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The amino acid creatine was discovered in 1835, but only came into public view following the Barcelona Olympics in 1992. The performance of several British athletes exceeded expectations, and it was revealed that they had incorporated creatine supplementation into their nutrition regimen.
Creatine is a nitrogenous compound that is technically an amino acid but not part of body proteins. Rather, it helps in energy metabolism in muscle. Creatine is probably the most researched dietary supplement, as more than 500 papers have been published examining the response to supplemental creatine, generally on exercise performance. The large majority of these studies have shown beneficial effects of creatine on athletic performance.
Creatine is produced in the body, but we also get this amino acid from the foods we eat, such as seafood and red meat. People who have low levels of creatine in their diet, particularly vegetarians, seem to benefit the most from creatine supplementation.
It provides energy for explosive exercises. Creatine is converted to phosphocreatine (CP) in the muscle. CP serves as a source of energy for explosive exertion, such as sprinting or lifting a heavy weight. It provides energy when you are using more ATP than you are regenerating in mitochondria, the energy factories of the cell. The extra supply of energy provided as CP, although quickly used up, is credited with producing greater gains in muscle mass and strength from resistance training, as well as improved performance in explosive sports that last only a matter of seconds, such as sprinting.
It carries energy to where it is needed most. While it has long been recognized that supplementing with creatine can increase the amount of CP in muscle, thereby improving athletic performance in events that require more rapid use of energy than can be supplied by new ATP production, it is less well appreciated that the creatine-phosphocreatine system also acts as an “energy carrier” that makes ATP available to contracting muscles through cellular energy transport from the mitochondria to the site of use in the muscle cell.
Creatine supplementation has been shown to benefit certain athletes. Benefits of creatine may include increased muscle mass and speed of contraction. The extent of beneficial effect depends on how much creatine is consumed in the normal diet and the athlete’s chosen event or sport.
Aging is associated with decreased muscle mass, strength, and function. In athletes, the beneficial long-term effects, such as increased muscle mass, are generally attributed to enhanced training capacity. For example, creatine supplementation may enable you to lift heavier weights, which in turn helps your muscles grow larger. However, in elderly, performing resistance exercise or high-intensity training is often not feasible. A review of the literature indicates that creatine supplementation, even without resistance training, seems to enhance muscular mass, strength, and function in the elderly. Creatine supplementation can also increase bone mineral density in the elderly.
Creatine itself is not used for energy during exercise (like muscle glycogen is), but rather serves to transport energy in the mitochondria to contracting muscles. Therefore, in theory it shouldn’t matter when you take it in relation to a workout—remember that it can have a beneficial effect even without exercise.
A recent paper supports the notion that it is preferable to take creatine after a workout. However, inspection of the data in the paper reveals that taking creatine post-workout really doesn’t make all that much difference. Other researchers have argued that the beneficial effect of creatine supplementation is more pronounced with pre-workout consumption, and still others maintain it doesn’t make a difference. The bottom line is that, if there is so much debate on the best time to take creatine, it probably doesn’t matter WHEN you take it as much as that you DO.
Taking as much as 20 grams of creatine a day or more for five days, and then taking as much as 5 grams per day after that, is often recommended for optimal support of athletic performance. However, such large doses can induce undesirable side effects, including muscle cramping, nausea, diarrhea, gastrointestinal pain, and dehydration.
It is likely that much smaller doses can help to promote muscle growth and improved muscle function over time. The normal daily dietary intake for an omnivorous diet is about 1 gram a day, which is the same amount of creatine that is produced in the body each day. Therefore, a 1-gram dose of creatine would approximately double how much creatine you get on a daily basis from your diet. This increase should be adequate to promote enhanced muscle protein synthesis…if supplemental essential amino acids are provided at the same time.
Whether you’re an athlete looking to maximize performance and muscle gain, or moving into your golden years and looking to increase or maintain muscle strength with age, your success rests on muscle protein synthesis. Activating muscle protein synthesis is how you increase muscle mass and strength, even in the absence of exercise.
The process of muscle protein synthesis requires energy in the form of ATP, as well as amino acids to help build muscle proteins. Creatine given alone can provide extra energy for muscle protein synthesis, but without increased availability of amino acids only a limited amount of new muscle can be produced. This is why results from creatine supplementation can be variable. If adequate amino acids are not available, there can only be minimal stimulation of muscle protein synthesis.
There are 20 different amino acids that make up muscle protein. Nine of these are not produced in the body and are called essential amino acids (EAAs). All of the EAAs are needed, and in relative proportion to the composition of muscle protein, to produce new muscle protein.
An EAA supplement is a powerful stimulus of muscle protein synthesis, but the amount of protein produced will ultimately be limited by how much energy in the form of ATP is ready to go at the site of production of the new muscle protein. This is where creatine comes in—it provides the necessary energy to support an increased rate of muscle protein synthesis. Consequently, there is an interactive effect between EAA availability and the amount of creatine in the muscle.
While creatine supplementation alone cannot produce new muscle protein, extra creatine can enhance the stimulatory effect of supplemental EAAs by providing the extra energy needed for new protein to be produced.
AGING = MUSCLE LOSS = DISEASE ARE YOU AT RISK: LEARN MORE
