Effects of caffeine on productivity and mental fatigue
February 6th, 2008
A new study from the Journal of Nutrition shows that caffeine has a positive effect on productivity. The study involved testing the efficacy of two antifatigue substances, caffeine and d-ribose.
Seventeen healthy volunteers were randomised to oral caffeine (200 mg/d), D-ribose (2000 mg/d), or placebo for 8 d.
The candidates were subjected to fatigue-inducing mental tasks: subjects performed a 30-min Uchida-Kraepelin psychodiagnostic test and a 30-min advanced trail-making test on four occasions.
During the tasks, the caffeine supplemented group was better than that of the placebo group. However, post-task fatigue was somewhat different. Though the perceived “…fatigue, motivation, or sleepiness was not significantly different…”, the actual amount of “…plasma branched-chain amino acid levels in the caffeine group were lower than those of the placebo group. Administration of D-ribose had no effect.”
When we get tired due to mental fatigue, plasma branched-chain amino acid (amino acid is protein in its lowest form, e.g. carbohydrate in its lowest form is glucose, fructose etc.) levels decrease.
The results show that the administration of caffeine improved task performance through the enhancement of central nervous system activity without increasing the sensation of fatigue. “However, further decreases in branched-chain amino acid levels indicate that caffeine might promote deeper fatigue than placebo.”
“In contrast, long-term fatigue is sometimes irreversible, and the compensation mechanisms that are useful in reducing acute fatigue are no longer effective. In this view, administration of caffeine might introduce unfavourable situations.”
- Internal tags:branched chain, caffeine, central nervous system, fatigue, journal of nutrition
- Technorati Tags:branched chain, caffeine, central nervous system, fatigue, journal of nutrition
