"Creatine" by Michael Colgan

Creatine

I get a lot of questions about creatine which makes me realize that most people do not really understand its role in the body. This is not helped by the marketing hype with which it is sold which makes it seem anabolic. It is not.

Creatine phosphate is a chemical in your muscles, made by your body from other sources and is responsible for regenerating your primary energy molecule adenosine triphosphate (ATP). If you are an athlete in good shape and rested, your muscles can store enough ATP for about five seconds of maximum work. Stored ATP is the only fuel that instantly produces energy. Therefore it is the only fuel with which the muscle can make maximum contractions. It’s no accident that football players judge their speed by the 40-yard dash, which takes about five seconds, and not 60 yards or 80 yards.

In a 40-yard dash, or any maximum muscle contraction that takes about five seconds, you use all your stored ATP. Your body then has to switch to a less efficient means of energy production, called the adenosine-triphosphate /creatine phosphate (ATP/CP) shuttle. Creatine phosphate in the muscle donates its phosphate molecule to regenerate ATP. This chemical process takes time. Thus the energy supplied to the muscles is less than the instant energy provided by stored ATP.

The possible contractile force of the muscles is reduced accordingly, by about 10%, and so is performance. Hence, an 80-yard dash would not be representative of a football player’s top speed in a sport where short sprints are paramount, because for the last 30 yards or so he is relying on the reduced energy supply of the ATP-CP shuttle.

After your ATP is all used (in about five seconds of maximum contractions), muscles in good shape have a store of creatine phosphate for about another five to six seconds of near maximum work. That makes 10-11 seconds in total.

It’s no accident that the sprint is set at 100 meters, or about 10 seconds. Ten seconds uses all your ATP and your stored creatine phosphate. After that, your muscles have to start converting glycogen to ATP, a much slower process that reduces muscle force dramatically. Even at 10 seconds, and even if you are Donovan Bailey or Maurice Green, you spend the last half of the 100 meter spring fighting against slowing down, because your body has to rely on the less than maximum energy of the ATP-CP shuttle.

Here is a table of the basic biochemistry of energy:

Stored ATP
1-rep max, 40 meter dash

5 seconds
ATP/Creatine Phosphate shuttle
4-rep max, 100 meter sprint
11 seconds
Glycogen & glucose
Hi-rep, ineffective weight training, 800 meter run

120 seconds
Glycogen/fats/amino acids
Aerobics, marathons, triathlons, ultra-distance running

Up to 30 hours

This ATP/CP cycle is anaerobic and uses no glycogen, glucose or fatty acids. This combined ten to eleven second period is the best for optimum strength training. This does NOT mean that creatine builds muscle. It doesn’t, it is used by the body for energy allowing you to work harder for a little longer allowing for more muscle growth. Once the body starts to use glycogen and glucose as its prime forms of fuel then muscle contraction is only about 70% of maximum.

So the best time to use creatine is when you are doing a Power Cycle or training at maximum to get ready for a competition and are doing major strength work. By using creatine at this time you can increase your lean mass by 2.5 to 3.5 lbs in about 30 days. This increase in strength translates to an increase in power of about 6.5% more than placebo. Any athlete involved in a sport that features quick short bursts of energy such as sprinting, weight-lifting, jumping, or rowing will benefit from using creatine in cycles that correspond to their training regime. So during any weight training time, cycling creatine is a good idea even if your sport is triathlons. But using it during a triathlon is of no benefit at all as your body is going to be running on glycogen, fats and amino acids and not using ATP or the ATP/CP shuttle during an endurance event.

For more information on this topic you can read Dr. Colgan’s small booklet called “Creatine” or attend our Power Program Camp in August on Saltspring Island.

[workitforme]

Saltspring Island in BC canada?

Probably yes...he's Canadian, I think.