Strength athletes use creatine to get more reps out of their sets, and thus speed up their muscle growth. Creatine has a similar effect in your brain, neuro-psychiatrists at the University of Tokyo discovered a decade ago. If you take creatine you can use your brain intensively for a longer period of time.
In 2002 the Japanese published in Neuroscience Research the results of a study in which they used 24 students aged 19 as subjects.
The students got the students to add up a random series of numbers for a period of 15 minutes. The Japanese used the Uchida-Kraepelin test that psychiatrists use to measure mental fatigue. The more numbers you can add up, the fitter you are. In mental terms at least.
At the end of the 15-minute exercise the students rested for five minutes. After that they had to do another 15 minutes of addition.
The researchers carried out the whole procedure twice. On one occasion the students were given 8 g of creatine monohydrate five days before the test, on the other occasion they were given a placebo. The creatine that the Japanese used came from Ezaki Glico.
When the students had taken the creatine they were able to do more addition sums. The scores of a typical student are shown below, with and without creatine.
Using near infrared spectroscopy the researchers were able to study the composition of the blood in the brains of their subjects while they were doing the sums. They looked at the amount of oxygen that was attached to the haemoglobin molecules in the blood. The figure above shows that the blood in the brains of the subjects had more haemoglobin without oxygen [Desoxy-Hb] when the subjects had taken creatine.
The researchers also noticed that the number of haemoglobin molecules with oxygen was fewer when the subjects had taken creatine than when they had taken a placebo. That probably means that creatine supplementation boosts the oxygen consumption of the brain cells. It seems that brain cells work harder if you take creatine, the Japanese suggest.
“Our experiment may suggest a new line of approach to reduction of mental fatigue involving creatine”, the researchers conclude.
Effects of creatine on mental fatigue and cerebral hemoglobin oxygenation.
While the role of creatine in preventing muscle (peripheral) fatigue for high performance athletes is well understood, its biochemical role in prevention of mental (central) fatigue is not. Creatine is abundant in muscles and the brain and after phosphorylation used as an energy source for adenosine triphosphate synthesis. Using double-blind placebo-controlled paradigm, we demonstrated that dietary supplement of creatine (8 g/day for 5 days) reduces mental fatigue when subjects repeatedly perform a simple mathematical calculation. After taking the creatine supplement, task-evoked increase of cerebral oxygenated hemoglobin in the brains of subjects measured by near infrared spectroscopy was significantly reduced, which is compatible with increased oxygen utilization in the brain.
PMID: 11985880 [PubMed – indexed for MEDLINE]