Creatine supplements how does it work

Learn More. Creatine is one of the most popular and widely researched natural supplements. Regardless of the form, supplementation with creatine has regularly shown to increase strength, fat free mass, and muscle morphology with concurrent heavy resistance training more than resistance training alone.

Creatine may be of benefit in other modes of exercise such as high-intensity sprints or endurance training. However, it appears that the effects of creatine diminish as the length of time spent exercising increases.

Even though not all individuals respond similarly to creatine supplementation, it is generally accepted that its supplementation increases creatine storage and promotes a faster regeneration of adenosine triphosphate between high intensity exercises. These improved outcomes will increase performance and promote greater training adaptations.

More recent research suggests that creatine supplementation in amounts of 0. Finally, although presently ingesting creatine as an oral supplement is considered safe and ethical, the perception of safety cannot be guaranteed, especially when administered for long period of time to different populations athletes, sedentary, patient, active, young or elderly.

Synthesis predominately occurs in the liver, kidneys, and to a lesser extent in the pancreas. As creatine is predominately present in the diet from meats, vegetarians have lower resting creatine concentrations [ 2 ]. Creatine is used and researched in a clinical setting to investigate various pathologies or disorders such as myopathies [ 3 , 4 ] and is also used as an ergogenic aid for improving health and sports performance in athletes [ 5 ].

As an oral supplement, the most widely used and researched form is creatine monohydrate CM. When orally ingested, CM has shown to improve exercise performance and increase fat free mass [ 5 - 9 ].

There is a great amount of research published on creatine supplementation; protocols of administration, forms of creatine, as well as potential side effects. Despite this, the mechanisms by which creatine acts in the human body to improve physical and cognitive performance are still not clear.

The main objectives of this review are to analyze the more recent findings on the effects and mechanisms of creatine supplementation in sports and health. As a secondary purpose, we will analyze the most recommended protocols of ingestion and its potential side effects. The average 70 kg young male has a creatine pool of around g which varies between individuals [ 10 , 11 ] depending on the skeletal muscle fiber type [ 1 ] and quantity of muscle mass [ 11 ].

The endogenous production and dietary intake matches the rate of creatinine production from the degradation of phosphocreatine and creatine at 2.

In general, oral creatine supplementation leads to an increase of creatine levels within the body. Creatine can be cleared from the blood by saturation into various organs and cells or by renal filtration [ 1 ]. Three amino acids glycine, arginine and methionine and three enzymes L-arginine:glycine amidinotransferase, guanidinoacetate methyltransferase and methionine adenosyltransferase are required for creatine synthesis.

The impact creatine synthesis has on glycine metabolism in adults is low, however the demand is more appreciable on the metabolism of arginine and methionine [ 11 ]. Creatine ingested through supplementation is transported into the cells exclusively by CreaT1.

However, there is another creatine transporter Crea T2, which is primarily active and present in the testes [ 12 ]. Creatine uptake is regulated by various mechanisms, namely phosphorylation and glycosylation as well as extracellular and intracellular levels of creatine.

Crea T1 has shown to be highly sensitive to the extracellular and intracellular levels being specifically activated when total creatine content inside the cell decreases [ 12 ]. It has also been observed that in addition to cytosolic creatine, the existence of a mitochondrial isoform of Crea T1 allows creatine to be transported into the mitochondria.

Indicating another intra-mitochondrial pool of creatine, which seems to play an essential role in the phosphate-transport system from the mitochondria to the cytosol [ 13 ].

Myopathy patients have demonstrated reduced levels of total creatine and phosphocreatine as well as lower levels of CreaT1 protein, which is thought to be a major contributor to these decreased levels [ 14 ].

There is a positive relationship between muscle creatine uptake and exercise performance [ 17 ]. Volek et al [ 18 ] observed a significant increase in strength performance after 12 weeks creatine supplementation with a concurrent periodized heavy resistance training protocol.

These positive effects were attributed to an increased total creatine pool resulting in more rapid adenosine triphosphate ATP regeneration between resistance training sets allowing athletes to maintain a higher training intensity and improve the quality of the workouts along the entire training period.

It is regularly reported that creatine supplementation, when combined with heavy resistance training leads to enhanced physical performance, fat free mass, and muscle morphology [ 18 - 22 ]. However, contradicting studies have reported no effects of creatine supplementation on strength performance. Jakobi et al [ 23 ] found no effects of a short term creatine loading protocol upon isometric elbow flexion force, muscle activation, and recovery process.

However, this study did not clearly state if creatine supplementation was administered concurrent with resistance training. Bemben et al [ 24 ] have shown no additional benefits of creatine alone or combined with whey protein for improving strength and muscle mass after a progressive 14 weeks 3 days per week resistance training program in older men. These conflicting results can be explained by the possibility that the supplemented groups were formed by a greater amount of non-responders or even because creatine supplementation was administered on the training days only 3 times a week.

This strategy has not been adequately tested as effective in middle aged and older men for maintaining post loading elevated creatine stores [ 5 ].

A quantitative, comprehensive scientific summary and view of knowledge up to on the effects of creatine supplementation in athletes and active people was published in a citation review position paper by the International Society of Sports Nutrition [ 5 ].

Saremi et al [ 26 ] reported a change in myogenic transcription factors when creatine supplementation and resistance training are combined in young healthy males.

It was found that serum levels of myostatin, a muscle growth inhibitor, were decreased in the creatine group. Collectively, in spite of a few controversial results, it seems that creatine supplementation combined with resistance training would amplify performance enhancement on maximum and endurance strength as well muscle hypertrophy.

Creatine has demonstrated neuromuscular performance enhancing properties on short duration, predominantly anaerobic, intermittent exercises. A previous meta-analysis [ 28 ] reported an overall creatine supplementation effect size ES of 0. For this short high-intensity exercise, creatine supplementation resulted in a 7. When looking at the individual selected measures for anaerobic performance the greatest effect of creatine supplementation was observed on the number of repetitions which showed an ES of 0.

Furthermore, an increase from base line of The second greatest ES was on the weight lifted at 0. This would indicate that creatine supplementation might be useful to attenuate fatigue symptoms over multiple bouts of high-intensity, short duration exercise. The specific aspects of anaerobic endurance performance improved by creatine supplementation were work and power, both of which had a mean ES greater than 0.

Cribb et al [ 29 ] observed greater improvements on 1RM, lean body mass, fiber cross sectional area and contractile protein in trained young males when resistance training was combined with a multi-nutrient supplement containing 0.

These findings were novel because at the time no other research had noted such improvements in body composition at the cellular and sub cellular level in resistance trained participants supplementing with creatine. The authors speculated that creatine in addition to a single bout of resistance training can favor an anabolic environment by inducing changes in gene expression after only 5 days of supplementation.

When creatine supplementation is combined with heavy resistance training, muscle insulin like growth factor IGF-1 concentration has been shown to increase.

Burke et al [ 2 ] examined the effects of an 8 week heavy resistance training protocol combined with a 7 day creatine loading protocol 0. Additionally, vegetarians within the supplemented group had the largest increase of lean mass compared to non vegetarian 2.

Changes in lean mass were positively correlated to the modifications in intramuscular total creatine stores which were also correlated with the modified levels of intramuscular IGF The authors suggested that the rise in muscle IGF-1 content in the creatine group could be due to the higher metabolic demand created by a more intensely performed training session.

These amplifying effects could be caused by the increased total creatine store in working muscles. Even though vegetarians had a greater increase in high energy phosphate content, the IGF-1 levels were similar to the amount observed in the non vegetarian groups.

These findings do not support the observed correlation pattern by which a low essential amino acid content of a typical vegetarian diet should reduce IGF-1 production [ 33 ]. According to authors opinions it is possible that the addition of creatine and subsequent increase in total creatine and phosphocreatine storage might have directly or indirectly stimulated production of muscle IGF-I and muscle protein synthesis, leading to an increased muscle hypertrophy [ 2 ].

Although creatine supplementation has been shown to be more effective on predominantly anaerobic intermittent exercise, there is some evidence of its positive effects on endurance activities. Branch [ 28 ] highlights that endurance activities lasting more than s rely on oxidative phosphorylation as primary energy system supplier. From this meta analysis [ 28 ], it would appear that the ergogenic potential for creatine supplementation on predominantly aerobic endurance exercise diminishes as the duration of the activity increases over s.

However it is suggested that creatine supplementation may cause a change in substrate utilization during aerobic activity possibly leading to an increase in steady state endurance performance. However, the effects of creatine supplementation on endurance performance have been questioned by some studies. Graef et al [ 35 ] examined the effects of four weeks of creatine citrate supplementation and high-intensity interval training on cardio respiratory fitness.

A greater increase of the ventilatory threshold was observed in the creatine group respect to placebo; however, oxygen consumption showed no significant differences between the groups. The total work presented no interaction and no main effect for time for any of the groups. In addition, of the concern related to the dosage used in these studies, it could be possible that the potential benefits of creatine supplementation on endurance performance were more related to effects of anaerobic threshold localization.

It is suggested [ 16 , 37 ] that another mechanism for the effect of creatine could be enhanced muscle glycogen accumulation and GLUT4 expression, when creatine supplementation is combined with a glycogen depleting exercise. Whereas it has been observed [ 38 ] that creatine supplementation alone does not enhance muscle glycogen storage. Hickner et al [ 15 ] observed positive effects of creatine supplementation for enhancing initial and maintaining a higher level of muscle glycogen during 2 hours of cycling.

In general, it is accepted that glycogen depleting exercises, such as high intensity or long duration exercise should combine high carbohydrate diets with creatine supplementation to achieve heightened muscle glycogen stores [ 39 ]. Creatine supplementation may also be of benefit to injured athletes. Cooke et al [ 41 ] observed positive effects of a prior 0.

The authors speculate that creatine ingestion prior to exercise may enhance calcium buffering capacity of the muscle and reduce calcium-activated proteases which in turn minimize sarcolemma and further influxes of calcium into the muscle. In addition creatine ingestion post exercise would enhance regenerative responses, favoring a more anabolic environment to avoid severe muscle damage and improve the recovery process.

In addition, in vitro studies have demonstrated the antioxidant effects of creatine to remove superoxide anion radicals and peroxinitrite radicals [ 42 ]. This antioxidant effect of creatine has been associated with the presence of Arginine in its molecule.

Arginine is also a substrate for nitric oxide synthesis and can increase the production of nitric oxide which has higher vasodilatation properties, and acts as a free radical that modulates metabolism, contractibility and glucose uptake in skeletal muscle.

Other amino acids contained in the creatine molecule such as glycine and methinine may be especially susceptible to free radical oxidation because of sulfhydryl groups [ 42 ]. A more recent in vitro study showed that creatine exerts direct antioxidant activity via a scavenging mechanism in oxidatively injured cultured mammalian cells [ 43 ].

In a recent in vivo study Rhaini et al [ 44 ] showed a positive effect of 7 days of creatine supplementation 4 x 5 g CM 20 g total on 27 recreational resistance trained males to attenuate the oxidation of DNA and lipid peroxidation after a strenuous resistance training protocol.

Collectively the above investigations indicate that creatine supplementation can be an effective strategy to maintain total creatine pool during a rehabilitation period after injury as well as to attenuate muscle damage induced by a prolonged endurance training session. In addition, it seems that creatine can act as an effective antioxidant agent after more intense resistance training sessions.

There are two possible theories to explain these effects: 1 Creatine supplementation increases intracellular water content resulting in increased muscle stiffness and resistance to stretch; 2 Neural outflow from the muscle spindles is affected due to an increased volume of the muscle cell. The authors highlight that the active ROM measures were taken immediately after the loading phase and the reduced active ROM may not be seen after several weeks of maintenance phase [ 45 ].

Hile et al [ 46 ] observed an increase in compartment pressure in the anterior compartment of the lower leg, which may also have been responsible for a reduced active ROM. Neurological and cognitive function has also been shown to be improved by creatine supplementation [ 47 , 48 ].

Rawson and Venezia [ 49 ] review the effects of creatine supplementation on cognitive function highlighting that higher brain creatine has been associated with improved neuropsychological performance. Creatine supplementation protocols have been shown to increase brain creatine and phosphocreatine contents.

Cognitive processing hindered due to sleep deprivation and natural impairment due to aging can be improved by creatine supplementation. This review also highlights other possible benefits of creatine ingestion to older adults, such as improvements in: fatigue resistance, strength, muscle mass, bone mineral density, and performance of activities of daily living. Some of these benefits occur without concurrent exercise. However, the ideal dose of creatine to maximize brain uptake is not known.

Patients have been supplemented with 40 g while in healthy adults positive results have been reported with around 20 g per day [ 49 ]. Studies with animal and cellular models demonstrated positive effect of creatine ingestion on neurodegenerative diseases. These effects have been attributed to improved overall cellular bioenergetics due to an expansion of the phosphocreatine pool [ 50 ]. Creatine deficiency syndromes, due to deficiency of glycine amidinotransferase and guanidinoacetate methyltransferase, can cause decreases or complete absence of creatine in the central nervous system.

Syndromes of this nature have the possibility to be improved by supplementing orally with creatine. Brain creatine deficiency resulting from ineffective crea T1 has been shown not to be effectively treated with oral creatine supplementation [ 51 ].

Additionally, oral creatine administration in patients with myopathies has shown conflicting results depending on the type of myopathy and creatine transport systems disorders [ 4 ]. In a report [ 52 ] conducted on pupils from middle and high school aged 10 — 18 in Westchester County USA 62 of the pupils surveyed were using creatine. The authors found this concerning for 2 main reasons: firstly, the safety of creatine supplementation is not established for this age group and is therefore not recommended.

Secondly, it was speculated that taking creatine would lead on to more dangerous performance enhancing products such as anabolic steroids. It is important to point out that this potential escalation is speculation. Furthermore, a questionnaire was used to determine creatine use amongst this age group and does not necessarily reflect the truth.

Due to this, creatine supplementation may benefit the rate and use of creatine phosphate and ATP rephosporylation. However, performance in short duration high-intensity exercise can be improved through training therefore supplementation may not be necessary [ 54 ].

Based on the limited data on performance and safety, some authors have not identified any conclusions and do not recommend its consumption in regards to creatine supplementation in children and adolescents [ 52 , 54 ]. Research also indicates that creatine may 5 , 27 , 43 , 44 , 45 , 46 , 47 , 48 :. Creatine may combat high blood sugar and fatty liver disease, as well as improve muscle function in older adults.

The most common and well-researched supplement form is called creatine monohydrate. Many other forms are available, some of which are promoted as superior, though evidence to this effect is lacking 1 , 7 , Creatine monohydrate is very cheap and is supported by hundreds of studies. Until new research claims otherwise, it seems to be the best option. The best form of creatine you can take is called creatine monohydrate, which has been used and studied for decades.

Many people who supplement start with a loading phase, which leads to a rapid increase in muscle stores of creatine. To load with creatine, take 20 grams per day for 5—7 days. This should be split into four 5-gram servings throughout the day 1. Absorption may be slightly improved with a carb- or protein-based meal due to the related release of insulin Following the loading period, take 3—5 grams per day to maintain high levels within your muscles.

As there is no benefit to cycling creatine, you can stick with this dosage for a long time. If you choose not to do the loading phase, you can simply consume 3—5 grams per day. However, it may take 3—4 weeks to maximize your stores 1. Since creatine pulls water into your muscle cells, it is advisable to take it with a glass of water and stay well hydrated throughout the day.

To load with creatine, take 5 grams four times per day for 5—7 days. Then take 3—5 grams per day to maintain levels. Creatine is one of the most well-researched supplements available, and studies lasting up to four years reveal no negative effects 8 , One of the most comprehensive studies measured 52 blood markers and observed no adverse effects following 21 months of supplementing 8.

There is also no evidence that creatine harms the liver and kidneys in healthy people who take normal doses. That said, those with preexisting liver or kidney problems should consult with a doctor before supplementing 8 , 51 , In fact, studies suggest it can reduce cramps and dehydration during endurance exercise in high heat 53 , One study found that creatine supplementation is associated with an increase in a hormone called DHT, which can contribute to hair loss.

More research is needed, but people who are predisposed to hair loss may wish to avoid this supplement Creatine exhibits no harmful side effects. At the end of the day, creatine is one of the cheapest, most effective and safest supplements you can take. It supports quality of life in older adults, brain health and exercise performance. Vegetarians — who may not obtain enough creatine from their diet — and older adults may find supplementing particularly useful.

Creatine has many benefits for health and performance. It can help you gain muscle, increase strength, and improve brain function, to name a few. There are many myths regarding the safety and side effects of creatine. The truth is that creatine is actually very safe. Creatine is a well-studied supplement with proven benefits for high intensity exercise. This article explains how creatine can improve your exercise….

Supplementing with creatine can help you produce more ATP so you can increase your workout intensity , which is especially beneficial for athletic activities involving short, fast, explosive movements. Another benefit of creatine is that creatine itself is a fuel source. In fact, your body's first choice of energy when performing anaerobic activity such as weightlifting is your creatine phosphate stores.

By supplementing with creatine phosphate you will increase these stores, thus giving you more energy for your workouts. There is another anabolic property that creatine holds and this is its ability to hydrate muscle cells.

Plus, when your muscles hold more water, they look bigger and more pumped up. While creatine is most popular with strength athletes, it has a number of other potential effects , such as better brain performance, glucose metabolism, and bone mineral density, that make it a supplement that can benefit everybody.

Many studies have been done on creatine and it has been established to be a safe supplement to take. Ciaran Fairman explains this and other common misconceptions in the article " 6 Side Effects of Creatine: Myths Debunked. Since creatine has only been recently introduced to the market, it is hard to determine whether or not there will be long-term health effects from its use.

However, it must be noted that, to date, there is not one reputable study that shows creatine has any dangerous side effects. It is not necessary to load creatine, but it can help you see results faster. To get the full benefit of creatine you must saturate your muscle cells with it.

Using a small dose 5 grams , saturation will take up to 30 days, depending on the individual's lean body mass. However, by using a loading dosage of grams per day for five days you can quickly saturate your muscle cells, then use a maintenance dosage grams to keep your creatine levels high.

It is not necessary to do so, but it can help. Your body has an internal equilibrium which you can swing in your favor for a duration of time, but over time that equilibrium will eventually swing back. This means that taking excess creatine for a short period of time weeks may temporarily increase your creatine phosphate stores, but after a while your body's feedback mechanisms will likely bring the levels back down to normal.