For those wondering, creatine is a body building supplement that has extraordinary effects on muscle growth and workout performance. It is a controversial supplement as it is commonly misidentified as a steroid.
Creatine is a combination of three amino acids. These acids are glycine, arginine, and methionine. Creatine is an all natural substance created in the body and is found in foods. In other words, creatine is NOT a steroid.
It does enhance workouts but the way it works is very interesting. Per Layne Norton at bodybuilding.com, creatine helps produce more ATP. ATP works the way you stated Eline, by hydrolysis. It hydrolyzes a phosphate group. This means it looses a phosphate group turning Adenosine Triphosphate(ATP) into Adenosine Diphosphate(ADP). The process releases energy which drives the desired process. This is how ATP works.
Now we are left with ADP which is not as useful as ATP as it cannot hydrolyze. This is where creatine really shines. Creatine turns ADP into ATP. It does this by donating its phosphate group to ADP. After donating a phosphate group the ADP is re-formed into ATP to be used again! It seems like magic but it is just science.
Are there downsides? Some people have experienced stomach pains but according to bodybuilding.com, this is usually due to taking it on an empty stomach. In his article Layne Norton states that creatine monohydrate is the most studied form of creatine. He recommends that people stay with creatine monohydrate until more information is available on the other forms.
Does anyone have any thoughts or comments about creatine? I am personally interested and will be ordering some creatine monohydrate to try.
References: https://www.bodybuilding.com/content/creatine-what-it-is-and-how-it-works.html https://www.britannica.com/science/adenosine-triphosphate https://jissn.biomedcentral.com/articles/10.1186/s12970-017-0173-z