 3%; range 19-35 mmol/kg dry matter, 15-32%) and PCr resynthesis during recovery (mean 19 +/- 4 mmol/kg dry matter, 35 +/- 6%; range 11-28 mmol/kg dry matter, 23-53%). In the remaining three subjects, Cr ingestion had little effect on muscle total Cr concentration, producing increases of 8-9 mmol/kg dry matter (5-7%), and did not increase PCr resynthesis. The data suggest that a dietary-induced increase in muscle total Cr concentration can increase PCr resynthesis during the 2nd min of recovery from intense contraction.
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Influence of Oral Creatine Supplementation of Muscle Torque during Repeated Bouts of Maximal Voluntary Exercise in Man
Article
  • May 1993
1. The present experiment was undertaken to investigate the influence of oral creatine supplementation, shown previously to increase the total creatine content of human skeletal muscle (Harris RC, Soderlund K, Hultman E. Clin Sci 1992; 83: 367–74), on skeletal muscle isokinetic torque and the accumulation of plasma ammonia and blood lactate during five bouts of maximal exercise. 2. Twelve subjects undertook five bouts of 30 maximal voluntary isokinetic contractions, interspersed with 1 min recovery periods, before and after 5 days of placebo (4 × 6 g of glucose/day, n = 6) or creatine (4 × 5 g of creatine plus 1 g of glucose/day, n = 6) oral supplementation. Muscle torque production and plasma ammonia and blood lactate accumulation were measured during and after exercise on each treatment 3. No difference was seen when comparing muscle peak torque production during exercise before and after placebo ingestion. After creatine ingestion, muscle peak torque production was greater in all subjects during the final 10 contractions of exercise bout 1 (P <0.05), throughout the whole of exercise bouts 2 (P <0.01), 3 (P <0.05) and 4 (P = 0.057) and during contractions 11–20 of the final exercise bout (P <0.05), when compared with the corresponding measurements made before creatine ingestion. Plasma ammonia accumulation was lower during and after exercise after creatine ingestion. No differences were found when comparing blood lactate levels. 4. There is evidence to suggest that the decrease in the degree of muscle torque loss after dietary creatine supplementation may be a consequence of a creatine-induced acceleration of skeletal muscle phosphocreatine resynthesis. It is postulated that an increased availability of phosphocreatine would maintain better the required rate of ATP demand during contraction. This is supported by the observed lower accumulation of plasma ammonia during exercise after creatine ingestion.
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The effect of oral creatine supplementation on skeletal muscle ATP
  • Jan 1994
  • P L Greenhaff
  • D Constantin-Teodosiu
  • A Casey
  • E Hultman
GREENHAFF, P.L., CONSTANTIN-TEODOSIU, D., CASEY, A. & HULTMAN, E. 1994b. The effect of oral creatine supplementation on skeletal muscle ATP
Effect of oral creatine supdegradation during repeated bouts of maximal voluntary exercise in man
  • Jan 1994
  • P L Greenhaff
  • K Bodin
  • K Soderlund
  • Hultman
GREENHAFF, P.L., BODIN, K., SODERLUND, K. & HULTMAN. 1994a. Effect of oral creatine supdegradation during repeated bouts of maximal voluntary exercise in man. 3 Physiol467, 84P.