According to a 1999 epidemiological survey by the Fatigue Study Group of the Ministry of Health, Labor and Welfare in Japan, 60% (47 million) of workers complained of fatigue. However, there have been no established recommendations for fatigue, and few anti-fatigue medicines or foods have been developed. Physical or mental load induces oxidative stress, resulting in fatigue. Accordingly, antioxidants are candidate anti-fatigue substances. Imidazole dipeptides (carnosine and anserine) have strong anti-oxidative effects, and chicken breast is rich in such dipeptides. The results of two human studies suggested imidazole dipeptides were effective and useful in attenuating fatigue induced by physical loads and daily activity. In short, imidazole dipeptides are novel anti-fatigue ingredients.

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Coix lacryma-jobi L. var.ma-yuen Stapf (coix seed) is a grass crop that has long been used in traditional medicine as a nourishing food. However, high-intake safety of the extract of the husks, pellicles and astringent skin of coix seed has rarely been evaluated. We performed a 28-day repeated dose oral toxicity test of hot water extract of all parts of Coix seed in rats. The extract showed no significant toxicity on body weight, blood analyses, urinalysis and histopathological examination in acute toxicity tests.

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Objective: It has been reported that essential oils used in aromatherapy effect the nervous, immune and endocrine systems. The purpose of this study was to assess the effects of essential oils on the cardiovascular system in healthy human subjects.
Methods: Rosemary essential oil, which reportedly has a vasopressor-like effect, and lavender essential oil which reportedly has a depressor-like effect, were administered to sixty subjects divided into rosemary, lavender, or control groups. Blood pressure and heart rate were measured after two-minutes of smelling. Data were compared among the three groups.
Result: Heart rate increased in the rosemary group. In addition to blood pressure and heart rate increased in subjects who expressed a negative impression from smelling a specific essential oils.
Conclusion: The results suggest that fragrance preference affects the therapeutic effects of aromatherapy.

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Objective According to a survey conducted by the Japanese Ministry of Health, Labor and Welfare in 2002, 72% of workers feel fatigued, clearly indicating the degree to which the Japanese populace is affected by this problem. However, few scientifically proven anti-fatigue devices have been developed for the benefit of the Japanese society. An automated air massage chair provides soft stimulation with air bags, not spot stimulation with knead balls, over the muscle surface with movements that push the muscles upward. In the present study, using established methods to evaluate fatigue, we investigated the effect of this automated air massage chair on fatigue in healthy volunteers.
Method Ten healthy subjects participated in a randomized two-way crossover trial. As fatigue-inducing desk work, subjects performed 8 sets of a 30-min Uchida-Kraepelin psychodiagnostic test and 30-min advanced trail making test (ATMT) during the test day. Subjects rested 15 min on the air massage chair or control chair 4 times: immediately before and at 4, 6 and 8 hours after the start of the workload. We evaluated the subjective feeling of fatigue by visual analogue scale, work performance by ATMT, and analyzed underlying mechanisms by biochemical parameters in saliva and urine.
Result Stimulation by air massage chair alleviated the subjective sensation of fatigue and suppressed the decline in work performance. Furthermore, increase in salivary amylase activity and decrease in urine homovanillic acid/creatinine ratio was suppressed.
Conclusion Automated air massage chair attenuated fatigue induced by desk work, most likely by correcting the imbalance in the autonomic nervous system. The air massage chair is thus recommended for relieving fatigue induced by work and daily activities.

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Objective: The effects of essential oils on the formation of superoxide radicals during UVA (365 nm) irradiation were investigated.
Methods: ESR (electron spin resonance) spin-trapping experiments were performed on a reaction mixture containing 15 μM riboflavin, 0.10 M DMPO (5,5-dimethyl-l-pyrroline-N-oxide), 23 mM phosphate buffer (pH 7.4) and 6.3% (v/v) DMSO (dimethyl sulfoxide) (standard reaction mixture) during UVA (365 nm) irradiation.
Results: On addition of various concentrations of tea tree oil (or lavender super oil or grapefruit oil or peppermint oil or wintergreen oil) to the standard reaction mixture, the ESR peak height decreased dose-dependently.
Conclusion: This result shows that antioxidant activities increase as follows: lavender super oil<grapefruit oil<peppermint oil<tea tree oil<wintergreen oil.

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Coix lacryma-jobi L. var. ma-yuen Stapf is a grass long been used in traditional medicine as a nourishing food and reported to possess pharmacological effects including anti-tumor, anti-obesity, anti-diabetic, etc. In order to evaluate the possible mutagenicity of the hot water extract of all parts (husks, pellicles, and astringent skin) of the food, we performed a reverse mutation test in bacteria, a mouse lymphoma assay and a mouse micronucleus test. The results of all tests were negative. It was concluded that the extract has no mutagenicity for living bodies.

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