2. What's your training like? Are you crushing 25 sets for chest like the average juiced out bodybuilder? If so, there's a pretty good chance you might be working above your MRV (maximal recoverable volume) and as such any physiological adaptation which could have taken place is going to be minimal given the cellular environment which occurs in a state of functional overreaching.
Branched-chain amino acids (leucine, isoleucine, valine) play important roles in muscle building. Some researchers have found that following exercise, the branched-chain amino acids, especially leucine, increase the rate of protein synthesis and decrease the rate of protein catabolism (Blomstrand, 2006). The billion dollar supplement industry has been quick to respond; leucine supplements are widely available in health food stores, with a cost upwards of $50 per container. However, because the research findings are inconsistent and little is known about the safety of these products, the American Dietetic Association (soon to be renamed the Academy of Nutrition and Dietetics) advises against individual amino acid supplementation and protein supplementation overall (Rodriquez, 2009). It may be that food sources of these proteins and amino acids provide the same effect for a small fraction of the cost.
Older women with knee osteoarthritis given supplemental creatine at 20g for five days followed by 5g for the rest of the twelve week trial experienced improvements in stiffness (52% reduction), pain (45%), and physical function (41%) as assessed by WOMAC, despite no improvements in physical power output relative to placebo.[425] This study paired supplementation and placebo with a mild exercise regimen.[425]
Increasing creatine levels in skeletal muscle to 687% of baseline (0.5mM creatine, thought to be equivalent to 5g creatine[135]) doesn’t seem to per se increase glucose uptake, but increases glucose oxidation (140% of baseline)[341] which is due to a two-fold increase in the activity of α1 and α2 subunits of AMPK, a potency comparable to 1mM of the reference drug AICAR.[341] Glucose uptake associated with AMPK has indeed been noted in diabetic people who are undergoing physical exercise[342] and in contracting skeletal muscle cells,[153][330] but according to rat[343][344][345] and in vitro studies of cells not being contracted,[341] this is not a per se effect of non-exercising tissue but an augmentation of exercise-induced glucose uptake.
Cribb et al (2007) [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 0.1 g/kg/d of creatine, 1.5 g/kg/d of protein and carbohydrate compared with protein alone or a protein carbohydrate supplement without the creatine. 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 amount of creatine consumed in the study by Cribb et al was greater than the amount typically reported in previous studies (a loading dose of around 20 g/d followed by a maintenance dose of 3-5 g/d is generally equivalent to approximately 0.3 g/kg/d and 0.03 g/kg/d respectively) and the length of the supplementation period or absence of resistance exercise may explain the observed transcriptional level changes that were absent in previous studies [30,31].
Creatine pyruvate (also known as creatine 2-oxopropanoate) in an isomolar dose relative to creatine monohydrate has been shown to produce higher plasma levels of creatine (peak and AUC) with no discernible differences in absorption or excretion values.[83] The same study noted increased performance from creatine pyruvate at low (4.4g creatine equivalence) doses relative to citrate and monohydrate, possibly due to the pyruvate group.
Ghost Size takes the cake for muscle growth. The key to this formula is epicatechin, an antioxidant found in chocolate and certain plants that is linked to a wide array of benefits. These include increased nitric oxide produciton, better oxygenation to the brain, and muscle growth: epicatechin appears to inhibit myostatin, which suppresses muscle growth, and the dosage found in Ghost Size is in line with studies that examined this effect.

Zinc is important to produce the male hormone testosterone and in building the immune system. Magnesium is an essential component of the nervous system and for maintaining heart health. Both have a range of important biochemical function. Zinc and magnesium are often marketed to bodybuilders in combination in a supplement called ZMA. Zinc is in whole grains, seeds, nuts and particularly meat and oysters. After years of research, no evidence exists to show that either mineral offers bodybuilding or athletic performance enhancement in excess of the recommended dietary requirements.
Mitochondrial myopathies are a subgroup of mitochondrial cytopathies in which the skeletal muscle is negatively influenced. They are characterized by weaknesses in muscular function and energy metabolism.[547] These particular myopathies are thought to benefit from creatine supplementation, since creatine can help with some of the dysregulated energy production.[548]
The majority of studies focusing on creatine supplementation report an increase in the body’s’ creatine pool [15-17]. 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. The creatine supplementation protocol consisted of a weeklong loading period of 25 g/d followed by a 5 g maintenance dose for the remainder of the training. 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.
The use of bodybuilding supplements has risen by ten folds. Gone are the times when bodybuilders worked out and consumed nutritious foods to supplement their body. The effect is pretty clear in both the cases. While professional body builders building a natural body remained in shape even after quitting the gym, people who depended on heavy supplements have been found to only lose the shape but also go through premature ageing. The best thing, however, is to eat proper food and take supplements too, which is what bodybuilders usually do. Here are some pros and cons of using bodybuilding supplements.

Creatine supplementation in the under 18 population has not received a great deal of attention, especially in regards to sports/exercise performance. Despite this, creatine is being supplemented in young, <18 years old, athletes [52,53]. In a 2001 report [52] conducted on pupils from middle and high school (aged 10 – 18) in Westchester County (USA) 62 of the 1103 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.
Always consult your doctor before you begin taking a creatine supplement to make sure that there are no negative interactions with whatever diabetes medication you are on. If they deem you to be safe to take creatine, we recommend this unflavored powder from MET-Rx. It’s made without artificial sweeteners, flavors, and colors, so it's just pure creatine monohydrate powder to promote increased muscle strength. One reviewer noted the product is easy to mix and another said the formula was effect for their needs.
In addition to the HIIT sessions, it’s always a good idea to go for a 30–60-minute walk as many days per week as you can. I recommend getting a minimum of 10,000 steps every day. Use a phone app to track them. If you’re into jogging, swimming, hiking, or some other form of long-duration, fairly low-intensity cardio, that is fine to do as well, and as often as you like.
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.

In natural contests, the testing protocol ranges among organizations from lie detectors to urinalysis. Penalties also range from organization to organization from suspensions to strict bans from competition. It is also important to note that natural organizations also have their own list of banned substances and it is important to refer to each organization's website for more information about which substances are banned from competition. There are many natural bodybuilding organizations; some of the larger ones include: MuscleMania, Ultimate Fitness Events (UFE), INBF/WNBF, and INBA/PNBA. These organizations either have an American or worldwide presence and are not limited to the country in which they are headquartered.


This period also saw the rise of anabolic steroids in bodybuilding and many other sports. In bodybuilding lore, this is partly attributed to the rise of "mass monsters", beginning with Arnold Schwarzenegger, Sergio Oliva, and Lou Ferrigno in the late 1960s and early 1970s, and continuing through the 1980s with Lee Haney, the 1990s with Dorian Yates, Ronnie Coleman, and Markus Rühl, and up to the present day. Bodybuilders such as Greg Kovacs attained mass and size never seen previously but were not successful at the pro level. Others were renowned for their spectacular development of a particular body part, like Tom Platz or Paul Demayo for the leg muscles. At the time of shooting Pumping Iron, Schwarzenegger (while never admitting to steroid use until long after his retirement) said that "you have to do anything you can to get the advantage in competition".[citation needed] He would later say that he does not regret using anything.[8]

Carducci, C., Birarelli, M., Leuzzi, V., Carducci, C., Battini, R., Cioni, G., and Antonozzi, I. Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies. Clin Chem 2002;48(10):1772-1778. View abstract.


Increasing creatine levels in skeletal muscle to 687% of baseline (0.5mM creatine, thought to be equivalent to 5g creatine[135]) doesn’t seem to per se increase glucose uptake, but increases glucose oxidation (140% of baseline)[341] which is due to a two-fold increase in the activity of α1 and α2 subunits of AMPK, a potency comparable to 1mM of the reference drug AICAR.[341] Glucose uptake associated with AMPK has indeed been noted in diabetic people who are undergoing physical exercise[342] and in contracting skeletal muscle cells,[153][330] but according to rat[343][344][345] and in vitro studies of cells not being contracted,[341] this is not a per se effect of non-exercising tissue but an augmentation of exercise-induced glucose uptake.
Weight training is primarily an isotonic form of exercise, as the force produced by the muscle to push or pull weighted objects should not change (though in practice the force produced does decrease as muscles fatigue). Any object can be used for weight training, but dumbbells, barbells, and other specialised equipment are normally used because they can be adjusted to specific weights and are easily gripped. Many exercises are not strictly isotonic because the force on the muscle varies as the joint moves through its range of motion. Movements can become easier or harder depending on the angle of muscular force relative to gravity; for example, a standard biceps curl becomes easier as the hand approaches the shoulder as more of the load is taken by the structure of the elbow. Originating from Nautilus, Inc., some machines use a logarithmic-spiral cam to keep resistance constant irrespective of the joint angle.
The 100% Grass-Fed Whey Protein Isolate comes in the form of powder and can be mixed with any liquid. While the protein powder can be mixed well with water, try mixing it with milk for added calories and protein. You can even add this to smoothies and baked goods to increase the protein profile. Recommended protein intake for adults is 0.8 grams per kilogram. Some athletes may need as much as 1.2-2 grams protein per kilogram. For your specific needs, always consult a registered dietitian.
These protective effects are similar to those seen with trimethylglycine, since they both cause an increase in liver concentrations of phosphatidylcholine (PC, causing an increase in vLDL production and efflux of triglycerides from the liver).[497] Both TMG and creatine are thought to work indirectly by preserving SAMe concentrations,[125][498] since PC synthesis requires SAMe as well (via PEMT[499]) and genes involved in fatty acid metabolism in the liver that were not affected by the diet (VLCAD and CD36) were unaffected by creatine.[125]

Athletes in ancient Greece were advised to consume large quantities of meat and wine. A number of herbal concoctions and tonics have been used by strong men and athletes since ancient times across cultures to try to increase their strength and stamina.[5] In the 1910s, Eugen Sandow, widely considered to be the first modern bodybuilder in the West, advocated the use of dietary control to enhance muscle growth. Later, bodybuilder Earle Liederman advocated the use of "beef juice" or "beef extract" (basically, consomme) as a way to enhance muscle recovery. In 1950s with recreational and competitive bodybuilding becoming increasingly popular Irvin P. Johnson began to popularize and market egg-based protein powders marketed specifically at bodybuilders and physical athletes. The 1970s and 1980s marked a dramatic increase in the growth of the bodybuilding supplement industry, fueled by widespread use of modern marketing techniques and a marked increase in recreational bodybuilding.
my name is Samtak and i recently started experimenting with some supplements after about 4-6 months of working out. as of right now i have a protein shake once a day with gainers in the protein powder and am trying to figure out how to use beta alanine and creatine in combination with BCAA. Can anyone help me figure out how to set out a good plan for better effects from these supplements? my current weight is 60 kg and i am 16
Creatine kinase is expressed in eyes. The eyes can take creatine up from the blood via two different transporters, the classic SCL6A8 (creatine transporter) and MCT12. It seems that expression of the receptors and accumulation of creatine occur in a relatively higher level in photoreceptors, which perceive color. Similarly to many other tissues, they appear to protect the cells during periods of low oxygen availability.
Without supplementation, approximately 14.6mmol (2g) of creatinine, creatine’s urinary metabolite, is lost on a daily basis in a standard 70kg male ages 20-39. The value is slightly lower in females and the elderly due to a presence of less muscle mass.[35] This amount is considered necessary to obtain in either food or supplemental form to avoid creatine deficiency. Requirements may be increased in people with higher than normal lean mass.[35][198] Creatine excretion rates on a daily basis are correlated with muscle mass, and the value of 2g a day is derived from the aforementioned male population with about 120g creatine storage capacity.[35] Specifically, the rate of daily creatine losses is about 1.6%[199]-1.7%,[25] and mean losses for women are approximately 80% that of men due to less average lean mass.[35] For weight-matched elderly men (70kg, 70-79 years of age) the rate of loss of 7.8mmol/day,[49] or about half (53%) that of younger men.

A meta-analysis of 16 studies conducted on creatine and its influence on power and strength,[368][369] (with or without exercise in all age groups above 16, but placebo controlled and without crossover[368]) compiled studies utilizing a 5-7 day loading period with continued maintenance thereafter and studies assessing 1-3 rep bench press strength in trained young men. Seven studies (four of which are online[370][371][372][373]) totaling 70 people using creatine and 73 people in placebo showed a 6.85kg increase in strength relative to placebo, the benefits of which peaked at 8 weeks.[368] This meta-analysis also quantified a significant increase in squat strength (9.76kg) yet failed to find a significant influence on peak bicep contraction power, which may have been influenced by the two null studies[374][375] being in elderly people while the positive study[376] was statistically outweighed, but noted an 1.8-fold increase in power associated with creatine over placebo. The other meta-analysis conducted the following year[369] calculated effect sizes for creatine supplementation and noted no significant differences between genders or when comparing trained and untrained individuals. The mean effect size of exercises lasting below 30s (those that use the creatine-phosphate system) was 0.24+/-0.02 and performed significantly better than placebo, where exercise increased performance by 4.2+/-0.6% while the addition of creatine enhanced this effect to 7.5+/-0.7%.[369]
Whey Protein: This protein is a product of cheese making. Whey is the watery milk that’s separated and removed from the cheese curd. Through further processing, it’s turned into a powder. Whey protein is a great source of amino acids and nutrients. You can find whey protein from a number of manufacturers in different flavors including vanilla and chocolate.
Creatine is stored in the body in the form of creatine and as creatine phosphate, otherwise known as phosphocreatine, which is the creatine molecule bound to a phosphate group.[39] Creatine phosphate is thought to maintain the ATP/ADP ratio by acting as a high-energy phosphate reservoir.[40] The more ATP a muscle has relative to ADP, the higher its contractility is, and thus its potential strength output in vivo.[41][42] This pro-energetic mechanism also affects nearly all body systems, not just skeletal muscle. [39] During periods of rest and anabolism, creatine can gain a phosphate group through the creatine-kinase enzyme pathway, up to a cellular concentration of 30uM[24] to be later used for quick ATP resupply, when needed.[43][44] 
Parameters of lung function (main cause of death in ALS is declining respiratory function) have not benefited after creatine supplementation, and when quality of life is measured, there is no benefit either. Despite one study failing to find any significant differences in mortality risk, two other studies have suggested that creatine may reduce the risk. The results were nonsignificant, but due to all treatments being well tolerated it is thought that creatine may still play a role as an adjuvant.
Carducci, C., Birarelli, M., Leuzzi, V., Carducci, C., Battini, R., Cioni, G., and Antonozzi, I. Guanidinoacetate and creatine plus creatinine assessment in physiologic fluids: an effective diagnostic tool for the biochemical diagnosis of arginine:glycine amidinotransferase and guanidinoacetate methyltransferase deficiencies. Clin Chem 2002;48(10):1772-1778. View abstract.

It’s true—your genes can play a role when it comes to building muscle. In general, there are two types of muscle fibers: Type I, which are slow twitch, and Type II, which are fast twitch. Depending on which you have more of, you may have an easier or harder time gaining muscle. “Fast twitch muscle fibers are two times as thick as slow twitch muscle fibers, lending to the overall thickness of the muscle without any activity,” explains Lovitt. “Those people with a genetic predisposition of a high percentage of these fibers can increase muscle size very easily while the people with a higher percentage of slow twitch muscle fibers have to work really hard to put on mass.” It’s the reason why a world-class sprinter genetically has more fast twitch muscle fibers than a world-class marathoner—it comes down to what we’re born with.
Take time to rest. To give your muscles time to recover, rest one full day between exercising each specific muscle group. You might choose to work the major muscle groups at a single session two or three times a week, or plan daily sessions for specific muscle groups. For example, on Monday work your arms and shoulders, on Tuesday work your legs, and so on.
Naturally produced in the kidneys, pancreas and liver, creatine is transported to muscle tissue where it is transformed into creatine phosphate, from which the energy molecule ATP is produced to regenerate the muscles' ability to contract and generate power during short-burst (anaerobic) activity. This translates to more productive workouts and faster muscle growth.
Weight training has also been shown to benefit dieters as it inhibits lean body mass loss (as opposed to fat loss) when under a caloric deficit. Weight training also strengthens bones, helping to prevent bone loss and osteoporosis. By increasing muscular strength and improving balance, weight training can also reduce falls by elderly persons. Weight training is also attracting attention for the benefits it can have on the brain, and in older adults, a 2017 meta analysis found that it was effective in improving cognitive performance.[38]
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Moving through repetitions too quickly, going too fast; there is nothing gained by lifting weights fast. Some of the perks of lifting weight in a slow and controlled manner, include more total muscle tension and force produced, more muscle-fiber activation both slow and fast twitch fibers, and less tissue trauma. Remember, a joint is only as strong as the muscles that cross it; if you haven't lifted in a long time, or ever, be careful what you ask of your joints.
It is known that intracellular energy depletion (assessed by a depletion of ATP) stimulates AMPK activity in order to normalize the AMP:ATP ratio,[333][334] and when activated AMPK (active in states of low cellular energy[335] and colocalizes with creatine kinase in muscle tissue[336]) appears to inhibit creatine kinase via phosphorylation (preserving phosphocreatine stores but attenuating the rate that creatine buffers ATP). While phosphocreatine technically inhibits AMPK, this does not occur in the presence of creatine at a 2:1 ratio.[334] It seems that if the ratio of phosphocreatine:creatine increases (indicative of excess cellular energy status) that AMPK activity is then attenuated, since when a cell is in a high energy status, there is less AMP to directly activate AMPK.[334][336][337]

In patients with DM1 given a short loading phase (10.6g for ten days) followed by a 5.3g maintenance for the remainder of an 8-week trial noted that supplementation resulted in a minor improvement in strength (statistical significance only occurred since placebo deteriorated) and no significant difference was noted in self-reported perceived benefits.[565] Maintaining a 5g dosage for four months also failed to significantly improve physical performance (handgrip strength and functional tests) in people with DM1, possible related to a failure to increase muscular phosphocreatine concentrations.[566]
Creatine is an energy substrate: a small peptide serving as a reservoir for high-energy phosphate groups that can regenerate ATP, the main currency of cellular energy. An increase in creatine intake (through food or supplementation) increases cellular energy stores, promoting the regeneration of ATP in the short term. Stores are limited, however, and glucose or fatty acids are responsible for ATP replenishment over longer durations.
Those 5-pound dumbbells were a great place to start as a beginner, but if you've been lifting weights for a while, it's time to bump up the weight. “You can use both exercise machines and free weights,” explains Michele Olson, PhD, exercise physiologist, professor of exercise science at Auburn University Montgomery, “but, if you are not lifting heavy enough weight, it doesn’t matter if you are primarily using free weights or machines.” In order to build muscle, you must break down muscle tissue using a weight that is challenging enough to cause micro-tears, which when repaired, form denser, stronger fibers.
Kreider, R. B., Kalman, D. S., Antonio, J., Ziegenfuss, T. N., Wildman, R., Collins, R., … Lopez, H. (2017, June 13). International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. Journal of the International Society of Sports Nutrition, 14(18). Retrieved from https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0173-z
Our Keep-It™ guarantee is valid for the first-time purchase of a formula, and redeemable up to three months (90 days) after the purchase date. Multiple bottles, foods, apparel and gear do not fall under this guarantee, however, they may be applicable for return. Fitness equipment, personal care products, knowledge purchases, and DVDs are not eligible for return or refund. For more information and a full list of products that qualify, visit our Keep-It™ page. Further details can be found on our Refund Policy support page.
Kilduff, L. P., Georgiades, E., James, N., Minnion, R. H., Mitchell, M., Kingsmore, D., Hadjicharlambous, M., and Pitsiladis, Y. P. The effects of creatine supplementation on cardiovascular, metabolic, and thermoregulatory responses during exercise in the heat in endurance-trained humans. Int J Sport Nutr Exerc Metab 2004;14:443-460. View abstract.
Researchers described the study as one of the first to examine how strength training can reduce the risk of cardiovascular disease, separate from the effects of aerobic activity like running or long walks. The point: for those who are not meeting recommended guidelines for aerobic activity—perhaps because they lack the time—bursts of weight training can be enough.
It can be hard to know where to start when beginning strength training. There are countless exercises you can do, some of which work some muscles, but not others. There are safety concerns to beware of, a wide variety of sometimes confusing equipment to help you in your efforts, and so on. With some familiarity of the basics of getting started with strength training, actually doing so can become far less daunting, and you can begin to craft a routine that is targeted toward helping you achieve your personal goals.

Creatine supplementation appears to augment the anti-cancer effects of Vitamin C and methylglyoxal,[463] a metabolic by-product of glycolysis.[464] Methylglycoxal appears to inhibit step 1 of the electron transport chain in isolated mitochondria and cancerous mitochondria, but has not been implicated in doing so in normal tissue, as protective measures in normal cells appear to exist.[465][464]


Cornelissen, V. A., Defoor, J. G., Stevens, A., Schepers, D., Hespel, P., Decramer, M., Mortelmans, L., Dobbels, F., Vanhaecke, J., Fagard, R. H., and Vanhees, L. Effect of creatine supplementation as a potential adjuvant therapy to exercise training in cardiac patients: a randomized controlled trial. Clin.Rehabil. 2010;24(11):988-999. View abstract.
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Creatine concentration is normally increased in the placenta and brain in the midgestation phase until term, with further increases in the brain for another two weeks after birth.[529] This effect appears to be due to the fetus itself expressing the creatine enzymes of synthesis (AGAT and GAMT) after 5% of the gestation time has passed (0.9 days in spiny mice).[529] Despite creatine normally suppressing AGAT when supplemented at high concentrations,[29][30] it appears that maternal supplementation of the diet with 5% creatine from the halfway point of pregnancy until term does not alter creatine synthesis in the newborn (no alterations in either AGAT or GAMT), nor does it affect the creatine transporter.[530] 
Without supplementation, approximately 14.6mmol (2g) of creatinine, creatine’s urinary metabolite, is lost on a daily basis in a standard 70kg male ages 20-39. The value is slightly lower in females and the elderly due to a presence of less muscle mass.[35] This amount is considered necessary to obtain in either food or supplemental form to avoid creatine deficiency. Requirements may be increased in people with higher than normal lean mass.[35][198] Creatine excretion rates on a daily basis are correlated with muscle mass, and the value of 2g a day is derived from the aforementioned male population with about 120g creatine storage capacity.[35] Specifically, the rate of daily creatine losses is about 1.6%[199]-1.7%,[25] and mean losses for women are approximately 80% that of men due to less average lean mass.[35] For weight-matched elderly men (70kg, 70-79 years of age) the rate of loss of 7.8mmol/day,[49] or about half (53%) that of younger men.
Chwalbinska-Monteta [34] observed a significant decrease in blood lactate accumulation when exercising at lower intensities as well as an increase in lactate threshold in elite male endurance rowers after consuming a short loading (5 days 20 g/d) CM protocol. 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. Thompson et al [36] reported no effects of a 6 week 2 g CM/d in aerobic and anaerobic endurance performance in female swimmers. 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.
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