The first question people always ask after they discover the nutritional benefits of a new supplement is, will it work for me? The next question is invariably, how does it work? To answer these questions about the popular new supplement
creatine monohydrate, we'll start with how it's purported to work.
Creatine plays two roles in the body. Its primary function is to act as a reservoir of bound phosphate in the form of adenosine triphosphate, or ATP Its secondary role is to scavenge leftover free phosphate after ATP breakdown, thereby
elevating, or buffering, as it's called, local muscle pH. The more trained the muscle, the more creatine is present to manage acid and act as a reservoir. The body naturally makes its own creatine in response to training, but supplementation
is a valid way to increase performance. To understand why, you'll need a short background on muscle physiology.
How Contractions Are Fueled
Most bodybuilders have heard of ATP and they probably know that it's considered to be the energy currency of all living cells. ATP is called "currency" because like money it can be applied to many different situations. Money can buy all kinds
of goods and services, from erasable-ink pens to Ferraris and from four-course meals to tax preparation. ATP like cash currency, can be exchanged in nearly every conceivable cellular situation, from changing microscopic concentrations to
helping synthesize proteins and from sending molecular messages to physically moving cellular components. That last item is most important for this discussion because creatine participates in moving muscle proteins.
ATP supply is particularly crucial for athletes because its presence is the molecular driving force behind every single muscular contraction-everything from blinking an eyelid to blasting eight-plate squats. To cause that latter forceful motion,
ATP is actually exchanged for changes in the length of muscle proteins in the cells. When you decide to contract a muscle, nerve impulses that deliver your decision cause muscle proteins to accept ATP in exchange for shortening their length
microseconds later. When the lengths of billions and billions of microscopic muscles are shortened at roughly the same time, the overall effect is a leg or bench press, a curl or some other meaningful muscle contraction. Needless to say,
the availability of ATP is solely responsible for this final action. To put it another way, without ATP you wouldn't get very far in life.
The Basics of Acids
For years science has believed that metabolic intermediates were responsible for sensations of fatigue and failure during workouts. Studies performed in the l950's established that lactic acid can cause fatigue and sensations of pain when
injected into a muscle-but so can a lot of other organic acids. These studies were never followed up, and their questionable conclusions remain with us to this day. It simply followed logically that metabolic intermediates such as lactic
acid would naturally accumulate from the large energy demand of rapid anaerobic exercise and eventual ATP depletion, causing fatigue. Well, that does occur, but it occurs much later in the process and is less responsible for immediate fatigue
and failure than the twin evils discussed below, ATP-generated acid and ATP depletion.
The "tri' in the term "adenosine triphosphate" means that there are three phosphates in a chain in the molecule. The reason the ATP is such a great energy currency is because it's pretty stable most of the time. It won't just break down for
no good reason. In fact, it's so stable that it almost always takes an enzyme to break down ATP. The final exchange of ATP for mechanical processes such as muscle contraction is the enzymatic breaking down of the Last phosphate in the chain.
The result is a change in muscle protein length and shape, plus one free phosphate molecule and a molecule of adenosine diphosphate, or ADP, which contains the two remaining phosphates in the chain. It's a seldom-reported fact that when ADP
and free phosphate are created in this manner, acid is also formed. Consequently, when you work out, acid rapidly accumulates as a result of ATP breakdown. It's true. Every time a molecule of ATP is converted, a molecule of acid is formed.
During a single curl performed with a 10-pound dumbbell, literally trillions of ATP molecules are broken as trillions of acid molecules are formed. Now, the effect of this acid isn't even noticed in well-trained individuals, but if that weight
were pumped rapidly in a 100-rep set, even the most well- trained folks would experience muscle failure long before they completed the set. The significance of this point is that the formation of free phosphate from ATP significantly lowers
the pH of the ,muscles-that is, it increases the acid content-and this disrupts the function of the contractile muscle proteins, which leads to what we call failure. Now that you understand where this acid comes from, you can more easily
understand what to do to improve the situation. You must simply find some way to alleviate the excess free phosphate that's generated during a workout.
The good news is that nature has already found a solution-creatine. Creatine is nature's acid mop. Its job is to absorb excess phosphate from inside muscle tissue and so eliminate excess acid and elevate the p!-1 toward neutral. This is called
Not just for ph Management
When creatine with the help of another enzyme picks up free phosphate, the local pH is elevated toward neutral, and the creatine becomes creatine phosphate, or CP. What's more, the phosphate molecule in CP can be transferred back to a molecule
of ADP to reform ATP That's right, when ADP gets a phosphate molecule from CE it re-creates a molecule of ATP This isn't a rare event, In fact, 80 to 85 percent of all functional muscle phosphate is stored, if you will, in the form of CR while
only around 20 percent of muscular energy potential is actually stored as ATP at any given time. If there were no creatine pool, that ATP would disappear very quickly during a workout.
This usable reservoir of high-energy phosphate feeds the muscle's ATP demand during heavy exertion because, as ATP is converted to ADP, many creatine phosphate molecules become available to immediately transfer their phosphate back to ADP to
make more ATP This is what stabilizes the pool of ATP in working muscle. Creatine has along, repetitive life that consists of these phosphate transfer reactions. The larger the pool of creatine, the larger the potential pool of ATP and,
therefore, the longer and more powerful the workout. Supplementing creatine can only enhance your ability to work longer and at a higher intensity than has ever before been possible. Creatine excels at helping athletes who perform anaerobic
activities, like sprinters, shot-putters, powerlifters and bodybuilders, but that doesn't mean that only those people should use it. Every strenuous activity has an associated anaerobic component-a period of acid buildup, ATP depletion and oxygen
So, in effect such endurance performers as aerobics athletes, cyclists and runners can all expect to substantially benefit from creatine use. In fact, creatine synthesis in muscle is a major step in the process of getting in shape. Consumer
Awareness Pharmaceutical creatine is prepared so that each creatine molecule is associated with a single water molecule. That's why it's called creatine monohydrate. Creatine is as stable as any amino acid currently sold on the market, but
like arginine and glutamine it's believed to be unstable in liquid form. There are no existing studies that demonstrate that creatine is toxic; it's believed to be extremely safe.
Creatine phosphate is considered to be an inferior supplement to creatine monohydrate because the phosphate adds unnecessary weight and isn't really required. For example, one gram of creatine monohydrate contains almost 60 percent more creatine
than one gram of creatine phosphate. There are also serious questions about the biochemical necessity of creatine phosphate supplementation, primarily because creatine monohydrate is absorbed so much more efficiently. Research on creatine
supplementation shows that after an initial increase in muscle creatine concentration, the creatine stabilizes at a steady-state concentration. In the studies the amount of daily creatine supplementation was reduced, and there was no decrease
in performance enhancement.
Therefore, while creatine is closely associated with improved athletic performance, you don't want to waste your money by taking too much of a good thing. If you stop taking supplemental creatine, muscle creatine concentrations may remain at the
same levels for a few days, but you should take it daily to assure optimal performance.