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Acute fluid volume changes in men during three days of creatine supplementation
... Changes observed in TBW following Cr supplementation in males appear to systematically increase, while data characterizing the distribution of fluid between intra-and extra-cellular compartments are inconsistent [30]. While some short-term loading protocols result in no change in ECF (15,31), similar protocols have resulted in ECF increases of nearly half a liter (∆ 0.42 L) while reporting no change in fluid distribution [18]. Significant increases in ECF (∆ 1.18 L) were reported following a 5-day loading phase in endurance-trained males [21], while a 3-day protocol of 0.07 g Cr/kg FFM every three hours resulted in no significant increase in ECF (p = 0.51) [31]. ...
... While some short-term loading protocols result in no change in ECF (15,31), similar protocols have resulted in ECF increases of nearly half a liter (∆ 0.42 L) while reporting no change in fluid distribution [18]. Significant increases in ECF (∆ 1.18 L) were reported following a 5-day loading phase in endurance-trained males [21], while a 3-day protocol of 0.07 g Cr/kg FFM every three hours resulted in no significant increase in ECF (p = 0.51) [31]. The variation in duration and amount of Cr loading protocols has been hypothesized as a potential cause of ECF outcome discrepancies. ...
... The amount of time elapsed between the end of supplementation and when measurement occurs may be another possible explanation for differences in ECF outcomes. Ziegenfuss et al. (1998) conducted post-supplementation measurements within 24 h following the conclusion of the supplementation protocol and noted an insignificant change, while Weiss and Powers (2006) waited two days to conduct post-supplementation measures. The extended duration of time after supplementation may have impacted the fluid distribution, with increased intra-cellular concentrations resulting from Cr supplementation continuing to draw fluid intra-cellularly over the additional time. ...
This study examined the effects of creatine (Cr) loading on body mass (BM) and fluid markers of total body water (TBW), extra-cellular fluid (ECF), and intra-cellular fluid (ICF) across the menstrual cycle (MC). Thirty moderately active females, either naturally-menstruating (NM) or using hormonal contraceptives (HC), were randomized to Cr (Cr; 4 × 5 g/day of creatine monohydrate for 5 days; n = 15) or a non-caloric placebo (PL; n = 15) using a double-blind, placebo-controlled design, with a menstrual phase crossover. BM, TBW, ECF, and ICF were measured at pre- and post-supplementation in randomized order of follicular phase (FP; NM: MC days 0–8, HC: inactive pill days) or luteal phase (LP; NM: ≤15 days from next projected cycle start date, HC: active pill days) using bioelectrical impedance spectroscopy. Acute hydration status and salivary estrogen were used as covariates. Change in BM was not different between groups across MC ([PL-Cr] Δ 0.40 ± 0.50 kg; p = 0.427) or between MC phase across groups ([FP-LP] Δ 0.31 ± 0.48 kg; p = 0.528). TBW (p = 0.802), ECF (p = 0.373), and ICF (p = 0.795) were not different between supplement groups at pre-supplementation/FP time points. There were no significant differences between the NM and HC subjects at any time point, for any outcome (p > 0.05). Following LP supplementation, significant changes were observed in TBW (Cr: Δ 0.83 ± 0.38 L, PL: Δ −0.62 ± 0.38 L; p = 0.021), ECF (Cr: Δ 0.46 ± 0.15 L, PL: Δ −0.19 ± 0.15 L; p = 0.013), and ICF (Cr: Δ 0.74 ± 0.23 L, PL: Δ −0.02 ± 0.23 L; p = 0.041). These data demonstrate an increase in all fluid compartments in the LP following Cr loading, without observed alterations in body weight for females.
... Chappell et al. reported that~48 % of males and~51 % of females supplemented with creatine during their contest preparation [2]. Creatine has been shown to improve body composition (i.e. increase lean body mass, decrease fat mass) [127,128] and increase intracellular hydration status [129,130]. Ziegenfuss et al. [129] demonstrated that a three day creatine loading phase increased intracellular fluid volume by~3 % without impacting extracellular fluid. The use of multifrequency bioelectrical impedance analysis (MBIA) caused some to initially interpret the data with some skepticism. ...
... Creatine has been shown to improve body composition (i.e. increase lean body mass, decrease fat mass) [127,128] and increase intracellular hydration status [129,130]. Ziegenfuss et al. [129] demonstrated that a three day creatine loading phase increased intracellular fluid volume by~3 % without impacting extracellular fluid. The use of multifrequency bioelectrical impedance analysis (MBIA) caused some to initially interpret the data with some skepticism. ...
... Creatine supplementation has also been shown to aid in glycogen synthesis and supercompensation [132]. Additionally, consuming CHO with creatine increases creatine loading [133], which increases cellular hydration as noted above [32,129]. Finally, muscle creatine levels decline very slowly after loading [134], so creatine intake after peak week glycogen loading is not needed except perhaps in small amounts to potentially accelerate last minute, competition day carbohydrate delivery into skeletal muscle. ...
Bodybuilding is a competitive endeavor where a combination of muscle size, symmetry, “conditioning” (low body fat levels), and stage presentation are judged. Success in bodybuilding requires that competitors achieve their peak physique during the day of competition. To this end, competitors have been reported to employ various peaking interventions during the final days leading to competition. Commonly reported peaking strategies include altering exercise and nutritional regimens, including manipulation of macronutrient, water, and electrolyte intake, as well as consumption of various dietary supplements. The primary goals for these interventions are to maximize muscle glycogen content, minimize subcutaneous water, and reduce the risk abdominal bloating to bring about a more aesthetically pleasing physique. Unfortunately, there is a dearth of evidence to support the commonly reported practices employed by bodybuilders during peak week. Hence, the purpose of this article is to critically review the current literature as to the scientific support for pre-contest peaking protocols most commonly employed by bodybuilders and provide evidence-based recommendations as safe and effective strategies on the topic.
... -1 dry mass, increasing osmolarity and, subsequently, the total quantity of intramuscular liquid. Water accumulation may therefore be an important factor contributing to the increase in lean muscle mass (Ziegenfuss et al., 1998;Zorzano et al., 2000). ...
... Previous studies have reported increases in total body mass after oral creatine supplementation (Becque et al., 2000;Kamber et al., 1999;Mihic et al., 2000). Because this compound is osmotically active (hygroscopic), higher creatine concentration can induce an increase in the cell water volume, which would explain the rapid increase in volume of the muscular tissue observed after creatine supplementation (Juhn, 1999;Ziegenfuss et al., 1998). However, few studies have attempted to test this hypothesis. ...
... A signifi cant increase in lean mass for a period shorter than 12 days cannot have been brought about by an increase in protein content; therefore, the increase in MCM seen in our study may have been a result of absorption of water by the tissues. This hypothesis was supported in studies conducted by Ziegenfuss et al. (1998). Berneis et al. (1999) showed that a prolonged increase in intracellular osmolarity may signal an increase in the synthesis or point to a lessening of protein degradation. ...
... Creatine supplementation also increases LM (14). Following Cr uptake, extracellular water (ECW) is absorbed by muscle via osmosis in order to restore intramuscular protein levels (16)(17)(18), and the resulting increase in mechanical stress caused by the expansion in intracellular water (ICW) has been proposed to act as an anabolic signal for protein synthesis (18)(19)(20). ...
... The changes in ALM following 12 weeks Cr supplementation were reflected in changes in body water, specifically a significant 1.08 L increase in TBW due to expansion of both ICW (0.64 L), and ECW (0.44 L) during this period. Similar changes in body water were observed in younger adults following Cr supplementation (17,18,20). The mechanisms by which Cr supplementation increases TBW and shifts fluid into the intracellular space are unclear (17). ...
... Similar changes in body water were observed in younger adults following Cr supplementation (17,18,20). The mechanisms by which Cr supplementation increases TBW and shifts fluid into the intracellular space are unclear (17). However, it is has been suggested that as skeletal ...
Objective. Rheumatoid cachexia (muscle wasting) in rheumatoid arthritis (RA) patients contributes to substantial reductions in strength and impaired physical function. The objective of this randomised control trial was to investigate the effectiveness of oral creatine (Cr) supplementation in increasing lean mass and improving strength and physical function in RA patients.
Method. In a double-blind design, 40 RA patients, were randomised to either 12 weeks supplementation of Cr or placebo. Body composition (dual energy x-ray absorptiometry, DXA, and bioelectrical impedance spectroscopy, BIS), strength and objectively-assessed physical function were measured at: baseline, day 6, week 12 and week 24. Data analysis was performed by ANCOVA.
Results. Creatine supplementation increased appendicular lean mass (ALM; a surrogate measure of muscle mass) by 0.52 (± 0.13) kg (P = 0.004 versus placebo), and total LM by 0.60 (± 0.37) kg (P = 0.158). The change in LM concurred with the gain in intracellular water (0.64 ± 0.22 L, P = 0.035) measured by BIS. Despite increasing ALM, Cr supplementation, relative to placebo, failed to improve isometric knee extensor (P = 0.408), handgrip strength (P = 0.833), or objectively-assessed physical function (P's = 0.335 – 0.764).
Conclusion. In patients with RA, creatine supplementation increased muscle mass, but not strength or objective physical function. No treatment-related adverse effects were reported suggesting that Cr supplementation may offer a safe and acceptable adjunct treatment for attenuating muscle loss; this treatment may be beneficial for patients suffering from severe rheumatoid cachexia.
... An early investigation (1) demonstrated marked weight gains (3.2 and 3.8 kg) in two subjects administered creatine for 29 and 34 days, respectively. More recent studies have typically demonstrated gains of one kg or greater (2)(3)(4)(5)(6)(7)(8)(9)(10), and researchers arbitrarily suggest water retention as a possible causative factor (4), yet few researchers have addressed this issue directly (11). ...
... Hultman et al. (12) reported a mean decrement of 600 ml in urinary output among 31 male subjects following 6 days of creatine ingestion, which was markedly lower than the response to placebo ingestion. Additionally, recent work of Ziegenfuss et al. (11) indicated both body mass gains and expansion of total body water with 3 days of creatine supplementation. Using multifrequency bioimpendance analysis (MBIA), the investigators noted that the increase in body water was isolated to the intracellular volume (ICV) and not evident in the extracellular volume (ECV) compartment of the muscle. ...
... Hultman et al. (12) detected a decrement (0.6 L) in urinary volume during the first few days of creatine ingestion and explained the increase in body mass as attributable to water retention. Furthermore, data utilizing MBIA suggested an increase in the intracellular volume of the muscle and corresponding elevations in total body water and intracellular water following 3 days of supplementation (11). The increase in volume was attributed to water retention caused by the osmotic load resulting from an increase in the storage of creatine within the cell. ...
Physiological Response To Exercise In The Heat Following Creatine Supplementation. JEPonline. 2001;4(2):18-27. The current investigation evaluated body water changes and indicators of heat tolerance with 28 days of creatine (CR) or placebo (PLC) supplementation. Twenty college-aged males were assigned to receive creatine or placebo in a randomized double blind fashion. Body weight, body water, hematocrit, and body composition were measured before and after the treatment period. Additionally, heart rate and core temperature responses to 60 minutes of exercise in the heat (37°C, 25% RH) were assessed. The CR group had greater gains in total body water (p=0.050) and body weight (p=0.034) than the PLC group. The rise in core temperature during the cycle ride was attenuated by creatine supplementation in comparison to placebo consumption. Gains in total body water over the four weeks were related to the attenuation of temperature rise during the ride following supplementation (n=19; r=0.569, p=0.011). No significant differences were detected for percent body fat, hematocrit values, or heart rate response to exercise. These results suggest that body weight gains with CR supplementation may partially reflect body water changes and may help attenuate the thermal burden associated with exercise in the heat.
... In general, short-term supplementation regimes of ~20-25 g of creatine for 5-7 days have yielded a 0.7-1.6 kg body mass increase (3,27,64,70,71). Most scientists believe that increases in body mass in response to shortterm creatine supplementation are a result of the retention of water (4,38,72,73) and the elevation of creatine stores (65). Hultman et al. (38) have reported that there is a marked reduction in urinary volume during the initial days of creatine supplementation. ...
... Hultman et al. (38) have reported that there is a marked reduction in urinary volume during the initial days of creatine supplementation. Ziegenfuss et al. (72,73) have also reported a 2% increase in total body water and a 3% increase in intracellular fluid volume (measured with multifrequency bioimpedance) in response to a shortterm creatine supplementation regime in aerobic and crosstrained males. Balsom et al. (4) also suggest that water retention is a primary cause of the increase in body mass associated with short-term creatine supplementation (6 days). ...
... Body mass increased in the Cr group, and this was anticipated as it is in accordance with previous studies [21,25]. Following Cr ingestion, the muscle uptake of Cr increases muscle osmolality, leading to acute water entry into the muscle in order to maintain homeostasis, hence the observed rise in body mass due to increases in intracellular and total body water [64,65] without any changes in extracellular body water [64]. A correlation between body weight gain and power output was revealed by the statistical analysis and may indicate that those who increase their body mass during such short-term supplementation protocols [23] exhibit a concomitant increase their performance. ...
... Body mass increased in the Cr group, and this was anticipated as it is in accordance with previous studies [21,25]. Following Cr ingestion, the muscle uptake of Cr increases muscle osmolality, leading to acute water entry into the muscle in order to maintain homeostasis, hence the observed rise in body mass due to increases in intracellular and total body water [64,65] without any changes in extracellular body water [64]. A correlation between body weight gain and power output was revealed by the statistical analysis and may indicate that those who increase their body mass during such short-term supplementation protocols [23] exhibit a concomitant increase their performance. ...
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.
... It does appear that the most common adverse effect of creatine supplementation is water retention in the early stages (first several days) [36]. For example, studies have shown that three days of creatine supplementation increased TBW and extracellular body water (ECW) [37] and intracellular water (ICW) [38]. Unfortunately, based on these short-term responses, this notion that creatine increases water retention over the longterm has been widely accepted [39]. ...
... In the early 2000's, with limited data and based primarily on speculation, the American College of Sports Medicine (ACSM) recommended that individuals controlling their weight and exercising intensely or in hot environments should avoid the use of creatine supplementation [74]. The physiological rationale suggesting that creatine supplementation may cause dehydration and muscle cramping is based on the premise that creatine is an osmotically active substance found primarily in skeletal muscle and may alter whole-body fluid distribution by preferentially increasing intracellular water uptake and retention, particularly over the short-term [38,75]. In situations of body water loss, such as severe sweating from exercise and/or increased environmental temperature, the bound intracellular fluid, in theory, may be detrimental to thermal regulation and lead to extracellular dehydration, electrolyte imbalance and muscle cramping or other heat-related musculoskeletal issues [44]. ...
Supplementing with creatine is very popular amongst athletes and exercising individuals for improving muscle mass, performance and recovery. Accumulating evidence also suggests that creatine supplementation produces a variety of beneficial effects in older and patient populations. Furthermore, evidence-based research shows that creatine supplementation is relatively well tolerated, especially at recommended dosages (i.e. 3-5 g/day or 0.1 g/kg of body mass/day). Although there are over 500 peer-refereed publications involving creatine supplementation, it is somewhat surprising that questions regarding the efficacy and safety of creatine still remain. These include, but are not limited to: 1. Does creatine lead to water retention? 2. Is creatine an anabolic steroid? 3. Does creatine cause kidney damage/renal dysfunction? 4. Does creatine cause hair loss / baldness? 5. Does creatine lead to dehydration and muscle cramping? 6. Is creatine harmful for children and adolescents? 7. Does creatine increase fat mass? 8. Is a creatine ‘loading-phase’ required? 9. Is creatine beneficial for older adults? 10. Is creatine only useful for resistance / power type activities? 11. Is creatine only effective for males? 12. Are other forms of creatine similar or superior to monohydrate and is creatine stable in solutions/beverages? To answer these questions, an internationally renowned team of research experts was formed to perform an evidence-based scientific evaluation of the literature regarding creatine supplementation.
... Generally, skeletal muscle significantly increases its Cr content over the first 2-3 days of supplementation. During this time, the osmotic effects of Cr uptake are assumed to be responsible for body water retention, leading to a reduction in urine output typically being observed (Ziegenfuss et al., 1998). Cr has frequently been taken together with carbohydrates and this combination seems to increase its uptake into the skeletal muscle, probably due to the effect of insulin. ...
... The Cr supplementation effectiveness on endurance capacity can be attributed to several mechanisms: (1) PCr aids ATP resynthesis, in a decreasing role in relation to duration and intensity of muscle work (Bangsbo et al., 1990); (2) Cr may help produce ATP aerobically, considering the ESS function of Cr between the mitochondria and muscle fibers (Wallimann et al., 1992); and (3) muscle Cr can support anaerobic glycolysis and this may lead to a reduced intramuscular lactate production (Earnest and Rasmussen, 2015). Furthermore, based on the osmotic effects of Cr uptake (Ziegenfuss et al., 1998) ...
... There are individuals who supplement creatine and associate the acute sensation of cellular swelling as indicator of effectiveness. Although it has been described to occur acutely [105], the current evidence supporting cellular swelling induced by creatine ingestion as a direct mechanism for muscle hypertrophy are lacking. However, there is a rationale that supports such a physiological phenomenon. ...
... That is, creatine supplementation can promote body fluid retention but that does not result in lower extracellular fluid volume and, consequently, does not affect body temperature regulation or increase the incidence of muscle cramps. We conclude that although increases in intracellular water content and increases in body weight have been described after 3 d of creatine supplementation [105], prolonged increases in body water does not seem to be compartmentalized in favor of intraD 3 9 X X versus extracellular spaces. Thus, it is still unknown to what degree, if, at all, cellular swelling mechanisms are responsible for creatine's anabolic effects. ...
Increased blood flow via vasodilation, metabolite production, and venous pooling contribute to the hyperaemia and cellular swelling experienced during resistance training. These effects have been suggested to play a role in hypertrophic adaptations. Over the past two decades sport supplement products have been marketed to promote exercise hyperaemia and intracellular fluid storage, and thereby enhance hypertrophy via acute swelling of myocytes. The three main classes of supplements hypothesized to promote exercise-induced hyperaemia include: vasodilators, such as nitric oxide precursor supplements; anaerobic energy system ergogenic aids that increase metabolite production, such as beta-alanine and creatine; and organic osmolytes, such as creatine and betaine. Previous studies indicated that these dietary supplements are able to improve muscle performance and thus enhance muscle hypertrophy; however, recent evidences also point to these three classes of supplements affecting “secondary” physiological determinants of muscle mass accretion such as vasodilation, metabolite accumulation and muscle cellular swelling. Although we recognize that the literature is relatively scarce regarding these topics, a better comprehension and discussion of these determinants can lead to increased knowledge and guide further research regarding the proposed mechanisms of action of the identified compounds. In this case, increased knowledge may contribute to the development of improved efficacy, new products, or direct new research to specifically investigate those secondary effects. From this discussion, new perspectives associated with “secondary physiological effects” induced by supplementation will be brought into focus and its relevance will be determined.
... Total body water has been reported to increase up to 3 litres (+9%) [45] ; of which intra-cellular water has been shown to increase by between 0.77-3.0 litre (an increase of +3%-9% from baseline values) (e.g., [53][54][55][56] ) in the absence of changes in extra-cellular water [54] . ...
... Total body water has been reported to increase up to 3 litres (+9%) [45] ; of which intra-cellular water has been shown to increase by between 0.77-3.0 litre (an increase of +3%-9% from baseline values) (e.g., [53][54][55][56] ) in the absence of changes in extra-cellular water [54] . ...
Creatine is a popular and widely used form of protein supplementation due to its efficacy in improving performance in healthy athletic populations via increased muscle mass and enhanced adenosine triphosphate (ATP) energy regeneration. If these effects of creatine supplementation were to be replicated in patients with rheumatoid arthritis (RA), then considerable clinical and patient benefit would ensue, as RA is a condition characterised by generalised muscle loss and substantially impaired physical function. The muscle loss inherent in RA is termed ‘rheumatoid cachexia,’ and its adverse consequences include reduced strength and physical function and, consequently, diminished quality of life. Whilst regular high-intensity exercise training has been shown to increase muscle mass and restore function in RA patients, this form of therapy has very low uptake amongst RA patients. Thus, acceptable alternatives are required. The aim of this review is to consider the potential efficacy of creatine as an anabolic and ergonomic therapy for RA patients. To date, only two studies have supplemented RA patients with creatine, and the findings from these investigations are inconsistent and inconclusive. However, trials in populations with similar losses of muscle mass and function as RA, including older adults and those with other muscle wasting conditions, indicate that creatine could be an efficacious way of improving muscle mass, strength and physical function in RA patients, and may offer an easy, safe and cheap means of treating rheumatoid cachexia and its consequences.
... The addition of CHO to a traditional Cr loading strategy (20 gId j1 for 3-5 d) has previously been reported to increase muscle glycogen stores (18,34). The basis for this response has centered around the idea that greater intracellular water retention is associated with increased Cr transport, which subsequently increases cell volume, promoting a greater capacity for glycogen storage (12,22,25,34,37). Nelson and colleagues (18) showed that subjects who consumed a moderate CHO (~6.6 gIkg j1 BM) diet after traditional Cr loading increased muscle glycogen content by 53% above those consuming high CHO alone. ...
... Cr induced a significant increase in BM compared with PLA, indicating that our ingestion protocol promoted additional intracellular water storage. Cell swelling caused by Cr and CHO loading via the storage of additional water within the muscle cells has been associated with the up-regulation of a large number of signaling markers involved in protein and glycogen synthesis (12,22,25,37). It has been hypothesized that Cr-mediated cell swelling may further result in the increased expression of key proteins involved in hypertrophyrelated signal transduction (7), namely, mTOR (14). ...
Introduction:
Creatine (Cr) and carbohydrate loadings are dietary strategies used to enhance exercise capacity. This study examined the metabolic and performance effects of a combined CR and CHO loading regiment on time trial (TT) cycling bouts.
Methods:
Eighteen well-trained (~65 mL·kg·min V˙O2peak) men completed three performance trials (PT) that comprised a 120-km cycling TT interspersed with alternating 1- and 4-km sprints (six sprints each) performed every 10 km followed by an inclined ride to fatigue (~90% V˙O2peak). Subjects were pair matched into either CR-loaded (20 g·d for 5 d + 3 g·d for 9 d) or placebo (PLA) groups (n = 9) after the completion of PT1. All subjects undertook a crossover application of the carbohydrate interventions, consuming either moderate (6 g·kg body mass (BM) per day; MOD) or CHO-loaded (12 g·kg BM·d; LOAD) diets before PT2 and PT3. Muscle biopsies were taken before PT1, 18 h after PT1, and before both PT2 and PT3.
Results:
No significant differences in overall TT or inclined ride times were observed between intervention groups. PLA + LOAD improved power above baseline (P < 0.05) during the final 1-km sprint, whereas CR + MOD and CR + LOAD improved power (P < 0.05) during the final 4-km sprint. Greater power was achieved with MOD and LOAD compared with baseline with PLA (P < 0.05). CR increased pre-PT BM compared with PLA (+1.54% vs +0.99% from baseline). CR + LOAD facilitated greater [total CR] (P < 0.05 vs baseline) and muscle [glycogen] (P < 0.01 vs baseline and MOD) compared with PLA + LOAD. Mechanistic target of rapamycin decreased from baseline after glycogen depletion (~30%; P < 0.05).
Conclusions:
Power output in the closing sprints of exhaustive TT cycling increased with CR ingestion despite a CR-mediated increase in weight. CR cosupplemented with carbohydrates may therefore be beneficial strategy for late-stage breakaway moments in endurance events.
... The changes in TBW, ICW, and ECW when supplementing with creatine have been well documented [19,27,28]. These fluid volume shifts have also been suggested to be responsible for the observed weight gain associated with creatine supplementation, particularly in the early stages of supplementation prior to alterations in skeletal muscle [7,29]. ...
... No differences between day 3 and day 7 may be a result of adaptation of the body to the supplementation protocol. Previous research has shown that over a 3 d period there are increases in TBW, ICW, and ECW when compared to baseline [27], in addition, other investigators have reported increases in TBW, ICW, and ECW Schedel et al. [10] reported that consumption of creatine (20g single dose) resulted in increased SCR within the first hour of ingestion and reached maximum levels at about 2.5 hours following ingestion [10]. Additionally, Harris et al. [4] reported increases in plasma creatine within approximately 1 hr of consumption. ...
... Creatine is known to increase intracellular fluid volume [41], which may increase glycogen [42] and protein [43] synthesis, and has been proposed as a mechanism of performance enhancement [41,44]. However, investigation of creatine's influence on protein synthesis has led to conflicting results in both animals [45,46] and humans [47][48][49][50]. ...
... Creatine is known to increase intracellular fluid volume [41], which may increase glycogen [42] and protein [43] synthesis, and has been proposed as a mechanism of performance enhancement [41,44]. However, investigation of creatine's influence on protein synthesis has led to conflicting results in both animals [45,46] and humans [47][48][49][50]. ...
The training regimens of modern-day athletes have evolved from the sole emphasis on a single fitness component (e.g., endurance athlete or resistance/strength athlete) to an integrative, multimode approach encompassing all four of the major fitness components: resistance (R), interval sprints (I), stretching (S), and endurance (E) training. Athletes rarely, if ever, focus their training on only one mode of exercise but instead routinely engage in a multimode training program. In addition, timed-daily protein (P) intake has become a hallmark for all athletes. Recent studies, including from our laboratory, have validated the effectiveness of this multimode paradigm (RISE) and protein-feeding regimen, which we have collectively termed PRISE. Unfortunately, sports nutrition recommendations and guidelines have lagged behind the PRISE integrative nutrition and training model and therefore limit an athletes’ ability to succeed. Thus, it is the purpose of this review to provide a clearly defined roadmap linking specific performance enhancing diets (PEDs) with each PRISE component to facilitate optimal nourishment and ultimately optimal athletic performance.
... Total body water has been reported to increase up to 3 litres (+9%) [45] ; of which intra-cellular water has been shown to increase by between 0.77-3.0 litre (an increase of +3%-9% from baseline values) (e.g., [53][54][55][56] ) in the absence of changes in extra-cellular water [54] . ...
... Total body water has been reported to increase up to 3 litres (+9%) [45] ; of which intra-cellular water has been shown to increase by between 0.77-3.0 litre (an increase of +3%-9% from baseline values) (e.g., [53][54][55][56] ) in the absence of changes in extra-cellular water [54] . ...
Creatine is one of the most popular forms of protein supplements and is known to improve performance in healthy athletic populations via enhanced muscle mass and adenosine triphosphate energy regeneration. Clinical use of creatine may similarly benefit patients with rheumatoid arthritis (RA), an inflammatory condi-tion characterised by generalised muscle loss termed "rheumatoid cachexia". The adverse consequences of rheumatoid cachexia include reduced strength, physi-cal function and, as a consequence, quality of life. Whilst regular high-intensity exercise training has been shown to increase muscle mass and restore function in RA patients, this form of therapy has very low uptake amongst RA patients. Thus, acceptable alternatives are required. The aim of this review is to consider the potential efficacy of creatine as an anabolic and ergo-nomic therapy for RA patients. To date, only one study has supplemented RA patients with creatine, and the findings from this investigation were inconclusive. How-ever, trials in populations with similar losses of muscle mass and function as RA, including older adults and those with other muscle wasting conditions, indicate that creatine is an efficacious way of improving muscle mass, strength and physical function, and may offer an easy, safe and cheap means of treating rheumatoid ca-chexia and its consequences.
Core tip: Creatine supplementation primarily improves physical function by enhancing the re-synthesis of ade-nosine triphosphate via increased stores of phosphocre-atine in the muscle. Through this pathway it provides greater levels of energy during physical activity and improves recovery. Creatine also augments muscle pro-tein synthesis, thereby increasing muscle mass. These dual effects increase strength, reduce fatigue, and thereby improve function. In patients with conditions such as rheumatoid arthritis that are characterised by muscle loss and subsequent reductions in strength and physical function, creatine offers a potential therapeutic intervention for augmenting muscle mass and function that is safe, easy and inexpensive to administer. Wilkinson TJ, O'Brien TD, Lemmey AB. Oral creatine supple-mentation: A potential adjunct therapy for rheumatoid arthritis patients. World J Rheumatol 2014; 4(3): 22-34 Available from:
... The increases in muscle hypertrophy are due to increases in intracellular water retention, which lead to the increase in cross sectional area seen within skeletal muscle (Bemben & Lament, 2005). During 3 days of supplementation 90% of the increase in body mass was shown to be due to increases in total body water without a significant effect on extra cellular volume (Ziegenfuss, 1998). Roughly two-thirds of the total body water is intracellular. ...
... A potential benefit of creatine supplementation is through the action of an anabolic signal for skeletal muscle hypertrophy, with increases in total and intracellular water (Mesa, 2002;Persky & Brazeau, 2001). Roughly two-thirds of the increases in total body water seen during supplementation are intracellular, with no fluid shift occurring (Powers et al., 2003;Ziegenfuss, 1998). Mean increases in total body water ( Figure 8) from T1 to T4 were 2.43L, 2.64L, and 1.95L for PLA, CR, and CEE groups, respectively. ...
Thesis Chairperson: Darryn S. Willoughby, Ph.D. Creatine monohydrate has become one of the most popular ingested nutritional supplements due to its potential enhancement of athletic performance. Creatine absorption from the serum into skeletal muscle occurs through the utilization of a membrane-spanning protein, CreaT1. Numerous creatine formulations have been developed primarily to maximize creatine absorption. Creatine ethyl ester (CEE) has been chemically modified by adding an ester group and is thought to increase creatine bio-availability by by-passing the CreaT1. This study examined how a seven week supplementation regimen with CEE affected body composition, muscle mass and performance, whole body creatine retention, as well physiological and molecular adaptations, associated with creatine uptake in nonresistance-trained males following a resistance-training program. Results demonstrated that CEE did not show any additional benefit to increases in muscle strength/performance or a significant increase in total muscle creatine when compared to creatine monohydrate or placebo. CEE supplementation did show a large increase in creatinine levels throughout the study.
... Another theory suggests that since creatine has been suggested to promote fluid retention, it may alter electrolyte status and thereby promote muscle cramping by interfering with the muscle's contraction/relaxation mechanisms (2,4,40). Over the last few years, a number of studies have examined the effects of creatine supplementation on hydration status, electrolyte levels, and dehydration during exercise performed in the heat (20)(21)(22)(23)(41)(42)(43). Results of these studies have indicated that creatine does not promote dehydration, alter electrolyte levels, or increase thermal stress. ...
... In addition, there has been no evidence that creatine supplementation promotes muscle cramping among athletes (21,23,37,(44)(45)(46)(47)(48)(49)(50). In fact, recent studies have indicated that creatine supplementation may actually promote hydration (21,23,41), reduce thermal stress during exercise in the heat (23,42), and/or possible reduce the incidence of injury based on occurrence rates (11,17,31,33,37,(44)(45)(46)(47)(49)(50)(51)(52). The results of our study suggest that the incidence of cramping and dehydration observed among creatine users was lower or proportional to non-users. ...
... Increases in total and lean body mass are commonly reported following short-term creatine supplementation [139]. As creatine is osmotically active, increased concentrations within skeletal muscle elevate intracellular water volume, with short-term fluid retention attributed to acute increases in body mass [140]. Increases in intracellular osmotic pressure promote water movement into the cell, thereby increasing cellular volume [141]. ...
Global warming is attributed to an increased frequency of high ambient temperatures and humidity, elevating the prevalence of high-temperature-related illness and death. Evidence over recent decades highlights that tailored nutritional strategies are essential to improve performance and optimise health during acute and chronic exertional-heat exposure. Therefore, the purpose of this review is to discuss the efficacy of various nutritional strategies and ergogenic aids on responses during and following acute and chronic exertional-heat exposure. An outline is provided surrounding the application of various nutritional practices (e.g., carbohydrate loading, fluid replacement strategies) and ergogenic aids (e.g., caffeine, creatine, nitrate, tyrosine) to improve physiological, cognitive, and recovery responses to acute exertional-heat exposure. Additionally, this review will evaluate if the magnitude and time course of chronic heat adaptations can be modified with tailored supplementation practices. This review highlights that there is robust evidence for the use of certain ergogenic aids and nutritional strategies to improve performance and health outcomes during exertional-heat exposure. However, equivocal findings across studies appear dependent on factors such as exercise testing modality, duration, and intensity; outcome measures in relation to the ergogenic aid’s proposed mechanism of action; and sex-specific responses. Collectively, this review provides evidence-based recommendations and highlights areas for future research that have the potential to assist with prescribing specific nutritional strategies and ergogenic aids in populations frequently exercising in the heat. Future research is required to establish dose-, sex-, and exercise-modality-specific responses to various nutritional practices and ergogenic aid use for acute and chronic exertional-heat exposure.
... A Cross-sectional Pilot Study in Thi-Qar Provence, Southern Iraq acid administration was significantly higher in male aspects than in females (P<0.000). However, excessive consumption of branched-chain amino acids (BCAAs) is associated with an increased risk of type 2 diabetes [21][22][23]. ...
... The addition of GAA to NAP diets did not affect BY. In humans, an increase in intramuscular phosphocreatine can increase cell volume [25]. This increase in volume is thought to be caused by the osmotic draw of water into the cell, which can increase both protein and glycogen synthesis and decrease accumulation of lactic acid [26,27]. ...
Creatine is a central constituent in energy metabolism, especially in cells with variable energy demand, such as muscle cells. Animal proteins such as fish meal, poultry meal, and meat meal may provide adequate amounts of creatine when included in diet formulation. Guanidinoacetic acid (GAA) is an immediate precursor of creatine and should be considered for use in animal nutrition. An experiment was conducted to describe broiler performance and carcass yield effects when GAA was provided to broilers consuming diets containing either animal protein or nonanimal protein. Treatments were arranged in a 2 × 2 factorial varying in basal ingredients (conventional [CON] or nonanimal protein [NAP]) and GAA inclusion (0 or 0.06%), provided as CreAmino, in a randomized complete block design. Treatments were applied to 12 replicate pens of 36 Hubbard × Cobb 500 straight-run broilers from hatch through d 42. Overall (d1-42) results indicate 0.019 FCR improvement when GAA was included to broiler diets (P = 0.0024). Similar results were apparent in each feed phase period (P < 0.05). Processing yield results indicate a 45-g increase in breast weight when GAA was included in broiler diets (P = 0.0354). Basal ingredients and GAA inclusion effects interacted, which affected d42 breast yield (BY) (P = 0.0443). The inclusion of GAA in NAP diets did not affect BY; however, BY was reduced by 1.78 percentage points when broilers were provided the CON diet devoid of GAA. GAA has the potential to improve broiler performance and BY when included in broiler diets with basal ingredients including conventional animal protein.
... 97 This increase in body mass is most likely due to the Cr induced changes in total body water (TBW). The majority of literature 28, 56,57,86,97,112,114 attributes the increase in TBW to increases in intracellular water (ICW) credited to Cr pulling water into the cell. Another possible explanation attributes the weight gain to an increase in dry matter growth. ...
The purposes of the present study were to determine the effect of Creatine (Cr) supplementation on 1) voluntary isometric and isokinetic strength and 2) active and passive range of motion (ROM) during loading and the subsequent washout period. The secondary purpose was to address any possible underlying neuromuscular mechanisms that might influence these changes. Using a double-blinded, placebo-controlled, matched-paired, randomized design, 40 males were assigned to a Cr (n=20, age: 20.3 ± 2.1 yrs,) or a placebo group (Pl; 20.4 ± 2.3 yrs) group. Participants supplemented four times daily for five days with 5g Cr + 20g dextrose or 20g dextrose. Testing was conducted prior to supplementation, during the loading phase (days 2, 4 & 6), and during the washout period (day 20 & 35). Muscular strength was examined with a maximal isometric and isokinetic (30, 90 & 120°*sec-1) muscle action of the plantar flexors on a calibrated isokinetic dynamometer. Muscle activation was determined by examining percent voluntary activation (%VA) and normalized electromyographic (EMG) amplitudes. Passive ROM , common and relative passive stiffness values were determined from a slow passive ROM assessment on a dynamometer. Active ROM was determined as the maximal dorsiflexion possible. Total body water, extracellular water, and intracellular water were measured with Bioimpedance Spectroscopy. Panoramic ultrasound imaging was used to address architectural changes in muscle cross sectional area, pennation angle, and fascicle length. Resting evoked twitch properties were performed to examine Cr-induced changes in Ca²+ kinetics. Magnetic resonance spectroscopy (MRS) was used to evaluate Cr uptake by the muscle in a subset of participants (Cr = 4; Pl = 4). Mass and fluid distribution for the Cr group did not significantly (P>0.11) differ from the Pl group over the course of the study. There was no significant interactions for all strength measures (P>0.36) or active and passive ROM (P>0.15), or any of the possible underlying mechanism (P>0.05). There were no changes in Cr stores (P>0.05). Overall, the results of this study suggest that Cr supplementation alone does not influence neuromuscular function or any of the underlying factors that could improve strength or limit ROM.
... suplementa??o aguda de creatina ? devido a reten??o de ?gua, principalmente no compartimento intracelular (ZIEGENFUSS et al., 1998) Ingest?o de creatina no treinamento de for?a A ingest?o de creatina, por praticantes de muscula??o, corrobora para o melhor desempenho f?sico, ganho de for?a muscular e hipertrofia muscular, devido aumento nas reservas intramusculares de fosfocreatina e, consequentemente, eleva??o o ritmo de ress?ntese de ATP (LEITE et al., 2015). ...
... A limitation of the current study was that muscle mass and body water were not measured. Nevertheless, the acute increase in body mass is most likely due to an increase in total body water (Ziegenfuss et al. 1998) and not an increase in muscle protein or muscle mass (Gotshalk et al., 2008). ...
THE EFFECTS OF CREATINE SUPPLEMENTATION ON SPRINT
RUNNING PERFORMANCE AND SELECTED HORMONAL RESPONSES
Hassan FARAJI*, Hamid ARAZI**, Dariush SHEIKHOLESLAMI VATANI ***
& Mehdi HAKIMI**
* Department of Physical Education & Sport Science, Islamic Azad University Marivan
Branch, Marivan, Iran
**Faculty of Physical Education and Sport Science, University of Guilan, Rasht, Iran
***Department of Physical Education & Sport Science, University of Kurdistan,
Sanandaj, Iran
ABSTRACT
The purpose of this study was to determine the influence of short-term creatine
supplementation on sprint running performance (100 and 200 m) and circulating
hormone [growth hormone (GH), testosterone and cortisol] concentrations. Twenty
amateur male runners were randomly divided into a creatine supplementation
group, or placebo group. Subjects were provided with capsules containing either
creatine monohydrate or identical powdered cellulose placebo. Daily creatine
monohydrate supplementation was 20 g/day parceled into three equal dosages to be
consumed with each major meal. Subjects were tested for performance and resting
blood hormone concentrations before and after six days. A double-blind research
design was employed in this study. After this creatine loading, the mean running
performance time of the creatine supplementation group decreased significantly in
the 100 m, but not the 200 m. Serum GH, testosterone, and cortisol concentrations
were not affected by creatine supplementation. It can therefore be concluded that
although short-term creatine supplementation was found to improve sprint
performance in the 100 m in amateur runners, this performance improvement did not
appear to be hormonally mediated.
Key words: Sprint performance; Creatine supplementation; Hormonal
responses; Creatine loading.
... It was also assumed that since the creatine is stored intramuscularly, the increased water retention would also be primarily reflected in an increase in the intracellular water compartment. While this seemed to be true, especially based on some bioelectrical impedance studies, measurement with deuterium and sodium bromide dilution techniques have not established a differential shift in the increased water compartments (Ziegenfuss et al. 1998;Powers et al. 2003). ...
... Creatine supplementation has shortand long-term side effects. The side effects of short-term use for 3 to 5 days include an increase in body weight due to increase in total body water [16], and the longterm use of creatine (2 months) may result in limb edema in some trainers [17]. Despite these minimal side effects, the supplements mentioned above are legal to use by the International Olympic Committee (IOC) and the National Collegiate Athletic Association (NCAA) [18,19]. ...
Background. Several studies showed that regular gymnasium users use various dietary supplements without comprehension of their potential risks. Objective. To determine the prevalence and dietary supplement intake and assess the awareness of supplement use among regular gymnasium users in Riyadh, Saudi Arabia. Methods. A descriptive cross-sectional study was conducted among regular gymnasium users in Riyadh, Saudi Arabia, between April 2015 and June 2015. A validated structured questionnaire was used. Results. The study included 299 participants. Of these 113 (37.8%) were dietary supplements users and this was more common among males than females (44.7% versus 16.4%). Gender based analysis showed that males were exercising more frequently than females and the type of cardiovascular exercise was more among them. The most commonly used supplements were whey protein (22.1%), amino acids (16.8%), multivitamins (16.8%), creatine (11.5%), and omega 3 (11.5%). The reasons for taking dietary supplements were to improve body shape (47.7%), increase health (44.2%), and improve performance (41.5%). Conclusion. Most of the information about supplements was obtained from unreliable sources. More studies are needed to better understand supplements use and their impact on health in Saudi Arabia.
... Although muscle PCr was not measured directly, the increase in body mass shown by the creatine group was consistent with that reported in previous research (10). Moreover, the lack of any corresponding increase in body fat conforms to reports that most of the increase in body mass after short-term creatine supplementation is because of an increase in fluid retention (25,50). Although it is possible that the increase in body mass may have counteracted any ergogenic effect of creatine supplementation, this seems unlikely given the relatively small increase in body mass concerned and the fact that investigations into the influence of creatine supplementation on multiple sprint running (1,2,15,34,42,43) display the same contradictions as those using nonweight-bearing protocols (5,14,27,28,30,33,51). ...
... En general, la mayoría de las investigaciones centradas en la evaluación de los efectos de la suplementación con Cr han reportado un incremento en el contenido de volumen del fluido intracelular sin cambios notorios en el volumen del espacio externo de la célula (Ziegenfuss et al. 1998 ). Se ha postulado que la razón del incremento de agua intracelular es la elevada carga osmótica asociada con el incremento en la concentración de Cr al interior de la célula tras el periodo de suplementación (Bemben & Lamont 2005). ...
... En general, la mayoría de las investigaciones centradas en la evaluación de los efectos de la suplementación con Cr han reportado un incremento en el contenido de volumen del fluido intracelular sin cambios notorios en el volumen del espacio externo de la célula (Ziegenfuss et al. 1998 ). Se ha postulado que la razón del incremento de agua intracelular es la elevada carga osmótica asociada con el incremento en la concentración de Cr al interior de la célula tras el periodo de suplementación (Bemben & Lamont 2005). ...
Desde hace más de 30 años, la suplementación con creatina (Cr) y la descripción de sus efectos sobre el rendimiento deportivo a corto y largo plazo se han convertido en el principal objeto de estudio de muchos investigadores. No obstante, en los últimos años el problema de investigación en el campo del uso de suplementos ergogénicos ha cambiado al punto de pretender explicar los mecanismos metabólicos por los cuales la administración de Cr incrementa algunas capacidades metabólicas que favorecen la ejecución de ciertos deportes o simplemente benefician la adaptación muscular. El propósito de esta revisión es analizar los principales fundamentos metabólicos que explican los efectos de la ingesta de Cr durante el ejercicio, enfatizando en entrenamiento de resistencia. Los mecanismos principales que sustentan estos efectos involucran principalmente la mayor biodisponibilidad energética de Cr optimizando la acción buffer espacial/temporal que ofrece el sistema Cr/PCr/CK, que conlleva a un mayor rendimiento de ATPasas miocelulares, incremento en la resíntesis de PCr, reducción en la acumulación de Pi, Ca2+, H+ y ADP, mayor disponibilidad de aminoácidos, inhibición de glucólisis y un posible aumento del rendimiento neuromuscular. Asimismo, un incremento en los procesos de proliferación y diferenciación de células musculares evaluados por la activación de cascadas de señalización y el aumento en la expresión de proteínas implicadas en estos procesos (IGF-I/PI3K/Akt, SPHK1/MAPK/p38/MEF-2/MRFs, posiblemente mTOR, MHC, CK, Ca2+-ATPasa del retículo sarcoplasmático, polimerización de actina y fusión de mioblastos) y la inactivación y/o reducción en la expresión de proteínas con funciones ergolíticas (GSK3β, miostatina y posiblemente AMPK) explican bioquímicamente los efectos que tiene el monohidrato de Cr sobre el rendimiento deportivo. Así, el monohidrato de Cr parece ser el suplemento nutricional más efectivo y seguro para aumentar la masa muscular, la fuerza, la resistencia a la fatiga y el rendimiento en ejercicios de alta intensidad, entre muchos otros efectos positivos sobre la salud.
Palabras clave: Sistema Cr/PCr/CK, Monohidrato de Creatina, Suplemento Ergogénico, Metabolismo Energético Miocelular, Ejercicio de Resistencia, Cascada de Señalización
Bonilla DA. PubliCE 2013
... The current study also supports an increase in ECW. Other studies have observed increased ICW following CrM supplementation with concomitant declines in ECW [14,20] . With CrM being osmotically active, it can have dehydrating effects when consumed with minimal fluids. ...
Creatine monohydrate (CrM) is considered a safe nutritional supplement. The loading phase of CrM supplementation is associated with shifts in total body water and plasma volume that may affect blood pressure. However, few studies have measured blood pressure during the loading phase of CrM supplementation. Purpose: The aim of this study was to determine if CrM supplementation in nor-motensive college-aged males induces a daily blood pressure increase during the supplementation-loading phase. Methods: Participants' blood pressure, shoulder extension active range of motion (AROM), arm girth, arm volume, plasma volume, blood volume, hematocrit, and hemoglobin were measured daily for five days of supplementation (4x5gxd-1 x5d) of either CrM (n=12) or placebo (P; n=12). Results: The CrM group did not experience significant changes in systolic blood pressure (mmHg) (CrM 126.67±1.94 Day5 ; P 125.50±2.61 Day5) or diastolic blood pressure (mmHg) (CrM 83.83±2.19 Day5 ; P 82.33±2.07 Day5) compared to P. A significant T x Tx interaction (p=0.001) and Tx effect (p=0.03) support decreased AROM (cm) in the CrM group compared to P (CrM 38.3±2.19 Day 1 , CrM 34.0±2.01 Day5 ; P 41.02±2.49 Day 1 , P 43.2±2.47 Day5). An increase in arm volume (ml) in the CrM group (CrM 2443±99.44 Day 1 , CrM 2470±92.21 Day5) vs. the P group (P 2372±74.44 Day 1 , P 2374±74.61 Day5 ; p=0.026) was observed. An increase in plasma volume (%Δ from baseline) (p=0.014) (CrM 1.48±2.60 Day2 , CrM 6.03±4.03 Day5 ; P 3.25±2.74 Day2 , P 5.05±2.91 Day5) and a decrease in hematocrit (%) (p=0.026) (CrM 0.47±0.01 Day 1 , 0.45±0.01 Day5 ; P 0.46±0.01 Day 1 , 0.45±0.01 Day5) were observed. Conclusion: Findings suggest CrM supplementation in the loading phase does not affect blood pressure in normotensive college-aged males. CrM reduces shoulder extension AROM presumably due to increased tissue volume secondary to fluid shifts.
... HULTMAN et al. (1996) demonstraram que a suplemen-tação de Cr reduziu o volume urinário em aproximadamente 0,6 L durante os dias iniciais de suplementação, sugerindo que o aumento da massa corporal se deve principalmente à retenção hídrica. ZIEGENFUSS et al. (1998) confirmaram essa teoria, acrescentando que o acúmulo de líquido seria principalmente observado no meio intracelular. Durante o período de carga, os indivíduos costumam apresentar ganho de 0,5 a 1 kg de peso. ...
O objetivo desta revisao e expor os potenciais dos suplementos ergogenicos nutricionais dentro da musculacao, destacando os aspectos historicos, regulamentacao, tipos, efeitos ergogenicos, efeitos adversos, principais fontes, suplementacao, aspectos legais e eticos, e os possiveis mecanismos de acao e sua relacao com o desempenho fisico. A busca foi realizada em livros, artigos de revistas cientificas, artigos extraidos via Internet, buscados nos bancos de dados da MEDLINE, LILACS, SCIENCE DIRECT, PERIODICOS CAPES, PUBMED e SCIELO. As discussoes da presente revisao poderao servir como base de estudo e planejamento das acoes estrategicas de treinadores e fisiologias do exercicio no que refere ao uso de suplementacao ergogenica nutricional na melhoria da performance dentro da musculacao. ABSTRACT The purpose of this review is to demonstrate the potential ergogenic nutritional supplements in the bodybuilding, highlighting the historical aspects, regulations, types, ergogenic effects, adverse effects, major sources, supplements, legal and ethical aspects, and possible mechanisms of action and its relation with physical performance. The search was conducted in books, scientific journal articles, articles taken from the Internet, searched in the databases of MEDLINE, LILACS, SCIENCE DIRECT JOURNALS CAPES, PubMed and Scielo. The discussions of these in this review may serve as a basis for study and planning of strategic actions of coaches and exercise physiologists as regards the use of ergogenic nutritional supplementation in improving performance in the gym.
... Um dos primeiros estudos que analisou as mudanças relativas no volume de fluido corporal durante a suplementação de Cr foi realizado por Ziegenfuss, et al. 23 . Nesta pesquisa, 10 homens treinados consumiram 0,07 g de creatina por quilo de massa livre de gordura durante 3 dias. ...
... A limitation of the current study was that muscle mass and body water were not measured. Nevertheless, the acute increase in body mass is most likely due to an increase in total body water (Ziegenfuss et al. 1998) and not an increase in muscle protein or muscle mass (Gotshalk et al., 2008). ...
The purpose of this study was to determine the influence of short-term creatine supplementation on sprint running performance (100 and 200 m) and circulating hormone [growth hormone (GH), testosterone and cortisol] concentrations. Twenty amateur male runners were randomly divided into a creatine supplementation group, or placebo group. Subjects were provided with capsules containing either creatine monohydrate or identical powdered cellulose placebo. Daily creatine monohydrate supplementation was 20 g/day parceled into three equal dosages to be consumed with each major meal. Subjects were tested for performance and resting blood hormone concentrations before and after six days. A double-blind research design was employed in this study. After this creatine loading, the mean running performance time of the creatine supplementation group decreased significantly in the 100 m, but not the 200 m. Serum GH, testosterone, and cortisol concentrations were not affected by creatine supplementation. It can therefore be concluded that although short-term creatine supplementation was found to improve sprint performance in the 100 m in amateur runners, this performance improvement did not appear to be hormonally mediated.
... The important question is, what accounts for the increase in muscle volume: water, protein, or a combination of both? Prior investigation used multifrequency bioimpedance analysis to assess changes in body fluid compartments after CrS, and suggested that approximately 90% of the weight gain associated with the initial days of CrS can be accounted for by increases in total body water, and that much of this increase is contained within the intracellular compartment, at least when Cr is congested with a high glycemic index beverage [34,35]. ...
The purpose of this study was to compare the effects of 3, 5, and 7 days of creatine loading coupled with resistance training on skeletal muscle volume and functional performance. Twenty active males were randomly assigned in a double-blind fashion to either the creatine group (Cr) (n=10) or the placebo group (Pl) (n=10). The Cr group consumed 20g of creatine per day (4 doses of 5g per day for 7 days), whereas the Pl group was given dextrose. The subjects performed resistance training at days 3, 5, and 7; and were tested also at days 4, 6, and 8. Significant increases in strength and standing long jump were observed after 3, 5, and 7 days of Cr ingestion (p < 0.05). There were significant improvements at 5 days in contrast to 3 days in body weight, 45-m sprint, standing long jump, 1RM back squat and arm curl (p < 0.05). Seven days of Cr loading made significantly greater improvements than 3 and 5 days in 4 × 9-m shuttle run and the arm cross-sectional area (p < 0.05). We conclude that more than 5 days of creatine regime are sufficient for improving muscle cross-sectional area, body weight, power and agility, whereas 3 days are sufficient for enhancing muscular strength.
... Previous studies that have examined creatine's influence on TBW and fluid distribution are varied with some studies reporting (a) no change in TBW, 87 (b) increases in all fluid compartments, 88 (c) increases in TBW with no change in intracellular fluid, 86 and (d) increases in TBW that are due primarily to increases in intracellular fluid. 87,[89][90][91] Despite these discrepancies, it has been speculated that the potential alteration in fluid distribution may compromise thermoregulation. 18 In theory, creatine is an osmotically active substance stored primarily in skeletal muscle that will lead to an increase in intracellular osmotic pressure resulting in greater intracellular fluid volume. ...
In 1992, Harris and colleagues demonstrated that oral creatine supplementation can enhance muscle creatine stores. Since then, creatine has become an important and popular ergogenic aid for improving athletic performance with reports of up to 74% of athletes supplementing with creatine. Although many recent studies have addressed the safety concerns of creatine supplementation on hydration status in hot and humid environments, anecdotal reports still exist linking creatine usage to heat-related problems. These concerns are based on the premise that creatine is an osmotically active substance resulting in an alteration in fluid balance by increasing intracellular fluid volume and preventing fluid from entering the extracellular environment to aid in thermoregulation. However, a number studies have demonstrated that when recommended amounts of creatine are consumed, creatine does not appear to increase the risk of heat-related problems during exercise and may actually have a positive influence on core temperature and heart rate responses.
... Although muscle PCr was not measured directly, the increase in body mass shown by the creatine group was consistent with that reported in previous research (10). Moreover, the lack of any corresponding increase in body fat conforms to reports that most of the increase in body mass after short-term creatine supplementation is because of an increase in fluid retention (25,50). Although it is possible that the increase in body mass may have counteracted any ergogenic effect of creatine supplementation, this seems unlikely given the relatively small increase in body mass concerned and the fact that investigations into the influence of creatine supplementation on multiple sprint running (1,2,15,34,42,43) display the same contradictions as those using nonweight-bearing protocols (5,14,27,28,30,33,51). ...
... Recovery: fasting data collected the following morning after exercise treatment supplemental strategy (12 g creatine/day for 15 days) was effective. The increase in body mass after creatine consumption was explained by increasing in fat-free-mass [32,33] and water retention in muscle [34,35]. The inadequacy in washout period, leading to the water (accumulated from the endurance trial with creatine supplementation) retained in the athletes of power trial without creatine supplementation, resulted in an increase in the body weight before sprint running. ...
Purpose:
Few studies have focused on the metabolic changes induced by creatine supplementation. This study investigated the effects of creatine supplementation on plasma and urinary metabolite changes of athletes after endurance and sprint running.
Methods:
Twelve male athletes (20.3 ± 1.4 y) performed two identical (65-70 % maximum heart rate reserved) 60 min running exercises (endurance trial) before and after creatine supplementation (12 g creatine monohydrate/day for 15 days), followed by a 5-day washout period. Subsequently, they performed two identical 100 m sprint running exercises (power trial) before and after 15 days of creatine supplementation in accordance with the supplementary protocol of the endurance trial. Body composition measurements were performed during the entire study. Plasma samples were examined for the concentrations of glucose, lactate, branched-chain amino acids (BCAAs), free-tryptophan (f-TRP), glutamine, alanine, hypoxanthine, and uric acid. Urinary samples were examined for the concentrations of hydroxyproline, 3-methylhistidine, urea nitrogen, and creatinine.
Results:
Creatine supplementation significantly increased body weights of the athletes of endurance trial. Plasma lactate concentration and ratio of f-TRP/BCAAs after recovery from endurance running were significantly decreased with creatine supplementation. Plasma purine metabolites (the sum of hypoxanthine and uric acid), glutamine, urinary 3-methylhistidine, and urea nitrogen concentrations tended to decrease before running in trials with creatine supplements. After running, urinary hydroxyproline concentration significantly increased in the power trial with creatine supplements.
Conclusions:
The findings suggest that creatine supplementation tended to decrease muscle glycogen and protein degradation, especially after endurance exercise. However, creatine supplementation might induce collagen proteolysis in athletes after sprint running.
... Although muscle PCr was not measured directly, the increase in body mass shown by the creatine group was consistent with that reported in previous research (10). Moreover, the lack of any corresponding increase in body fat conforms to reports that most of the increase in body mass after short-term creatine supplementation is because of an increase in fluid retention (25,50). Although it is possible that the increase in body mass may have counteracted any ergogenic effect of creatine supplementation, this seems unlikely given the relatively small increase in body mass concerned and the fact that investigations into the influence of creatine supplementation on multiple sprint running (1,2,15,34,42,43) display the same contradictions as those using nonweight-bearing protocols (5,14,27,28,30,33,51). ...
The aim of this study was to examine the effects of short-term creatine monohydrate supplementation on multiple sprint running performance. Using a double-blind research design, 42 physically active men completed a series of 3 indoor multiple sprint running trials (15 3 30 m repeated at 35-second intervals). After the first 2 trials (familiarization and baseline), subjects were matched for fatigue score before being randomly assigned to 5 days of either creatine (4[middle dot]d-1 x 5 g creatine monohydrate 1 1g maltodextrin) or placebo (4[middle dot]d-1 x 6 g maltodextrin) supplementation. Sprint times were recorded via twin-beam photocells, and earlobe blood samples were drawn to evaluate posttest lactate concentrations. Relative to placebo, creatine supplementation resulted in a 0.7 kg increase in body mass (95% likely range: 0.02 to 1.3 kg) and a 0.4% reduction in body fat (95% likely range: 20.2 to 0.9%). There were no significant (p > 0.05) between-group differences in multiple sprint measures of fastest time, mean time, fatigue, or posttest blood lactate concentration. Despite widespread use as an ergogenic aid in sport, the results of this study suggest that creatine monohydrate supplementation conveys no benefit to multiple sprint running performance.
(C) 2006 National Strength and Conditioning Association
... Based on this notion, it has been reasoned that vegetarians, a population with low initial muscle creatine content and limited dietary intake, may respond better to creatine supplementation (Burke et al., 2003). What is noteworthy is that creatine supplementation has been associated with increased fluid retention, which may contribute to increased osmotic load in the muscle (Ziegenfuss et al., 1998). Another study by Ziegenfuss et al. (2002) has documented about a 6.5% increase in thigh muscle volume, as measured by magnetic resonance imaging, after six maximal 10-s cycle sprints coupled with 3 days of creatine supplementation. ...
IntroductionGeneral nutritional guidelines for sprint and power-trained athletesPower-type exercises and muscle protein synthesisSprint-type exercises and muscle protein synthesisCreatine supplementationGeneral conclusionsReferences
... These results are similar to previous fi ndings (Gotshalk, et al., 2008). Since there were no signifi cant alterations in restingValues are mean ± SD obtained from skinfold analyses *p<.05 from Pre value for the CR group circulating anabolic hormones, it is suggested that the acute increase in body mass is most likely due to an increase in total body water (Ziegenfuss, Lowery, & Lemon, 1998) and not an increase in muscle protein. Cellular hydration is an important mechanism in metabolic control and hypohydration appears to have a detrimental effect on performance (Judelson, et al., 2007). ...
The purpose of this study was to determine the influence of short-term creatine supplementation on hormonal responses to resistance exercise. 27 trained men were randomly divided into a creatine supplementation group [the CR group (n=15), taking 4×5 g creatine monohydrate/day] or a placebo supplementation group [the PL group (n=12), taking 4×7.5 g maltodextrin/day]. A double-blind research design was employed for a 7-day supplementation period. After this period, the participants performed exercise testing. Blood tests occurred on day 1 prior to supplementation loading (1Pre) and after this period [on the exercise testing day: pre-exercise (Pre), immediately post-exercise (IP), and 15 (15P) and 30 (30P) minutes post-exercise] for the measurement of the serum growth hormone and testosterone concentrations. Significant differences in the number of repetitions and volume were seen with CR (7.2±1.3 repetitions, 1560±386 kg) compared to PL (5.6±2 repetitions, 1089±341 kg) at set 5 of the exercise protocol (p=.01). Serum growth hormone and testosterone were significantly higher at 15P in CR (6.1±1.8 ng/ml, 70.1±19 pmol/L) compared to PL (4.1±1.7 ng/ml, 44.8±16 pmol/L) [(p=.02), (p=.01)]. The enhanced exercise performance resulted in a significantly greater increase in both the growth hormone and testosterone concentrations, indicating an augmented anabolic hormone response to creatine supplementation.
Background:
Acute fluid ingestion increases estimated body fat percentage (BF%) measurements by single frequency (SF-BIA) and multi-frequency bioelectrical impedance (MF-BIA). It is unknown if MF-BIA accurately measures total BF% and total body water (TBW) after creatine supplementation, which causes fluid retention, and resultant increases in fat-free mass and TBW. The purpose of this study was to analyze the effect of creatine supplementation on body composition and TBW measured through a popular MF-BIA device (InBody 770).
Methods:
Thirteen male and 14 female subjects (18-22 years) completed one week of creatine monohydrate (0.3 g/kg body weight) or maltodextrin. Pre- and post-supplementation body composition measurements included dual-energy X-ray absorptiometry (DEXA), SF-BIA measured by an Omron HBF-306C device, and MF-BIA measured by an InBody 770 device to measure BF%, fat free mass (FFM), and fat mass (FM). Additionally, intracellular water (ICW), extracellular water (ECW), and TBW were estimated by MF- BIA.
Results:
FFM increased more in the creatine group than the placebo group measured by all body composition modes (1.2 kg, 1.9 kg, and 1.1 kg increase for SF-BIA, MF-BIA, and DEXA respectively, P<0.05). Creatine supplementation resulted in a 2% increase (P<0.05) in TBW measured by MF-BIA (40.4±9.5 to 41.2±9.6 kg).
Conclusions:
One week of creatine supplementation increased TBW as detected by the InBody 770 device. Changes in body composition that occurred due to the increase in TBW were detected as an increase in FFM measured by SF-BIA, MF-BIA, and DEXA.
Employing nutritional ergogenic aids is an established practice for supporting exercise training-induced performance gains in almost every athletic sphere. Concurrent training (i.e. combining resistance with endurance exercise) poses unique physiological challenges that likely require specific tailoring of nutritional strategies. In particular, nutrition for the concurrent athlete aims to: (1) support muscle growth for maximising hypertrophic response that occurs when resistance training is performed in conjunction with endurance exercise whilst (2) promoting aerobic adaptation in the face of strength training. This chapter discusses the potential role of macronutrients, and a list of emerging ‘nutraceuticals’, to provide the backdrop for maximising physiological adaptations to concurrent training.
Nanostructure materials or nanomaterials research takes a materials science-based approach to nanotechnology, leveraging advances in dope or un-doped materials metrology and facile synthesis which have been developed in support of various chemical and nano or micro fabrication research. Nanomaterials (NMs) have unique properties, such as optical, structural, electronic, chemical, or mechanical in every dimensions with nanoscale range. In this chapter, a low-dimensional antimony-doped tin oxide aggregated nanoparticles (ATO NPs) were synthesized using hydrothermal method in alkaline phase. The optical, morphological, and structural properties of ATO NPs were characterized in details using FTIR, UV-Vis, FESEM, XEDS, XPS, TEM and XRD techniques. Flat glassy carbon electrode (GCE) was fabricated with a thin-layer of aggregated ATO NPs by conducting coating binders (5% Nafion) for the development of selective and sensitive enzyme-less creatine (Crt) sensor. Electrochemical responses along with higher sensitivity, large-dynamic range and long-term stability towards Crt were performed by electrochemical I-V approach. The calibration curve was found linear over a wide linear dynamic range of Crt concentration. It is an organized route for the development of non-enzymatic Crt biosensor based on ATO NPs embedded GCE using electrochemical reduction phenomena and significantly applied for the real analysis. As far as we know, this report is the maiden publication on highly sensitive Crt biosensor based on the ATO NPs/GCE. This method could be a pioneer development in Crt sensitive biosensor development using ATO NPs in reliable I-V method for the important biosensor applications with useful doped materials coupled nano-technological system.
Anecdotal reports suggest that creatine supplementation during intense training and competition may increase the incidence of muscle cramping and injury. This study examined the effects of creatine supplementation on cramping and injury during collegiate baseball training and competition. Thirty-nine Division I baseball players participated in this study. Twenty-one (54.0%) of the thirty-nine athletes ingested 15 to 25g/d of creatine for 5 days followed by 5 g/day of creatine that was mixed with sports drinks or water. Athletes who were non-creatine users had access to a carbohydrate drink that contained no creatine (placebo) during the training/competition period. Injuries treated by the athletic training staff were recorded and categorized as cramping, heat/dehydration, muscle tightness, muscle strains, non-contact injuries joint injuries, contact injuries, and illness. The number of practices missed due to injury and illness were also recorded. While no heat/dehydration events were reported by either group, results revealed that creatine-users had significantly fewer total injuries, ?2 (1)=4.69, p=0.03 than non-creatine users (p<0.05). However, there were no significant differences between groups regarding cramping, ?2 (1)=2.94, p=0.08, muscle tightness, ? 2 (1)=3.01, p=0.08, muscle strains, ?2 (1)=2.92, p=0.08, non-contact joint injuries, ?2 (1)=1.04, p=0.31, contact injuries, ?2 (1)=0.009, p=.92, illness, ?2 (1)=0.02, p=0.95, missed practices due to injury, ?2 (1)=.103, p=0.74, and players lost for the season, ?2 (1)=2.45, p=0.11. Based on the findings in this investigation, creatine supplementation during collegiate baseball training and competition does not appear to increase the incidence of injury or cramping. Additional research is warranted to evaluate the effect of creatine supplementation on athletes training in hot/humid climates.
Creatine is physiologically provided equally by diet and by endogenous synthesis from arginine and glycine with successive involvements of arginine glycine amidinotransferase [AGAT] and guanidinoacetate methyl transferase [GAMT]. A specific plasma membrane transporter, creatine transporter [CRTR] (SLC6A8), further enables cells to incorporate creatine and through uptake of its precursor, guanidinoacetate, also directly contributes to creatine biosynthesis. Breakthrough in the role of creatine has arisen from studies on creatine deficiency disorders. Primary creatine disorders are inherited as autosomal recessive (mutations affecting GATM [for glycine-amidinotransferase, mitochondrial]) and GAMT genes) or X-linked (SLC6A8 gene) traits. They have highlighted the role of creatine in brain functions altered in patients (global developmental delay, intellectual disability, behavioral disorders). Creatine modulates GABAergic and glutamatergic cerebral pathways, presynaptic CRTR (SLC6A8) ensuring re-uptake of synaptic creatine. Secondary creatine disorders, addressing other genes, have stressed the extraordinary imbrication of creatine metabolism with many other cellular pathways. This high dependence on multiple pathways supports creatine as a cellular sensor, to cell methylation and energy status. Creatine biosynthesis consumes 40% of methyl groups produced as S-adenosylmethionine, and creatine uptake is controlled by AMP activated protein kinase, a ubiquitous sensor of energy depletion. Today, creatine is considered as a potential sensor of cell methylation and energy status, a neurotransmitter influencing key (GABAergic and glutamatergic) CNS neurotransmission, therapeutic agent with anaplerotic properties (towards creatine kinases [creatine-creatine phosphate cycle] and creatine neurotransmission), energetic and antioxidant compound (benefits in degenerative diseases through protection against energy depletion and oxidant species) with osmolyte behaviour (retention of water by muscle). This review encompasses all these aspects by providing an illustrated metabolic account for brain and body creatine in health and disease, an algorithm to diagnose metabolic and gene bases of primary and secondary creatine deficiencies, and a metabolic exploration by (1)H-MRS asssessment of cerebral creatine levels and response to therapeutic measures.
OBJETIVO: Verificar as alterações promovidas pela suplementação de creatina nas variáveis antropométricas e da resultante de força máxima dinâmica (RFMD) em universitários submetidos a oito semanas de treinamento de força. METODOLOGIA: Participaram deste estudo, 18 universitários do sexo masculino, com idade entre 19 e 25 anos. Antes do treinamento foram determinadas a estatura (cm), a massa corporal (kg) e testes de ação muscular voluntária máxima dinâmica (1AMVMD), os sujeitos foram assinalados a um dos dois grupos, A (creatina) e B (placebo), foi adotado o protocolo duplo-cego. Após oito semanas de treinamento de força, repetiu-se a bateria de testes do pré-treinamento. RESULTADOS: Após oito semanas, verificou-se que tanto no grupo A como no B houve alterações estatisticamente significantes (ES) na RFMD em todos os exercícios (p = 0,007 a 0,008). A análise da melhora percentual e do delta da RFMD, nos exercícios de agachamento, desenvolvimento e supino fechado, mostrou que o grupo A teve alterações positivas ES superiores ao grupo B (p = 0,008 a 0,038). A massa magra aumentou ES somente no grupo A (p = 0,038). Contudo, o percentual de gordura corporal não mostrou alterações em nenhum dos grupos. A relação entre a melhora percentual (MP) das circunferências (C) do braço e antebraço e a MP na RFMD do exercício de desenvolvimento foi ES (r = 0,481 e 0,546, respectivamente), bem como entre a MP na C da coxa e na MP da RFMD do exercício de agachamento (r = 0,619). CONCLUSÃO: Independente do suplemento ingerido o treinamento de força foi capaz de induzir ajustes positivos na RFMD; contudo, a suplementação de creatina mostrou-se mais eficiente que o placebo, induzindo a maior aumento percentual e de delta na força.
Objectives – This literature review will attempt to shed light on controversies raised by creatine (Cr) supplementation, particularly at the level of intramuscular total creatine content (TCr), physical performance and body composition.Topics – Many studies have demonstrated significant increases of 16–20% in TCr stores, after a daily dose of 20–30 g of Cr ingestion over two–six days. Concerning the ergogenic effect of Cr on anaerobic performance in sedentary and active subjects, results are very ambiguous. As for the anabolic role of various Cr regimens, an increase in body mass (1.5 kg only, on average) is often reported while unobserved in many other studies. Due to the small number of studies and the variety in methods used for body composition changes, it is difficult to identify the components that are affected by these changes. In fact, some have observed significant gains in lean body mass in subjects ingesting Cr, while others have not. Body weight gain might be due to an increase in intracellular or total body water, but this hypothesis has recently been challenged.Future prospects – The magnitude of inter-individual variations alone could explain the substantial differences found in these studies. Change in muscle mass needs to be measured with more specific methods.
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