Creatine is a molecule that can be naturally produced. However it's widely recognized through
the synthetic form as a sports supplement. In fact, it is one of the most well researched sports
supplements, with over a thousand human studies conducted. The benefits associated with creatine
supplementation's have been well researched, with a consensus in findings such as, increased strength,
increased muscle mass, improved performance and fatigue resistance. Creatine can be acquired in
two ways. The first way is through the synthesis of creatine in our kidneys and liver from amino acids
glycine, arginine, methionine. In the second way is through our diet, mostly through the consumption of
animal products. However it doesn't provide nearly as much creatine compared to creatine supplements.
While there are many forms of creatine supplements the most reliable and well
researched form is creatine monohydrate. Other forms such as creatine HCl and creatine ethyl ester are
not as a well-researched and are unnecessarily more expensive. So now that we know how we get
creatine where does it go in our body? Well about 95 percent of creatine in your body will be stored
in the skeletal muscles. Skeletal muscles are muscles used when performing physical activities
or voluntary movement. Creatine itself doesn't provide much function to our skeletal muscles,
however, when it's converted to phosphocreatine by creatine kinase, an enzyme that can convert creatine
to phosphocreatine and vice-versa. It serves as a small energy reservoir in the form of
adenosine triphosphate, otherwise known as ATP. For skeletal muscles during high-intensity exercise.
Now before further explaining the mechanism of phosphocreatine we need to talk about ATP
first. ATP is made in a mitochondria and is a molecule that provides energy to ourselves.
When ATP is broken down into adenosine diphosphate, otherwise known as ADP the energy released is used
by ourselves. When we perform high intensity exercises such as a squad, benchpress and
sprint, the contracting muscles involved in those exercises require immediate energy,
in the form of ATP. Unfortunately the ATP from my mitochondria isn't able to diffuse rapidly
enough and efficiently enough into the contracting muscle cells. This is when the phosphocreatine
shuttle system comes into play. What happens is the ATP produced in a mitochondria encounters
mitochondrial creatine kinase. This is the same enzyme that converted creatine to phosphocreatine.
The mitochondrial creatine kinase transfers the high-energy phosphate from the ATP to convert
creatine to phosphocreatine producing ADP in the process. The reason why the high energy phosphate
from ATP is transferred over to a phosphoprotein is because phosphocreatine can more easily
diffuse across the mitochondrial membrane to the cytoplasm during exercise there's a lot of
ATP in ourselves so once phosphocreatine is in the cytoplasm we will encounter creatine
kinase that will convert phosphocreatine back to creatine and also transfer that
high energy phosphate to ADP to create ATP. The ATP will then be used by the contracting muscle
cells while the creatine will then return to the mitochondria and this process is then repeated.
So how does creatine supplementation impact this process? Through ingesting creatine we increase
the total amount of creatine in ourselves as a result there will be more creatine in ourselves
that will be converted into phosphocreatine. The increased resynthesis of phosphocreatine is
useful for providing our contracting muscles with an extra boost from energy during high intensity
exercises, thus facilitating the aforementioned benefits. Overall, creatine supplementation is
important for providing extra phosphocreatine to assist in the phosphocreatine shuttle system.
While there's strong support that creatine is safe and poses minimal risks to one's health,
there are numerous health concerns regarding creative supplementation such as dehydration,
digestive problems, also cramps and kidney damage. It is important to stress that the effects of
creatine is variable across individuals that research on its safety and efficacy is quite
limited. In regards to the greatest health concern of kidney damage, a 2019 systematic
review and meta-analysis analyzing the effects of creatine supplementation on renal function thought
that supplementation did not induce kidney damage. However individuals with chronic kidney disease
should avoid using creatine supplementation. Now that you hopefully understand how creatine works
it's important to follow the recommended dosages and if you're still worried about
potential risks I encourage you to conduct your own research to make an informed decision