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Creatine supplementation in exercise, sport, and medicine
... Cr can be endogenously synthesized from amino acids in the kidney and liver, producing about 1-3 g/day in the body [16]. It is a proenergetic, as its major function is to form phosphor-creatine which when acted upon by creatine kinase can transfer the high energy phosphate to ADP creating ATP which provides energy [16,17]. Previous studies have shown that Cr elevates IGF-1 mRNA expression levels in skeletal muscle in adult humans [18,19]. ...
... Additionally, Cr supplementation protects against mitochondrial mutagenesis as well as increases in matrix metalloproteinase-1 in response to UVA [39]. Data from other cell types provided some premise for testing the ability of pro-energetics Cr and NAM to block fibroblast senescence [17,24,25,38,40,41]. In particular, low levels of Cr in disease states including in kidney dialysis patients have been linked to overall poor health [41,42]. ...
Dermal fibroblasts provide structural support by producing collagen and other structural/support proteins beneath the epidermis. Fibroblasts also produce insulin-like growth factor-1 (IGF-1), which binds to the IGF-1 receptors (IGF-1Rs) on keratinocytes to activate signaling pathways that regulate cell proliferation and cellular responses to genotoxic stressors like ultraviolet B radiation. Our group has determined that the lack of IGF-1 expression due to fibroblast senescence in the dermis of geriatric individuals is correlated with an increased incidence of skin cancer. The present studies tested the hypothesis that pro-energetics creatine monohydrate (Cr) and nicotinamide (NAM) can protect normal dermal human fibroblasts (DHF) against experimentally induced senescence. To that end, we used an experimental model of senescence in which primary DHF are treated with hydrogen peroxide (H2O2) in vitro, with senescence measured by staining for beta-galactosidase activity, p21 protein expression, and senescence associated secretory phenotype cytokine mRNA levels. We also determined the effect of H2O2 on IGF-1 mRNA and protein expression. Our studies indicate that pretreatment with Cr or NAM protects DHF from the H2O2-induced cell senescence. Treatment with pro-energetics post-H2O2 had no effect. Moreover, these agents also inhibited reactive oxygen species generation from H2O2 treatment. These studies suggest a potential strategy for protecting fibroblasts in geriatric skin from undergoing stress-induced senescence, which may maintain IGF-1 levels and therefore limit carcinogenesis in epidermal keratinocytes.
... La cantidad total de Cr en el músculo es de 120 mmol/kg de media para personas de 70 kg, pudiendo llegar a haber niveles de 160 mmol/kg en individuos con misma masa corporal [64]. La mayoría de Cr se encuentra en el músculo esquelético (~95%), mientras que el ~5% restante se encuentra en cerebro y testículos [65,66]. Respecto a la Cr en el músculo, esta se divide en fosofocreatina (PCr) y Cr libre, ocupando la PCr dos tercios del total y la Cr libre el tercio restante [62]. ...
... Estructura química y vía bioquímica para la síntesis de Cr [62,66] Sin embargo, la síntesis de Cr no es suficiente para tener los depósitos de Cr normales, ya que el cuerpo necesita entre 1 y 3 gramos de Cr. Aproximadamente, la mitad de la Cr diaria necesaria se obtiene a través de la dieta [68,69]. ...
El monohidrato de creatina (CrM) y el β-hidroxi β-metilbutirato (HMB) son suplementos deportivos ampliamente estudiados. Sin embargo, no está claro cómo actúan cuando se utilizan conjuntamente en el ámbito deportivo. Hay que añadir que la incógnita es todavía mayor, cuando hablamos de un deporte de carácter predominantemente aeróbico como el remo.
Los objetivos de esta tesis han sido: 1) determinar mediante una revisión sistemática la eficacia de mezclar CrM más HMB en comparación con sus efectos aislados sobre el rendimiento deportivo, la composición corporal, los marcadores de daño muscular inducidos por el ejercicio (EIMD) y las hormonas anabólico-catabólicas. 2) determinar la eficacia y el grado de potenciación de 10 semanas de suplementación con CrM más HMB en el rendimiento deportivo, que se midió mediante una prueba incremental en remeros tradicionales de élite masculinos. 3) determinar el efecto y el grado de potenciación de 10 semanas de suplementación con CrM más HMB en los EIMD y hormonas anabólicas/catabólicas.
En base a los objetivos planteados, los principales resultados de la tesis indican que: 1) La combinación de CrM más 3 g/día de HMB durante 1–6 semanas podría producir efectos positivos en el rendimiento deportivo (fuerza y rendimiento anaeróbico) y durante 4 semanas en la composición corporal (aumento de grasa masa libre y disminución de la masa grasa). 2) La ingesta de CrM más HMB durante 10 semanas mostró un efecto sinérgico sobre la potencia aeróbica durante una prueba incremental. 3) La combinación de CrM más HMB presentó un efecto sinérgico sobre la testosterona y la ratio testosterona/cortisol y un efecto antagonista sobre el cortisol en comparación con la suma de la suplementación individual o aislada.
Las conclusiones obtenidas en la presente tesis doctoral indican que la combinación de estos dos suplementos puede ser de gran ayuda para los profesionales que rodean al deportista para mejorar el rendimiento aeróbico y la recuperación.
... Actualmente se conoce que la creatina (ácido metilguanidina-acético) es un ácido orgánico nitrogenado natural o aminoácido proteico natural (Terjung et al., 2000) y uno de los suplementos dietéticos más populares y consumidos por los deportistas y/o atletas en diferentes modalidades (Kreider & Jung, 2011;Kreider et al., 2017), debido a las más de 80 revisiones que reportan beneficios sobre su consumo terapéutico y ergogénico (De Guingand et al.,2020). Se conoce también que el consumo de creatina a modo de suplemento dietético genera un aumento de sus concentraciones a nivel intramuscular y en las reservas de fosfocreatina, mejorando el metabolismo de los fosfágenos (Baker et al., 2010), lo que da como resultante una mejora significativa y valiosa en el rendimiento físico ante actividades de alta intensidad. ...
El futbol es un deporte colectivo, uno de los deportes más populares a lo largo del mundo. Por lo cual, se requiere el aporte de estrategias nutricionales para el óptimo rendimiento del deportista. El objetivo de esta revisión sistemática es analizar y describir a través de la literatura científica los efectos del consumo de creatina en futbolistas. A través de las bases de datos Scopus, WoS, Pubmed y SciELO, se identificaron un total de 6 artículos científicos, que fueron encontrados mediante el uso de las palabras claves “Soccer” OR “Football”, AND “Creatine” AND" physical condition" OR "performance". Se encontraron resultados relacionados con “Dosis de creatina y periodo de intervención”, “Efectos en las vías respiratorias y volumen respiratorio”, “Altura de salto”, “Resistencia aeróbica”, “Potencia anaeróbica”, “Habilidad deportiva”, y “Velocidad y cambios de dirección”. Finalmente, la efectividad del consumo de creatina se encuentra orientado a la presencia de una fase de mantenimiento o a una fase de carga adicionado a una de mantenimiento, permitiendo mejoras en las vías respiratorias, potencia muscular, la velocidad y el rendimiento físico en los futbolistas. Palabras claves: Fútbol; Creatina; Rendimiento; Condición física Abstract. Soccer is a collective sport, one of the most popular sports throughout the world. Therefore, the contribution of nutritional strategies is required for the optimal performance of the athlete. The objective of this systematic review is to analyze and describe through the scientific literature the effects of creatine consumption in soccer players. Through the Scopus, WoS, Pubmed and SciELO databases, a total of 6 scientific articles were identified, which were found using the keywords "Soccer" OR "Football", AND "Creatine" AND "physical condition". " OR "performance". Results related to "Creatine dose and intervention period", "Effects on the respiratory tract and respiratory volume", "Jump height", "Aerobic resistance", "Anaerobic power", "Sportsmanship", and "Speed" were found. and address changes. Finally, the effectiveness of creatine consumption depends on the inclusion of a maintenance phase or not, allowing improvements in muscle power, speed and physical performance in soccer players. Keywords: Soccer; Creatine; Performance; Physical condition
... Creatine was discovered in 1832 in beef muscle by the French chemist Michel Chevreul, and since then it has been extensively studied in different aspects in human and animal biology, being described as a pleotropic molecule (Wyss and Kaddurah-Daouk 2000;Shao and Hathcock 2006;Wallimann et al. 2011). In vertebrate's, most of the creatine is stored primarily in skeletal muscle, while the remining pool of creatine is found in the liver, heart, brain, the retina, macrophages, and spermatozoa (Burger 1919;Meador et al. 1968;Hultman et al. 1996;Wyss and Kaddurah-Daouk 2000;Ipsiroglu et al. 2001;Kreider and Jung 2011). From different experimental approaches, the beneficial effects of supplementing creatine in livestock species (Stahl et al. 2001;Berg and Allee 2001;Berg 2003;Young et al. 2004;Ringel et al. 2007;Young et al. 2007;Carvalho et al. 2013;Janicki and Buzala 2013;Zhang et al. 2014;Wang et al. 2015;Zhang et al. 2017;Dinesh et al. 2018;Li et al. 2018;Ibrahim et al. 2019;Liu et al. 2020;Mao et al. 2022), mammalian models (Stefani et al. 2014;McBreairty et al. 2015) and human (Buford et al. 2007;Tarnopolsky et al. 2007;Kreider et al. 2017) have extensively been explored in the past. ...
Creatine is a popular ergogenic sport supplement used to improve exercise performance and muscle growth in athletes. Further, studies suggest protective effects of creatine in neurodegenerative diseases, type 2 diabetes, osteoarthritis, fibromyalgia, aging and fatty liver disease in humans. Similarly, the versatility of creatine, as a supplement or feed additive, has been evaluated in different animal production systems, including terrestrial livestock, poultry and aquaculture fish species. Some of the observed effects are increased antioxidant activity and flesh quality, improved lipid homeostasis as well as enhanced overall productive performance. Despite creatine being synthesized endogenously, this capacity might be insufficient to adequately cover the creatine needs in fish fed diets formulated with ingredients devoid of this nutrient, notably plant protein feedstuffs. As aquaculture industry moves toward sustainability, removal of creatine-rich dietary ingredients, such as fishmeal, in aquafeeds will likely further increase in coming decades. Thus, under this scenario it might be necessary for dietary supplementation of creatine to support optimal fish productive performance and product quality. This review describes the current knowledge of creatine physiology and metabolism in fish, and highlights possible parallels with metabolism in livestock species, mammalian models and human as well as the benefits obtained from creatine supplementation.
... Creatine (Cr) is a non-protein amino acid endogenously synthesized primarily in the liver and kidneys through several enzyme processes from arginine, glycine, and methionine [1,2]. Creatine is predominantly stored in skeletal muscle (~ 95%), with ~ 66% of intramuscular Cr stored as phosphocreatine (PCr), and the remaining as free Cr [3]. ...
Background
There is robust evidence that creatine monohydrate supplementation can enhance short-term high-intensity exercise in athletes. However, the effect of creatine monohydrate supplementation on aerobic performance and its role during aerobic activities is still controversial.
Objective
The purpose of this systematic review and meta-analysis was to evaluate the supplementation effects of creatine monohydrate on endurance performance in a trained population.
Methods
The search strategy in this systematic review and meta-analysis was designed following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and PubMed/MEDLINE, Web of Science, and Scopus databases were explored from inception until 19 May, 2022. Only human experimental trials, controlled with a placebo group, evaluating the effects of creatine monohydrate supplementation on endurance performance in a trained population were analyzed in this systematic review and meta-analysis. The methodological quality of included studies was evaluated using the Physiotherapy Evidence Database (PEDro) scale.
Results
A total of 13 studies satisfied all the eligibility criteria and were included in this systematic review and meta-analysis. The results for the pooled meta-analysis showed a non-significant change in endurance performance after creatine monohydrate supplementation in a trained population (p = 0.47), with a trivial negative effect (pooled standardized mean difference = − 0.07 [95% confidence interval − 0.32 to 0.18]; I² = 34.75%). Further, after excluding the studies not evenly distributed around the base of the funnel plot, the results were similar (pooled standardized mean difference = − 0.07 [95% confidence interval − 0.27 to 0.13]; I² = 0%; p = 0.49).
Conclusions
Creatine monohydrate supplementation was shown to be ineffective on endurance performance in a trained population.
Clinical Trial Registration
The study protocol was registered in the Prospective Register of Systematic Review (PROSPERO) with the following registration number: CRD42022327368.
... Creatine (methylguanidine acetic acid) is an amino acid that exists at high concentrations in the skeletal muscle (~95%) and at low concentrations in the testicles (~5%) [1,2]. Approximately two thirds of the intramuscular creatine is phosphocreatine (PCr), and the rest of it is free creatine [3]. ...
Background:
The aims of this study were to analyse the effect of creatine supplementation on the performance improvement in a bench pressing (BP) strength test of muscle failure and to evaluate muscle fatigue and metabolic stress 20 min after the exercise.
Methods:
Fifty young and healthy individuals were randomly assigned to a creatine group (n = 25) or a placebo group (n = 25). Three exercise sessions were carried out, with one week of rest between them. In the first week, a progressive load BP test was performed until the individuals reached the one repetition maximum (1RM) in order to for us obtain the load-to-velocity ratio of each participant. In the second week, the participants conducted a three-set BP exercise protocol against 70% 1RM, where they performed the maximum number of repetitions (MNR) until muscle failure occurred, with two minutes of rest between the sets. After one week, and following a supplementation period of 7 days, where half of the participants consumed 0.3 g·kg-1·day-1 of creatine monohydrate (CR) and the other half consumed 0.3 g·kg-1·day-1 of placebo (PLA, maltodextrin), the protocol from the second week was repeated. After each set, and up to 20 min after finishing the exercise, the blood lactate concentrations and mean propulsive velocity (MPV) at 1 m·s-1 were measured.
Results:
The CR group performed a significantly higher number of repetitions in Set 1 (CR = 14.8 repetitions, PLA = 13.6 repetitions, p = 0.006) and Set 2 (CR = 8 repetitions, PLA = 6.7 repetitions, p = 0.006) after supplementation, whereas no significant differences were seen in Set 3 (CR = 5.3 repetitions, PLA = 4.7 repetitions, p = 0.176). However, there was a significant increase in blood lactate at minute 10 (p = 0.003), minute 15 (p = 0.020), and minute 20 (p = 0.015) after the exercise in the post-supplementation period. Similarly, a significant increase was observed in the MPV at 1 m·s-1 in the CR group with respect to the PLA group at 10, 15, and 20 min after the exercise.
Conclusions:
Although the creatine supplementation improved the performance in the strength test of muscle failure, the metabolic stress and muscle fatigue values were greater during the 20 min of recovery.
... After many years of studies and research, creatine has been given considerable importance in cellular energy metabolism, to the point of being used commercially as a supplement for athletes to improve sports performance and increase muscle mass [16][17][18][19]. ...
Creatine is a very popular amino acid widely utilized in the sports world due to its functions mainly related to muscle building and increasing performance. The present work investigates the behavior of creatine aqueous solutions and of creatine aqueous in the presence of trehalose as a function of time changes by means of Infrared spectroscopy. Infrared spectra have been gathered and studied over time for both the full spectrum and the intramolecular OH-stretching region for the two mixtures. This latter region was studied more specifically using a cutting-edge technique called Spectral Distance (SD). From this analysis of the spectral features of the investigated samples, it emerges that trehalose has a significant stabilizing effect on creatine aqueous solutions.
... It can also be taken into the body through food synthesized from essential and nonessential amino acids (33). Although creatine is mostly found in skeletal muscles (95%) in the body, it is also found in certain amounts (5%) in the brain and testicles (43). Although it has different types structurally, the most widely used and preferred type of creatine is creatine monohydrate (CrM) (37). ...
Creatine, which is a popular ergogenic aid, is shown among the most effective methods used as a performance enhancer in athletes. The aim of this review is to summarize the current publications to show the uses and effects of creatine in exercise. In the present study prepared in a systematic review style, full-text articles about creatine use published in Science Citation Index (SCI), SCI-Expanded, and PubMed/MEDLINE databases' journals between 2010 and 2021 were examined. The searching was performed by "creatine", "creatine monohydrate" and "creatine supplementation" keywords. Data from 46 studies showed that creatine loading in individuals who train during high intensity and short term exercise forms affect performance positively, develop muscle mass/strength and increase muscle creatine phosphate (PCr) stores. It was also found that creatine supplement applied with strength training in elderly individuals increased muscle mass, muscle strength, and movement capacity. It is determined that there is no definitive and clear procedure regarding the usage dosage for creatine. In addition, though some studies have reported that creatine use has a positive effect on cognitive performance, a definite judgment has not been reached. Consequently, it has been demonstrated that creatine supplementation is an effective ergogenic aid for the development of muscle and strength for athletes of all levels. The increase in the number of studies on the creatine usage dosage to be examined in different athlete profiles may lead to a decrease in the contradictions about the usage procedure.
... Creatine is a naturally occurring non-protein nitrogen compound synthesised in the liver and kidney from precursor amino acids, arginine, glycine, and methionine. Most of the body's Cr is found in muscle (95%), of which two-thirds are stored as phosphorylcreatine (PCr), the remaining third as free Cr [3], with less than 5% found in other tissues, such as the brain and testes [4]. In a seminal study by Harris et al. (1992), it was demonstrated for the first time in humans that Cr supplementation, at varying doses of 20-30 g/day, ingested over several individual 5 g doses throughout the day, could increase total intramuscular Cr content (TCr = PCr + Cr) by as much as 20% [5]. ...
Creatine has been considered an effective ergogenic aid for several decades; it can help athletes engaged in a variety of sports and obtain performance gains. Creatine supplementation increases muscle creatine stores; several factors have been identified that may modify the intramuscular increase and subsequent performance benefits, including baseline muscle Cr content, type II muscle fibre content and size, habitual dietary intake of Cr, aging, and exercise. Timing of creatine supplementation in relation to exercise has recently been proposed as an important consideration to optimise muscle loading and performance gains, although current consensus is lacking regarding the ideal ingestion time. Research has shifted towards comparing creatine supplementation strategies pre-, during-, or post-exercise. Emerging evidence suggests greater benefits when creatine is consumed after exercise compared to pre-exercise, although methodological limitations currently preclude solid conclusions. Furthermore, physiological and mechanistic data are lacking, in regard to claims that the timing of creatine supplementation around exercise moderates gains in muscle creatine and exercise performance. This review discusses novel scientific evidence on the timing of creatine intake, the possible mechanisms that may be involved, and whether the timing of creatine supplementation around exercise is truly a real concern.
In 2011, we published a paper providing an overview about the bioavailability, efficacy, and regulatory status of creatine monohydrate (CrM), as well as other “novel forms” of creatine that were being marketed at the time. This paper concluded that no other purported form of creatine had been shown to be a more effective source of creatine than CrM, and that CrM was recognized by international regulatory authorities as safe for use in dietary supplements. Moreover, that most purported “forms” of creatine that were being marketed at the time were either less bioavailable, less effective, more expensive, and/or not sufficiently studied in terms of safety and/or efficacy. We also provided examples of several “forms” of creatine that were being marketed that were not bioavailable sources of creatine or less effective than CrM in comparative effectiveness trials. We had hoped that this paper would encourage supplement manufacturers to use CrM in dietary supplements given the overwhelming efficacy and safety profile. Alternatively, encourage them to conduct research to show their purported “form” of creatine was a bioavailable, effective, and safe source of creatine before making unsubstantiated claims of greater efficacy and/or safety than CrM. Unfortunately, unsupported misrepresentations about the effectiveness and safety of various “forms” of creatine have continued. The purpose of this critical review is to: (1) provide an overview of the physiochemical properties, bioavailability, and safety of CrM; (2) describe the data needed to substantiate claims that a “novel form” of creatine is a bioavailable, effective, and safe source of creatine; (3) examine whether other marketed sources of creatine are more effective sources of creatine than CrM; (4) provide an update about the regulatory status of CrM and other purported sources of creatine sold as dietary supplements; and (5) provide guidance regarding the type of research needed to validate that a purported “new form” of creatine is a bioavailable, effective and safe source of creatine for dietary supplements. Based on this analysis, we categorized forms of creatine that are being sold as dietary supplements as either having strong, some, or no evidence of bioavailability and safety. As will be seen, CrM continues to be the only source of creatine that has substantial evidence to support bioavailability, efficacy, and safety. Additionally, CrM is the source of creatine recommended explicitly by professional societies and organizations and approved for use in global markets as a dietary ingredient or food additive.
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