Creatine is a substance found naturally in our bodies that helps provide energy to muscles. Creatine levels refer to the amount of this substance present in our body. Full definition
Comparison of new forms of creatine in raising plasma creatine levels. (rawbarrel.com)
The reason for this is most likely due to these people having naturally high creatine levels (and / or possibly a diet high in red meat). (acaloriecounter.com)
In fact, a good creatine level will help your body gain extra focus that will last throughout the day. (pronutrics.co)