Featured story July 5, 2014
Creatine: Why Use It? Scientific Support To Back Its Benefits
Those involved in the bodybuilding/strength training world - trainers and athletes alike - would know the importance of proper supplementation. One of the more successful supplements to hit the shelves would be creatine.
In it various forms, which over the years have become more and more advanced, creatine has been recognized by the scientific community and the hard training athlete as a product that delivers on its promise of improved strength and enhanced muscle size.
However, creatine (basically a fuel source for ATP, which is an energy system used for short bursts of power) is a product not without its share of controversy. Creatine has been viewed as a potentially harmful product by some authorities. It has since been shown that if used correctly, it is one of the safer supplements to take. Also, some forms of creatine are thought to be superior to others. This we will discuss later.
What we do know is that creatine works, and works well for the majority of people who use it as a regular part of their sporting/exercise program. In this article we will review creatines benefits, some important studies to back its efficacy, its broader applications, and the populations who will benefit most from its use.
One of the most heavily researched supplements in the history of sports nutrition (over 200 studies to date, over the last decade), creatines efficacy cannot be denied. But exactly what benefits will it provide?
Creatine enhances the body's capacity to perform high intensity work (and assists greater muscle size and performance gains as a result).
Creatine phosphate (creatines high energy molecule form, stored within cells) is used to supply the type 11b muscle fibers (fast-twitch high-glycolytic; the ones that get largest in size) with immediate energy, ensuring these muscles do not prematurely fatigue 6.
This strengthens muscular contraction of these fibers, and helps the athlete to pump out more reps, sprint at a faster rate, or engage more forcefully in whatever sport or type of exercise they take part in. Supplementing with creatine allows the muscles to store more of this high-energy molecule to provide greater gains in strength and muscle.
Creatine used in this manner is regarded as a high-energy phosphate, and its role in energy production cannot be overstated. Whenever the body uses energy, a molecule called ATP (an adenosine with a tail of three phosphate groups, hence its name Adenosine Tri Phosphate) is used as an energy source - as a fundamental energy donor.
Under conditions of strenuous activity, ATP releases one of these high-energy phosphate groups to power muscular contraction. Once this phosphate has been released, ATP becomes ADP (Adenosine Di-Phosphate, a de-energized form of ATP). To regenerate ATP and assist further energy production - to complete additional reps for example - creatine becomes a key player.
In fact, without creatine, energy production during high-intensity bouts of exercise would not be possible. Supplemental creatine has been shown to further enhance this process, a fact not lost on the scores of athletes who depend on it to enhance their performance.
For bodybuilders, creatine is of particular significance as it feeds the aforementioned explosive type 11b fibers, thereby increasing power output and subsequently, muscle size.
In recent years creatine has been studied for its post-exercise muscle regeneration properties. Findings have been very promising. In 2004, Santos and colleagues studied the effects of creatine supplementation on muscle cell damage in experienced endurance athletes running a 30-kilometre race12.
Closely monitoring several markers of cell damage (including creatine kinase, lactate dehydrogenase, prostaglandin-E and tumor necrosis factor-alpha) in their sample of 18 male athletes (who used 20 grams of creatine monohydrate per day for five days, mixed with 60 grams of maltodextrine), the researchers found levels of these markers were reduced after the race, compared to 16 control subjects who took only the maltodextrine.
They concluded that creatine supplementation somehow reduced muscle cell damage and inflammation following the exhaustive exercise. The researchers issued the following statement:
It seems creatine also helps to promote complete recovery from intense exercise. Another reason strength and endurance athletes may benefit from its use.
In their impressive study, Ziegenfuss and fellow researchers demonstrated that creatine loading over just three days significantly improved muscle volume and cycle sprint performance in elite power athletes
For this study, ten male and ten female athletes were assigned to creatine or placebo groups, where, before and after the three-day creatine supplementation period, they were assessed on repeated sprint performance and thigh muscle volume - the creatine group was given 0.35 grams of creatine per kilogram of fat free mass, and all subjects completed six maximal ten second cycle sprints with 60 seconds of recovery in between.
It was found that over the three-day period, creatine subjects experienced increased total body mass of, on average, 0.9 kilograms, a 6.6% increase in thigh volume (in five of six creatine taking participants), and increases in performance in all six sprints. Their anaerobic capacity clearly had improved with the addition of creatine, compared to the control subjects who took in only maltodextrin.
Another important benefit for bodybuilders and strength athletes is creatines muscle volumizing effect 3. Creatine has a property that causes muscle cells to inflate, which produces a more heavily muscled appearance, and, more importantly, serves as a stimulus for protein synthesis.
Up to six pounds of added bodyweight in the first few weeks is commonly reported in those who begin creatine supplementation (a process primarily accounted for by water moving rapidly from the bloodstream to the muscle).
As explained previously in this article, creatine's erogenic actions work to assist energy production and power output, resulting in muscle size and strength, and improved performance. Additionally, it has been found creatine provides a powerful anabolic boost through its enhancing of systemic methylation (the regulation of gene expression, protein synthesis and RNA metabolism through enzymatic catalyzation) status 14.
Indeed, methylation is a process that is essential for the supporting of life itself. A molecule known as SAM (S-Adenosyl Methionine) is the body's principal methyl donor, and a breakdown in its production can adversely affect whole-body anabolism.
Creatine drains the body's SAM reserves like nothing else, which, in turn, deleteriously impacts methylation status (during its synthesisation by the liver and kidneys, creatine draws heavily from the SAM reserves). Supplementing creatine will enhance methylation status, as it will lessen the drain on the liver and kidneys, and alleviate the body's need to synthesize creatine from amino acids.
Widely known for it muscle-building benefits, creatine, it appears, has much more to offer than its erogenic properties. Researchers Wyss and Schulze looked at the broader health implications of creatine as they tried to determine its value in treat[ing] several neurodegenerative, vascular and muscular disorders 15.
Their findings, published in the prestigious Neuroscience, showed creatine to be an extremely important neuroprotectant (an agent that increases the survival of nerve cells to environmental insults).
Energy metabolism and the production of Reactive Oxygen Species (very small molecules that can result in significant damage to cell structures, of which include oxygen ions, free radicals and peroxides) are thought to underpin many nuerodegenerative disorders, and creatine is thought to enhance the brains ability to survive the metabolic and physical trauma associated with these conditions.
It was found by Wyss and colleagues that those with neurodegenerative disorders associated with creatine deficiencies (inborn errors in creatine production and storage) may require supplemental creatine, in order for it to be more effectively delivered to the central nervous system.
Additionally, Ray and colleagues found creatine to improve brain function (specifically short-term memory) in normal subjects 11. In a placebo controlled cross-over design study, 45 vegetarian and vegan subjects (chosen as their intake of creatine was negligible) took five grams per day of creatine for six weeks.
After this period, all subjects were assessed on non-verbal intelligence and verbal memory capacity. It was found that subjects who took creatine rather than the placebo exhibited improved short-term memory, and were better able to problem solve under time constraints. Significantly, the researchers said:
Gerbin and co-researchers at the Institute of cell biology in Switzerland found creatine could be used successfully as an adjuvant therapy for bone fracture healing or for the treatment of osteoporosis 7. Based on their in-vivo study, they concluded that creatine significantly enhanced the activity of alkaline phosphate (ALP; an important marker for bone growth).
Cell energy (of which in their study on bone regeneration creatine played a major role) is important for bone development and maintenance, and therefore directly related to osteoporosis. Creatine, as we know, enhances cellular energy production. The researchers linked this to bone formation.
Creatine might assist with the combating of diabetes, as it has been shown to improve glucose tolerance. Derave and co-researchers showed that supplemental creatine increased glucose transporter (glut-4) expression and muscle glycogen content while improving glucose tolerance in a previously immobilized limb 5.
Since this study was conducted, it appears the reasons for the improvements in glucose tolerance were due to the increased expression of glucose transporter type 4. It seems the expression of this transporter was actually induced by IGF-1 and IGF-2, which are induced by creatine.
As we age there is a natural decline in the production of muscle building (anabolic) hormones such as testosterone, growth hormone and the insulin like growth factors (IGF-1). As a result there is a natural tendency for those advancing in age to progressively lose muscle mass.
As mentioned, fast twitch fibers (the type that make the bulk of our muscle size) respond well to supplemental creatine in the athletic population. These fibers are also the first to be sacrificed by the effects of sarcopaenia. The powerful anabolic hormone, IGF-1, has been shown to localize in the fast twitch fibers and, significantly, this is the hormone most likely to dwindle to a greater degree as we age.
It follows that creatine supplementation into older adulthood might negate the degenerative effects of age related muscle wasting as it enhances fast twitch muscle fiber integrity, and, in turn, should help to maintain youthful levels of IGF-1.
At least this is the possibility researcher's Louis and colleagues found when they studied creatines effects on IGF-1 and ageing 10. Other researchers postulate that the muscle volumizing effect of creatine might switch on a gene responsible for IGF-1 production.
Further research suggests advanced systemic methylation (discussed earlier) resulting from creatine use might predispose the cell for greater IGF-1 production. Which of these might prove to be the most efficient means of reducing age related muscle wasting is up for debate, but creatines potential as a muscle preserver in the aging population cannot be denied.
Creatine has also been shown to improve isometric strength in addition to body composition in older adults, provided a strength-training program is run concurrently 1. In their double blind study, Brose and colleagues assigned 28 healthy men and women - over age 65 - to a 14 week resistance training exercise program, during which these subjects trained three days a week.
14 of these participants were given five grams of creatine mixed with two grams of dextrose while the other 14 subjects received a placebo of seven grams of dextrose. After the 14 weeks, the creatine group were found to have experienced greater increases in fat free mass and total body mass, in addition to improvements in isometric knee extension strength.
This study helps to confirm the role creatine can play in offsetting age related muscle wasting, if combined with a strength training regime.
Traditionally a group with lower creatine levels compared to their meat-eating counterparts, vegetarians stand to miss out on the benefits creatine supplies, unless of course they supplement, it appears. It was also thought that given vegetarians initial low creatine levels, they would be more sensitive to its erogenic effects.
Researcher Burke and his co-workers studied this proposal when they compared the changes in muscle creatine, muscle fiber morphology, body composition, hydration status, and exercise performance between vegetarians and non-vegetarians over an eight-week resistance-training program, in which, in double blind fashion, ten vegetarians took creatine and eight took a placebo 2.
Additionally, 12 non-vegetarians took creatine with the other 12 taking the placebo. The creatine-taking subjects initially loaded with 0.25 grams of creatine per kilogram of lean body mass for seven days, before 0.0625 grams over the subsequent 49-day period.
It was revealed that vegetarian subjects who took creatine experienced a greater increase in total creatine, phosphocreatine, lean tissue, and total work performance compared to the non-vegetarians who took creatine, indicating vegetarians are more responsive to creatine supplementation.
Overall, researchers have found that creatine will provide the following benefits:
In light of the above benefits, populations most likely to experience creatines positive effects are: