Creatine

The wonder supplement

By Xavier Fox

Unless you have been living in a cave on a remote island near Antarctica, it is probably safe to assume that you have heard of creatine. Creatine may just be more used and researched than any other performance-enhancing supplement in sporting history. Although it is most popular among the iron crowd, creatine is not just a supplement for hard-core weight lifters. It does not matter if you are into resistance training or endurance activities, or if you are male or female, young or old, creatine is a supplement that will enable you to maximize your athletic potential and physical well-being. This supplement is widely used in both the amateur and professional ranks of various athletics around the globe.

Unlike most supplements used by athletes, creatine is neither a vitamin, mineral, herb or hormone. It is an amino acid that occurs naturally in our body. Its chemical name is methyl guanidine-acetic acid.
The majority of creatine (about 95%) is located in the skeletal muscle system. The remaining 5% is in the brain, heart and testes. We acquire most of the creatine in our system by consuming meat and fish, as well as dairy products, egg whites, nuts and seeds.
Although the human body has a way of storing very high amounts of creatine to enhance recovery and muscle power, you would find it almost impossible to consume enough food to get as much creatine as you could in one scoop of the average creatine powder. If you are deficient in creatine, your body can synthesize it from the amino acids arginine, glycine and methionine as long as they are available. This manufacturing process takes place in the kidneys, liver and pancreas.
The most sought after benefit of creatine is its ability to aid in energy production. When ATP (adenosine triphosphate) loses one of its phosphate molecules and becomes ADP (adenosine diphosphate), it must be converted back to ATP in order for the molecule to be able to produce energy again. The creatine in our body is mostly stored as creatine phosphate (known as phosphocreatine) and will donate its phosphate to the ADP, renewing the ATP molecule so it can then produce energy.
ATP is the form of energy used by the muscles in anaerobic activity (explosive movements that occur too fast to use oxygen as energy). By using a creatine supplement, an athlete has access to an abundance of creatine phosphate in their cells, allowing for rapid replenishment of ATP. This leads to a readily available energy source so the muscle is able to replenish its energy much faster and do more work in less time.
The conversion of ADP to ATP takes place inside the mitochondria. The mitochondria are where cellular respiration takes place, which is the process that generates the fuel our cells use as energy.
There are three steps in the process of cell respiration: glycolysis, the Krebs cycle (the citric acid cycle) and the electron transport chain.
When we consume food, it goes through a process and gets oxidized in order to produce high-energy electrons. These high-energy electrons get stored in the phosphate bonds of ATP. When these bonds are broken, the ATP gives up a phosphate and energy is released for use by the cell. This is accomplished by hydrolysis, which is when the addition of a water molecule splits the ATP into simpler molecules. In order for the newly formed ADP molecule to be able to produce energy again, it must bond with an available phosphate and reform the ATP containing the high-energy bonds.
During glycolysis, a 6-carbon sugar is broken down into two 3-carbon sugars known as pyruvic acid. These molecules of pyruvic acid play an important role during the Krebs cycle and the production of energy. Four ATP molecules are produced during glycolysis, but two of them are expended during other steps. Glycolysis is actually the first step in both the aerobic and anaerobic energy production process. It does not require oxygen during its chemical reactions.
The pyruvic acid formed during glycolysis is later fully broken down into carbon dioxide (CO2) allowing for even more energy to be released. Three molecules of O are required so they can react with each molecule of pyruvic acid and form three carbon dioxide molecules. In addition, three hydrogen atoms will combine with oxygen to form water. Each molecule of pyruvic acid contains three carbon atoms. While one carbon is used when carbon dioxide is formed, the remaining two carbons are transferred to a molecule called acetyl coenzyme A. For every molecule of acetyl coenzyme A that is produced, it is broken down with two molecules of ATP as one of its products.
As the cell respiration process continues, the Krebs cycle and Electron Transport Chain continue to produce more ATP until a total of 40 molecules of ATP have been created. This entire process occurs within the mitochondria.
The cell respiration process is extremely complex and there are many reactions going on simultaneously. One process taking place during glycolysis and the Krebs cycle is the release of electrons. The cell stores these electrons and forms a compound known as Nicotinamide Adenine Dinucleotide (NADH). This compound is used to carry electrons to the electron transport chain so that the electrons can be used to create more energy. In addition, a molecule known as flavin adenine dinucleotide (FAD) combines with two hydrogens and two electrons to form FADH₂ .
The electron transport chain is a system of electron carriers inside the mitochondria that pass electrons from one compound to the next. For every molecule of NADH that is formed, it will donate two electrons allowing the formation of three molecules of ATP. FADH2 only allows for the formation of two molecules of ATP. It is believed that these electrons cause the “pumping” of positively charged hydrogen atoms across the inner membrane of the mitochondria which creates the energy required to synthesize ATP. In the last step of the electron transport chain, some of these hydrogen atoms combine with oxygen to form water.
As you can see, the cell respiration process is how energy is produced within the cell and ATP has a vital role in that process. Having phosphate readily available is very important if you wish to be able to keep high levels of energy accessible to the muscle. By supplementing with creatine, you can ensure that you will have the phosphate levels required to make you last through intense workouts.
There is evidence that creatine can stimulate muscle growth. It does this in a couple of different ways. By allowing you to perform more work as a result of additional energy, increased protein synthesis is stimulated. Secondly, when an abundance of creatine phosphate is stored in the muscle, the muscle will hold more water in its cells and become what is known as “volumized” or “super-hydrated”. The more volumized a muscle is, it will promote the synthesis of protein as well as deter the breakdown of protein. Volumizing the muscle will also create an environment where an increased level of glycogen synthesis will take place. Increased protein synthesis along with training will lead to muscle growth. There is also scientific evidence that creatine supplementation leads to faster repair of muscle tears.
During resistance training, the glycogen breakdown process has a side effect - development of lactic-acid. This substance is responsible for the intense burn felt during exercise and muscle fatigue. Creatine phosphate acts as a ‘buffer’ to lactic acid build-up.
As mentioned earlier, creatine phosphate aids in the production of ATP. This process consumes large amounts of hydrogen ions which are released by lactic acid and can build up in muscle cells during intense exercise. These excess hydrogen ions interfere with muscle contractions, but creatine phosphate’s ‘buffering’ action helps to delay fatigue, allowing for longer workouts.
Studies suggest creatine has the ability to increase growth hormone levels in your system. In this research, subjects consumed 20g per day of creatine and their blood GH levels showed a statistically significant increase of GH for 2-6 hours after the creatine ingestion. It is important to note that these subjects did not exercise or consume any other type of supplement that could influence a natural elevation in growth hormone levels. The scientists concluded that the increase in blood levels of GH was due solely to the consumption of creatine.
Science has proven that as we age, our bodies produce less growth hormone. This is why we have more physical-related problems as we age, such as loss of muscle mass, fragile bones, less elastic skin, that we get sick more often and do not have the energy we once had.
Through its ability to enhance GH levels, creatine can offer aging health enthusiasts an opportunity to maintain their health as well as their youthful vitality and general well-being. For those elderly individuals feeling the effects of muscle loss as they age, creatine provides a “double-whammy” by volumizing muscle cells as well as increasing growth hormone levels.
So far, we have seen how creatine can enrich the physical well-being of the general athlete and the elderly, but we have not discussed its other benefits for the female population. Of course, creatine will help boost energy levels in the female athlete the same as it does for their male counterparts. However, by aiding the production of muscle mass, creatine also helps female athletes add the muscle they need to improve their performance.
Women generally have a more difficult time trying to gain muscle size and strength than men do. Creatine helps them increase strength much faster. It is well-documented that carrying more muscle causes the body to burn more calories, even at rest. Women who use creatine and add some additional muscle to their frame will burn more calories and body fat throughout the day.
Yet another fantastic property of creatine that benefits people of all ages and abilities is creatine’s ability to lower bad cholesterol in your system. Plaque builds up in your arteries due to the form of cholesterol known as low density lipoprotein (LDL), better known as “bad cholesterol”.
Studies have shown that creatine can reduce cholesterol levels by 15%! If you consider the fact that people with a cholesterol reading of 220 mg/dl are twice as likely to have heart disease as people in the 180 mg/dl range, it is easy to see that 15% can make a huge difference (220 is only 18% more than 180).
In a 1996 study by Dr C. Earnest, creatine supplementation reduced both total cholesterol levels and fatty acids (triglycerides) in the blood. So, this wonder supplement will do more than just pump you up, it will keep your heart pumping as well!
The majority of studies on creatine have been done on athletes performing anaerobic activities. Until recently, has was not much information on how creatine could help endurance athletes.
A recent study at Louisiana State University tested the theory that creatine could benefit endurance athletes by increasing their lactate threshold. Recalling from one of the first paragraphs, when glucose is broken down it creates pyruvic acid. The pyruvic acid will either be transported into the mitochondria with the assistance of an enzyme called pyruvate dehydrogenase, or it will be converted to a waste product known as lactic acid via the enzyme lactate dehydrogenase. As mentioned before, when pyruvic acid goes into the mitochondria it is subject to further enzymatic breakdown, oxidation and a high ATP yield per glucose. If the pyruvic acid gets converted to lactate, then there is halt in the energy production process, and the potential for contractile fatigue increases dramatically, because of the decrease in pH levels as a result of the lactic acid. Whether, or not pyruvic acid converts to lactic acid or ATP is dependent on a few different things.
During exercise, the frequency and duration of your muscle contractions will determine if your body chooses to manufacture ATP by metabolising fatty acids or glucose. If the demand for ATP continues to increase, glucose demands also increase and the amount of pyruvic acid being produced will become high. If your muscle fibre contain a lot of mitochondria, then the pyruvic acid will be more likely to be converted into acetyl coenzyme A and transported into the mitochondria without producing lactate.
During this type of process, fatty acid will be the major compound used to produce the ATP. The rate of glycose transferring through the cell is low and pyruvic acid is transported into the mitochondria for oxidative breakdown when the workload is relatively small.
Slow twitch fibres will do most of the work in this situation. However, as the workload increases and more fibres are needed, ATP demand increases and more pyruvic acid needs to be manufactured. At these higher workloads, large percentages of the pyruvic acid is now converted to lactic acid and fast twitch fibres are starting to be recruited to do work. Lactic acid will flow out of the muscle fibre and into the bloodstream.
As the intensity of the aerobic exercise is increased, more and more muscle fibres must help to meet the requirements of the workload. This means that more and more lactic acid is manufactured and transported into the bloodstream. The body will not only manufacture the lactic acid, but it will also consume it in inactive muscles where it will be converted back into pyruvic acid or used to produce more glucose. (Lactic acid tends to flow from areas of high concentrations to areas of low concentrations.)
If the rate at which the inactive muscles absorb lactic acid can equal the rate at which it is entering the bloodstream, the blood levels of lactic acid will stay constant. When the rate at which lactic acid is produced is greater than the rate it ‘disappears’, then lactic acid will accumulate in the blood stream. This is known as the ‘lactate threshold’.
In endurance athletes, when lactic acid begins to accumulate in the blood, the muscle loses some capacity to contract. This is due to protons being accumulated in the cell. Physical activity that is intense enough to be at the lactic acid threshold can only be sustained for a short time (depending on the level of intensity). If the intensity is below the lactic acid threshold, it is easy to maintain activity. Fatigue onset below the lactic acid threshold is due to carbohydrate depletion and dehydration.
The main variables in lactic acid accumulation are: the level of intensity, the degree of conditioning of the muscle that is training, the type of fibre performing the work (fast twitch or slow twitch), the distribution of the workload on the muscles (smaller muscles versus larger ones), and the rate that lactate is cleared from the blood.
These are the things that will affect your lactate threshold and determine your muscles endurance. The lactate threshold is both responsive to training and influenced by genetics.
The previous information on lactate threshold brings us back to the research at Louisiana State University. Traditional studies aimed at increasing an athlete’s endurance will normally pursue ways to increase oxygen flow to the muscle. The researchers at LSU knew that the power of the muscle would play an important role in the muscle’s ability to perform aerobic activity. By using creatine to increase the strength of the muscles, the athletes in the LSU study were able to raise their lactate threshold speed. Since their muscles were much stronger, they needed a lesser amount of muscle fibres to perform the work. Their lactate threshold was raised and they were able to do more work for longer periods of time.
In another study at Kingston University in Surrey, 16 endurance athletes were asked to perform intervals at all-out intensity. They were then divided into groups and one was supplemented with creatine and the other with a placebo.
After five days of taking four 5g serves of creatine per day (20g in total per day), the groups did the intervals again. Then, for four weeks , the athletes did not take any creatine, in order to clean out their system. The interval training and supplementation was performed once again, however this time the groups were switched. In both cases, the group supplementing with creatine was able to do up to 16% more work.
A study performed on endurance cyclists showed that the group supplementing with creatine improved stamina by 23% while the placebo group was unaffected.
It is well-known that most endurance athletes also perform many types of anaerobic training activities to enhance their performance. Creatine will help them during their strength training and some types of intermittent training. Creatine also offers endurance athletes a glycogen sparing effect. This allows for more glycogen retention inside the muscle cells so the athlete can have more to use during activity.
It is clear to see that the endurance athlete can greatly benefit from the use of creatine. Creatine increases the strength and amount of work that a muscle can perform, even during aerobic activity.
As you can see, creatine is a well-rounded supplement that can be of benefit to any athlete and any age group. It has proven to help build muscle, increase strength, prolong endurance and keep growth hormone levels high. Make creatine a part of your supplementation regimen, and you can keep your body youthful and strong. However, use it responsibly and take it only according to the manufacturers instructions. Enjoy those gains!