Ask any recreational or professional athlete about creatine, and you will be hard pressed to find someone who has not heard of or tried this popular nutritional supplement. Creatine is by far the most highly studied and highly marketed of all sports supplements. Many people have formulated their own opinions about this muscle-building supplement based on anecdotal reports of gym buddies who have "packed on ten pounds of mass in two weeks". In order to debunk the myths and misconceptions surrounding creatine, one must call upon the collective expertise of nutritionists, biochemists, physicians, and exercise physiologists.
Creatine was discovered in 1832 by the French scientist Chevreul as a naturally occurring nonessential amino acid. Physiologists estimate that the body turns over approximately two grams per day, and that skeletal muscle is both the greatest sink and source of dietary creatine. Nutritionists estimate that non-vegetarians consume about one gram per day through their diets. Tuna, salmon, beef, pork, and herring are the most creatine-dense foods, containing between 1.8 and 4.5 grams per pound of food, respectively. Strongmen from the Fifth-century BC were the first to experiment with creatine as they trained by lifting calves and then eating raw beef.
Contrary to popular sentiment, creatine supplementation does not magically pack on pounds of ripped muscle. It does, however, play an important role in energy transformation and exchange within the body, specifically within the phosphagen energy system, and can, along with intense training and solid nutrition, create an anabolic, or muscle-building, environment.
The phosphagen energy system is used exclusively during intense bouts of all-out muscular contractions lasting between five and 10 seconds. Beyond approximately 10 seconds and up to approximately three minutes (football, hockey, sprinting, downhill skiing, weight training, power lifting) the phosphagen system combines with the glycolytic—or anaerobic—energy system to provide fuel for working muscles.
Within the phosphagen system, adenosine triphosphate (ATP) is the main chemical component needed to fuel muscle contractions. ATP stores are limited, and they are reliant upon phosphocreatine (PC) to produce additional ATP molecules. When PC stores are depleted, performance deteriorates. Creatine provides a phosphate group (PC) to help regenerate ATP for further muscle contractions.
A wealth of studies has shown that supplementation with creatine enhances anaerobic athletic performance by increasing single and repetitive sprint performance, increasing total work capacity, increasing strength, and reducing onset of fatigue (Baylor University, 2005). Kreider, et al, has done numerous studies documented in the Journal of Exercise Physiology that creatine supplementation imparts positive changes within the body including enhancements in lean tissue mass and body composition.
With all this data supporting creatine's value, shouldn't we all just rush to GNC and start sprinkling it on top of all our meals? Not necessarily. Like most supplements, lack of knowledge, coupled with overuse, and/or combining this supplement with other ergogenic aids can together be potentially dangerous. Some researchers fear that creatine can cause renal stress, liver damage, muscle cramping, and hypertension. While no scientifically valid studies have yet supported these claims, studies have shown that creatine causes mild increases in some biological markers in the kidneys and liver (Kreider, et al). Indeed, additional studies are needed to determine the long-term effects of creatine.
If you do decide to add creatine to your dietary regimen, you need to pay special attention to your training, nutrition, fluid intake and lifestyle choices. General loading guidelines are to consume two to five grams (depending on lean muscle mass) four times a day for five to seven days. Maintenance dosing is two to five grams, consumed before and after workouts, for two to four weeks. One should consume 12 to 20 ounces of a high-glycemic drink with powdered forms of creatine, to ensure rapid absorption. Athletes can take one week to many months off, depending on their goals.
Numerous studies have also been conducted in the areas of micro- and macronutrients timing to determine which strategies best produce an anabolic environment. In order to enhance protein synthesis and regenerate glycogen, studies support the consumption of whey protein, high-glycemic carbohydrates, and creatine during the post workout "glycemic window" (less than one hour after a workout). Additionally, athletes can cycle their creatine usage to coincide with power and mass-building training programs.
When considering any supplements, athletes striving to gain an edge on the playing field or in the gym need to consider the building blocks of their program: solid nutrition; a periodized training program involving power, strength, and flexibility; adequate rest; and a clean lifestyle. Creatine may have utility with some power and strength athletes, but knowledge is key prior to starting any supplement plan, and always speak with your doctor first before taking any supplement.
Eric Mink is a former professional football player and the founder of a sports performance clinic specializing in physical training, joint rehab, and nutrition for athletes. Mink has written analytical reports on the pharmaceuticals and nutritional supplement industries, as well as a range of articles in the areas of sports training and rehab, nutrition, and training theory and practice.