Oral Creatine Research Articles

Efficacy and safety profile of oral creatine monohydrate in add-on to cognitive-behavioural therapy in depression: An 8-week pilot, double-blind, randomised, placebo-controlled feasibility and exploratory trial in an under-resourced area

Pre-clinical and clinical evidence proposes that creatine monohydrate, an affordable nutraceutical, could be a useful adjunct to conventional antidepressant treatments. In this pilot feasibility and exploratory study, we investigate the 8-week effects of creatine in addition to cognitive-behavioural therapy (CBT) versus placebo plus CBT in depression. For the primary efficacy outcome of change in Patient Health Questionnaire-9 depression score at study endpoint, we used mixed-model repeated measures analysis of covariance. Logistic regressions were employed to assess acceptability (any-cause dropouts), tolerability (dropouts for adverse events), and safety (patients experiencing one or more adverse events). We calculated effect sizes adjusted for age, sex, and baseline depression score. One-hundred participants (50 females, mean age= 30.4 ± 7.4 years) with depression (mean PHQ-9 = 17.6 ± 6.3) were randomised to either creatine+CBT (N = 50) or placebo+CBT (N = 50). At 8 weeks, PHQ-9 scores were lower in both study arms, but significantly more so in participants taking creatine (mean difference= -5.12). Treatment discontinuations due to any cause and to adverse events, and proportion of participants with at least one adverse event were comparable between study arms. This hypothesis-generating trial suggests that creatine could be a useful and safe supplement to CBT for depression. Longer and larger clinical trials are warranted.

Estimating the dosage and feasibility of intranasal administration of creatine.

Creatine dysregulation is present in many psychiatric and neurocognitive conditions, supporting the notion that oral creatine supplementation could constitute a viable treatment for conditions such as dementia, depression, and concussion. We recently proposed an intranasal route of administration (ROA) of creatine as a means of efficiently dosing creatine to achieve absorption across the blood brain barrier while targeting preferential delivery to the brain. Indeed, a subsequent murine study supports that creatine can be absorbed via the nasal ROA. The objective of this project is to refine this ROA and estimate appropriate dosage for research trials. The amount of creatine needed to directly supply the brain is but a small portion of the dose that is administered orally for whole-body saturation. A single dose of creatine is typically 5 g, which results in a calculated blood concentration of 80 mg/dL based upon average adult blood volume. Evidence suggests this is sufficient to raise brain creatine levels. Given the adult brain blood volume of 100‒130 mL, we estimate that a minimum of 80 mg of nasally-administered creatine would need to pass from the nasal cavity across the blood-brain barrier. Even if the nasal columnar epithelium or mucus were to pose a barrier, doubling or tripling the dose would still represent a relatively modest amount of nasally-delivered creatine (e.g., 160‒240 mg) in solution. We predict that the amount of nasally-administered creatine to theoretically raise brain blood concentration to a therapeutic level would be modest and practical.

Intranasal creatine administration increases brain creatine level and improves Barnes maze performance in rats

While skeletal muscle creatine levels can be enhanced by exogenous creatine supplementation, the elevation of brain creatine levels with oral creatine administration remains a challenge due to a lack of effective transportation of creatine through the blood-brain barrier. Intranasal administration can bypass the blood-brain barrier and deliver drugs directly to the brain. The purpose of this study was to assess the effect of intranasal administration of creatine on brain creatine level and cognitive performance. Rats were randomly assigned into three groups intranasal administration group, oral administration group, and control group. The intranasal group exhibited fewer errors and shorter primary latency compared to the control and oral groups, respectively, during the acquisition phase of the Barnes maze. The intranasal group spent a higher percentage of time in the target quadrant during the probe trial compared to the control group. Biochemical measurements showed that the concentration of creatine in the olfactory bulbs, medial prefrontal cortex, and hippocampus of the rats in the intranasal group was higher than in the oral, and control groups. These results indicate that intranasal administration of creatine hydrochloride increases the creatine level in the rat’s brain’s and improves their performance in the Barnes maze.

Novel guanidinoacetate methyltransferase (GAMT) mutation associated with cerebral creatine deficiency syndrome in a Syrian child: a case report.

A 2.5-year-old boy presented to the paediatric neurology clinic with evidence of neurodevelopmental delays and intellectual disabilities. Recurrent eye blinking, generalized non-motor (absence) seizures, hyperactivity, and poor eye contact were revealed in the neurological examination. Some athetoid and dystonic movements were noticed. His electroencephalography (EEG) was very disturbed because of generalized spike-wave and slow-wave discharges. Based on these findings antiepileptic drugs were administered. His seizures slightly improved, but then relapsed with myoclonic and drop attacks. After 6 years of unbeneficial treatment, a genetic test was required. Whole-exome sequencing was conducted and identified a novel homozygous GAMT variant (NM_138924.2:c.391+5G>C). Treatment with oral creatine supplementation, ornithine, and sodium benzoate was administered. After 1.7 years of follow-up, the child was almost seizure-free with a remarkable reduction of epileptic activity on EEG. He demonstrated good-but not complete-behavioural and motor improvement due to delayed diagnosis and treatment. GAMT deficiency should be considered in differential diagnoses in children with neurodevelopmental regression along with drug-refractory epilepsy. A special concern is needed in Syria for such genetic disorders; regarding the high prevalence of consanguinity. Whole-exome sequencing and genetic analysis can be used to diagnose this disorder. We reported a novel GAMT variant to extend its mutation spectrum and provide an additional molecular marker for the definitive diagnosis of GAMT deficiency patients and prenatal diagnosis in the affected families.

Letter to the Editor: Double-counting due to inadequate statistics leads to false-positive findings in "Effects of creatine supplementation on memory in healthy individuals: a systematic review and meta-analysis of randomized controlled trials".

Prokopidis et al have conducted a meta-analysis of randomized, placebo-controlled clinical trials to assess the effects of oral creatine supplementation on memory performance of healthy individuals. However, concerns were raised regarding the validity of their statistical analyses, which may have led to misleading conclusions. In this letter, we describe the statistical issue at hand and its potential implications.

Gene therapy for guanidinoacetate methyltransferase deficiency restores cerebral and myocardial creatine while resolving behavioral abnormalities

Creatine deficiency disorders are inborn errors of creatine metabolism, an energy homeostasis molecule. One of these, guanidinoacetate N-methyltransferase (GAMT) deficiency, has clinical characteristics that include features of autism, self-mutilation, intellectual disability, and seizures, with approximately 40% having a disorder of movement; failure to thrive can also be a component. Along with low creatine levels, guanidinoacetic acid (GAA) toxicity has been implicated in the pathophysiology of the disorder. Present-day therapy with oral creatine to control GAA lacks efficacy; seizures can persist. Dietary management and pharmacological ornithine treatment are challenging. Using an AAV-based gene therapy approach to express human codon-optimized GAMT in hepatocytes, in situ hybridization, and immunostaining, we demonstrated pan-hepatic GAMT expression. Serial collection of blood demonstrated a marked early and sustained reduction of GAA with normalization of plasma creatine; urinary GAA levels also markedly declined. The terminal time point demonstrated marked improvement in cerebral and myocardial creatine levels. In conjunction with the biochemical findings, treated mice gained weight to nearly match their wild-type littermates, while behavioral studies demonstrated resolution of abnormalities; PET-CT imaging demonstrated improvement in brain metabolism. In conclusion, a gene therapy approach can result in long-term normalization of GAA with increased creatine in guanidinoacetate N-methyltransferase deficiency and at the same time resolves the behavioral phenotype in a murine model of the disorder. These findings have important implications for the development of a new therapy for this abnormality of creatine metabolism.

Effects of Oral Creatine Supplementation on Power Output during Repeated Treadmill Sprinting.

The aim of the present study was to examine the effects of creatine (Cr) supplementation on power output during repeated sprints on a non-motorized treadmill. Sixteen recreationally active males volunteered for this study (age 25.5 ± 4.8 y, height 179 ± 5 cm, body mass 74.8 ± 6.8 kg). All participants received placebo supplementation (75 mg of glucose·kg−1·day−1) for 5 days and then performed a baseline repeated sprints test (6 × 10 s sprints on a non-motorised treadmill). Thereafter, they were randomly assigned into a Cr (75 mg of Cr monohydrate·kg−1·day−1) or placebo supplementation, as above, and the repeated sprints test was repeated. After Cr supplementation, body mass was increased by 0.99 ± 0.83 kg (p = 0.007), peak power output and peak running speed remained unchanged throughout the test in both groups, while the mean power output and mean running speed during the last 5 s of the sprints increased by 4.5% (p = 0.005) and 4.2% to 7.0%, respectively, during the last three sprints (p = 0.005 to 0.001). The reduction in speed within each sprint was also blunted by 16.2% (p = 0.003) following Cr supplementation. Plasma ammonia decreased by 20.1% (p = 0.037) after Cr supplementation, despite the increase in performance. VO2 and blood lactate during the repeated sprints test remained unchanged after supplementation, suggesting no alteration of aerobic or glycolytic contribution to adenosine triphosphate production. In conclusion, Cr supplementation improved the mean power and speed in the second half of a repeated sprint running protocol, despite the increased body mass. This improvement was due to the higher power output and running speed in the last 5 s of each 10 s sprint.

Creatine Supplementation Upregulates mTORC1 Signaling and Markers of Synaptic Plasticity in the Dentate Gyrus While Ameliorating LPS-Induced Cognitive Impairment in Female Rats.

Mild cognitive impairment (MCI) designates the boundary area between cognitive function in natural aging and dementia, and this is viewed as a therapeutic window to prevent the occurrence of dementia. The current study investigated the neurocognitive effects of oral creatine (Cr) supplementation in young female Wistar rats that received intracerebroventricular injections of lipopolysaccharide (LPS) to mimic MCI. Neuromolecular changes within the dentate gyrus were analyzed following behavioral testing. We also investigated both neurocognitive and neuromolecular changes following Cr supplementation in the absence of LPS in young female Wistar rats to further investigate mechanisms. Interestingly, based on trial 2 of Barnes maze test, Cr supplementation ameliorated spatial learning and memory deficit induced by LPS, shown by decreased latency time and errors to reach the escape box (p < 0.0001, n = 12). Cr supplementation also attenuated recognition memory deficit induced by LPS, shown by increased amount of time taken to explore the new object (p = 0.002, n = 12) during novel object recognition testing. Within the dentate gyrus, Cr supplementation in LPS injected rats upregulated mTORC1 signaling (p = 0.026 for mTOR phosphorylation, p = 0.002 for p70S6K phosphorylation, n = 8) as well as the synapsin (p = 0.008) and PSD-95 synaptic proteins (p = 0.015), in comparisons to LPS injected rats. However, Cr supplementation failed to further enhance spatial memory and recognition memory in the absence of LPS. In conclusion, Cr ameliorates LPS-induced cognitive impairment in a rodent MCI model. Mechanistically, these phenotypic effects may, in part, be mitigated via an upregulation of mTORC1 signaling, and an enhancement in synaptogenesis in the dentate gyrus. While preliminary, these findings may inform future research investigating neurocognitive effects of Cr for MCI patients.

체내 크레아틴 민감성 변화가 크레아틴 구강 섭취 시 건강한 여성의 체지방과 근육량의 변화에 미치는 영향

본 연구의 목적은 체내 크레아틴 민감성 변화와 크레아틴 구강 섭취가 여성의 체지방과 근육량의 변화에 미치는 영향을 규명하는 데 있다. K지역 D대학교에 재학중인 대학생 15명의 여성을 대상으로 식이제한군(n=8)과 자유식군(n=7)으로 나누어 총 6주간의 실험에 참여하였다. 실험 기간 중 총 4번의 처치시기(실험시작, 운동시작, 크레아틴 로딩 전, 크레아틴 로딩 후)에 따른 신체조성을 측정하였으며, 실험 시작 2주 후부터 실험 종료 시점까지 총 4주간 주당 2회의 하체 근력 운동(Squat, Leg press, Leg curl, Leg extension, Lunge)을 실시하였다. 모든 대상자는 실험 6주차에서 6일 동안 캡슐로 제공되는 크레아틴을 하루 25g씩 보충 섭취하였다. 분석결과 자유식 그룹에서 실험시작보다 운동시작 시 체지방량의 감소(p<.05)가 나타나기는 하였으나 크레아틴이 함유된 음식을 제한한 식이제한 그룹과 자유식 그룹에서 체중과 제지방량, 체지방량, 근육량 모두가 처치시기에 따른 변화가 나타나지 않았으며(p>.05), 각 처치시기별 그룹 간 비교에 있어서도 차이가 나타나지 않아(p>.05) 크레아틴 민감성 변화와 크레아틴 구강 섭취가 여성의 체지방과 근육량에 영향을 미치지 않았다.

Uso do suplemento de creatina em praticantes de atividades físicas: uma revisão integrativa

Objetivo: Identificar evidências científicas na literatura da eficácia do suplemento de creatina na melhoria da performance dos praticantes de atividades físicas. Métodos: Tratou-se de uma revisão teórica do tipo integrativa, do período de 2015 a 2019, com acesso às bases LILACS, PUBMED e SCIELO. Os critérios para incluir um estudo na revisão foram manuscritos de revistas científicas; qualis B4 e maiores; pesquisas realizadas em humanos; e suplementação exclusivamente oral de creatina. Desse modo, foram selecionados seis artigos para compor o presente trabalho de revisão. Resultados: Quatro dos estudos analisados evidenciaram melhoria no desempenho físico dos praticantes de atividade. Em dois desses quatro, essa melhoria foi estatisticamente significativa. Em outros dois manuscritos, não foi determinado um aumento significativo no desempenho. Considerações finais: A revisão teórica evidenciou que a suplementação de creatina melhora o desempenho dos praticantes de atividades físicas, considerando que em essas estejam envolvidos os esforços de resistência e força muscular.

Elevating the level of hypoxia inducible factor may be a new potential target for the treatment of depression

Hypoxia inducible factor-1 (HIF-1) is a transcriptional factor that regulates gene expressions in response to decreased oxygen levels in the tissue, or hypoxia. HIF-1 exerts protective effects against hypoxia by mediating mitochondrial metabolism and consequently reducing oxidative stress. Recently, increased levels of oxidative stress and abnormal energy metabolism in the brain have been suggested to play essential roles in the pathogenesis of depression. Given that HIF-1 activates creatine metabolism and increases phosphocreatine levels in the intestinal epithelial cells, we assume that HIF-1 may induce similar processes in the brain. Elevated phosphocreatine levels in the brain, as measured by magnetic resonance spectroscopy, were associated with better treatment response to the antidepressants in individuals with depression. In addition, oral creatine supplements, which led to increased phosphocreatine levels in the brain, also enhanced the effects of antidepressants in individuals with depression. As such, we hypothesized that increasing the HIF-1, which potentially facilitates creatine metabolism in the brain, might be a new therapeutic target in depression. With this regard, we suggested that interventions to elevate the HIF-1 levels in the brain, including the intermittent hypoxia conditioning and hyperbaric oxygen therapy, might be considered as new additional treatments for depression.

Vitreous metabolomics profiling of proliferative diabetic retinopathy.

Proliferative diabetic retinopathy (PDR) with retinal neovascularisation (NV) is a leading cause of vision loss. This study identified a set of metabolites that were altered in the vitreous humour of PDR patients compared with non-diabetic control participants. We corroborated changes in vitreous metabolites identified in prior studies and identified novel dysregulated metabolites that may lead to treatment strategies for PDR. We analysed metabolites in vitreous samples from 43 PDR patients and 21 non-diabetic epiretinal membrane control patients from Japan (age 27-80years) via ultra-high-performance liquid chromatography-mass spectrometry. We then investigated the association of a novel metabolite (creatine) with retinal NV in mouse oxygen-induced retinopathy (OIR). Creatine or vehicle was administered from postnatal day (P)12 to P16 (during induced NV) via oral gavage. P17 retinas were quantified for NV and vaso-obliteration. We identified 158 metabolites in vitreous samples that were altered in PDR patients vs control participants. We corroborated increases in pyruvate, lactate, proline and allantoin in PDR, which were identified in prior studies. We also found changes in metabolites not previously identified, including creatine. In human vitreous humour, creatine levels were decreased in PDR patients compared with epiretinal membrane control participants (false-discovery rate <0.001). We validated that lower creatine levels were associated with vascular proliferation in mouse retina in the OIR model (p = 0.027) using retinal metabolomics. Oral creatine supplementation reduced NV compared with vehicle (P12 to P16) in OIR (p = 0.0024). These results suggest that metabolites from vitreous humour may reflect changes in metabolism that can be used to find pathways influencing retinopathy. Creatine supplementation could be useful to suppress NV in PDR. Graphical abstract.

Repeated Application of a Novel Creatine Cream Improves Muscular Peak and Average Power in Male Subjects.

Whinton, AK, Donahoe, K, Gao, R, Thompson, KMA, Aubry, R, Saunders, TJ, Johnston, A, Chilibeck, PD, and Burr, JF. Repeated application of a novel creatine cream improves muscular peak and average power in male subjects. J Strength Cond Res 34(9): 2482-2491, 2020-Using a multicenter, randomized controlled trial, (N = 123, age 23 ± 4 years) we sought to determine whether administration of a novel, topical creatine supplement could improve muscular performance after acute and repeated (7-day) exposure. To study the acute performance enhancing effects of the supplement, subjects completed 5 sets of 15 maximal concentric single-leg knee extensions with and without the application of a low- (low dose [LD]-3.5 ml) or high-dose (high dose [HD]-7 ml) topical creatine cream. After a wash-out period, subjects had one leg randomized to receive either the creatine or placebo cream, with further randomization into an oral creatine or placebo supplement group. Subjects completed 5 sets of 15 maximal concentric single leg knee extensions before and after the supplementation protocol. After acute application, no significant differences in peak power (LD: 252 ± 93 W, HD: 261 ± 100 W, p = 0.21), average power (LD: 172 ± 65 W, HD: 177 ± 69 W, p = 0.78), or fatigue index (LD: 13.4 ± 10.6%, HD: 14 ± 11.9%, p = 0.79) were observed between experimental and placebo creams (peak power: LD: 244 ± 76 W, HD: 267 ± 109 W; average power: LD: 168 ± 57 W, HD: 177 ± 67 W; fatigue index: LD: 12.4 ± 9.6%, HD: 12.8 ± 10.6%) or when controlling for sex. After the 7-day supplementation protocol, a significant increase in average power (creatine: 203 ± 61-220 ± 65 W, placebo: 224 ± 61-214 ± 61 W) and peak power (creatine: 264 ± 73-281 ± 80 W, placebo: 286 ± 79-271 ± 73 W) in the leg receiving creatine cream was observed in male subjects. No differences were observed in female subjects. The topical creatine cream did not enhance measures of muscle performance after acute application, but was able to improve peak and average power in male subjects after 7 consecutive days of application.

Risk of Adverse Outcomes in Females Taking Oral Creatine Monohydrate: A Systematic Review and Meta-Analysis.

Creatine Monohydrate (CrM) is a dietary supplement routinely used as an ergogenic aid for sport and training, and as a potential therapeutic aid to augment different disease processes. Despite its increased use in recent years, studies reporting potential adverse outcomes of CrM have been mostly derived from male or mixed sex populations. A systematic search was conducted, which included female participants on CrM, where adverse outcomes were reported, with meta-analysis performed where appropriate. Six hundred and fifty-six studies were identified where creatine supplementation was the primary intervention; fifty-eight were female only studies (9%). Twenty-nine studies monitored for adverse outcomes, with 951 participants. There were no deaths or serious adverse outcomes reported. There were no significant differences in total adverse events, (risk ratio (RR) 1.24 (95% CI 0.51, 2.98)), gastrointestinal events, (RR 1.09 (95% CI 0.53, 2.24)), or weight gain, (mean difference (MD) 1.24 kg pre-intervention, (95% CI −0.34, 2.82)) to 1.37 kg post-intervention (95% CI −0.50, 3.23)), in CrM supplemented females, when stratified by dosing regimen and subject to meta-analysis. No statistically significant difference was reported in measures of renal or hepatic function. In conclusion, mortality and serious adverse events are not associated with CrM supplementation in females. Nor does the use of creatine supplementation increase the risk of total adverse outcomes, weight gain or renal and hepatic complications in females. However, all future studies of creatine supplementation in females should consider surveillance and comprehensive reporting of adverse outcomes to better inform participants and health professionals involved in future trials.

Enhanced mitochondrial biogenesis is associated with the ameliorative action of creatine supplementation in rat soleus and cardiac muscles.

The current study focused on the effect of creatine supplementation with/without exercise on the expression of genes controlling mitochondrial biogenesis in skeletal and cardiac muscles, as well as its safety profile on the liver and kidney. A total of 40 male Wister rats were included in the present study. Two unexercised groups: The control sedentary group and the sedentary creatine-treated group (n=10) were treated daily with oral creatine (0.5 g/kg per day). Two exercised groups performed swimming exercise training 5 days/week for a period of 5 weeks; The Exercise training group, and exercise training and creatine (0.5 g/kg per day) treated group. After sacrifice, blood samples, cardiac and soleus muscles were collected for assessment of mtDNA copy number, gene expression analysis and nuclear extraction for the assay of PGC-1α. The results of the current study demonstrated that, physical activity with short-term creatine supplementation increased all factors of mitochondrial biogenesis, an effect that is devoid of any kidney or liver adverse effects. Further studies are still required to explore the potential of creatine supplementation in ameliorating mitochondrial diseases, including epilepsy, skeletal and cardiac myopathies, hepatopathies and nephropathies.

Creatine is Neuroprotective to Retinal Neurons In Vitro But Not In Vivo.

To investigate the neuroprotective properties of creatine in the retina using in vitro and in vivo models of injury. Two different rat retinal culture systems (one containing retinal ganglion cells [RGC] and one not) were subjected to either metabolic stress, via treatments with the mitochondrial complex IV inhibitor sodium azide, or excitotoxic stress, via treatment with N-methyl-D-aspartate for 24 hours, in the presence or absence of creatine (0.5, 1.0, and 5.0 mM). Neuronal survival was assessed by immunolabeling for cell-specific antigens. Putative mechanisms of creatine action were investigated in vitro. Expression of creatine kinase (CK) isoenzymes in the rat retina was examined using Western blotting and immunohistochemistry. The effect of oral creatine supplementation (2%, wt/wt) on retinal and blood creatine levels was determined as well as RGC survival in rats treated with N-methyl-D-aspartate (NMDA; 10 nmol) or high IOP-induced ischemia reperfusion. Creatine significantly prevented neuronal death induced by sodium azide and NMDA in both culture systems. Creatine administration did not alter cellular adenosine triphosphate (ATP). Inhibition of CK blocked the protective effect of creatine. Retinal neurons, including RGCs, expressed predominantly mitochondrial CK isoforms, while glial cells expressed exclusively cytoplasmic CKs. In vivo, NMDA and ischemia reperfusion caused substantial loss of RGCs. Creatine supplementation led to elevated blood and retinal levels of this compound but did not significantly augment RGC survival in either model. Creatine increased neuronal survival in retinal cultures; however, no significant protection of RGCs was evident in vivo, despite elevated levels of this compound being present in the retina after oral supplementation.

Oral Creatine Supplementation On Physicaly Active Elderly Women Cognition Improvement

PURPOSE: The aim of this study was to verify if creatine supplementation in conjunction with a community-based exercise program improved cognition in elderly women. METHODS: Twenty elderly women were randomized into 2 groups: creatine (CRE, n=10, age = 71± 6 y; body mass = 67.4± 6.0 kg; height = 166±2 cm) or control (CON, n=10, age = 73±6 y; body mass = 67.4±5.7 kg; height = 164±4 cm). All subjects were active and did not use CM or pro-cognitive drugs before the experiment. CRE group received 2.0 g.kg body mass-1·d-1 of CM for 28 days. CON group received 2,0 g.kg body mass-1.day-1 of dextrosol. Community-based exercises (walking, dancing, calisthenics, stretching) were performed 3x a week with 1 h per session. Cognition was assessed using a battery of five tests: a Visual Reaction Time (VRT) test, a visual GO/NO GO reaction time (GNG) test; a Differentiation task test (DTT), an Eriksen flanker test (EFT), and a Corsi block test (CBT). Subjects completed a familiarization, taking the testing battery on two sessions over nonconsecutive days the week prior to the experiment. The week after familiarization, subjects completed the test battery and initiated supplementation (CRE or CON). After 28 days, they repeated the test battery. Chi-square tests were used to compare groups and sessions for DTT, EFT, and CBT. Repeated measures ANOVA were used to compare VRT and GNG. Significance level was set p≤ 0.05. RESULTS: Significant (p≤ 0.05) pre-post performance increases in GNG, EFT, and CBT were observed in CRE vs. CON (table 1). We did not find difference between moments or groups in VRT (p>0.05) nor DTT (p>0.05). Table 1 - Cognitive tests results *p ≤0.05 difference from other means according to ANOVA. Differing superscripts (a,b) indicate p ≤ 0.05 difference according to Chi-SquareTable 1: Cognitive tests results *p ≤0.05 difference from other means according to ANOVA. Differing superscripts (a,b) indicate p ≤ 0.05 difference according to Chi-SquareCONCLUSIONS: We conclude that 2g·kg-1·day-1 during 28 days of oral CM supplementation improved results in some cognitions tasks in elderly woman.

Effect of oral creatine on anaerobic sports ability of soccer players

Objectives: The objective of this study is to explore the effect of oral creatine on the anaerobic exercise ability of soccer players. Methods: Twenty healthy football players in five football teams were selected as the study participants, and they were randomly divided into the observation group and control group, each of which was 10. The football players in the control group were given glucose at a rate of 5 g/time, and the members of the observation group were given creatine glucose at a rate of 5 g/time and the supplementation of the two groups was 5 g × 4 when they have their meals and before bedtime. During the period, the training of the football players is normal. Moreover, the blood lactic acid and oxygen-free work of the two groups were compared. Results: After having oral creatine, the peak of oxygen-free work of the observation group was significantly increased, which was obviously superior to the control group without oral creatine. The difference was statistically significant (P < 0.05). After having oral creatine, the lactate level of 3 min in the observation group was significantly lower than that in the control group after exercise, and the difference was statistically significant (P < 0.05). Conclusions: After the oral creatine is taken orally, the peak of the oxygen-free work, the explosive force and the action quality of the football player can be improved. Significantly, it can increase the speed of movement fatigue recovery and it is worth popularizing.

Elevation of serum creatinine in a renal transplant patient following oral creatine supplementation.

We report the case of a renal transplant recipient presenting with elevated serum creatinine levels whilst taking oral creatine ethyl ester (CEE), but not creatine monohydrate (CM). Standard investigations for allograft dysfunction, including Doppler ultrasound and renal biopsy, were normal. Serum creatinine normalized following cessation of the supplement. CM is poorly absorbed and does not affect creatinine. In contrast, CEE is converted and absorbed as creatinine, elevating serum levels. In such cases, creatinine is not a valid surrogate for glomerular filtration rate (GFR). Alternate methods of GFR measurement should be considered and a rigorous clinical and drug history taken.

Effects of Oral Creatine Supplementation with Different Doses on the Biochemical Markers of Liver, Kidney and Testis in Swimming Trained Male Rats

Effects of Oral Creatine Supplementation with Different Doses on the Biochemical Markers of Liver, Kidney and Testis in Swimming Trained Male Rats