Objective: We conducted a clinical study to investigate the effects of a combination of wooden interior and indirect lighting in the bedroom on improving sleep quality and attenuating fatigue. Design: Eleven healthy male subjects, whose Pittsburgh Sleep Quality Index (PSQI) scores were ≥ 6, participated in a 3-way crossover trial. Subjects rested from 21:00 to 22:00 under a combination of wooden interior and indirect lighting, indirect lighting, or direct lighting, went to bed at 22:00, and awoke at 6:00. We evaluated sleep quality by the St. Mary's Hospital Sleep Questionnaire (SMHSQ), autonomic nervous function by the Active Tracer, sleepiness and fatigue sensation by the Visual Analogue Scale (VAS), and performance by the Advanced Trail Making Test (ATMT). Results: The combination of wooden interior and indirect lighting improved early morning awakening, nocturnal awakening, and satisfaction with sleep according to the SMHSQ, activated the parasympathetic nerve system at bedtime according to the Active Tracer, and attenuated sleepiness and fatigue sensation at the time of awakening according to the VAS; moreover, it improved work performance according to the ATMT. Conclusion: These results show that the combination of wooden interior and indirect lighting produces a suitable bedroom environment that improves sleep quality and attenuates fatigue.

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.

In the present study, in order to investigate the healthy functionality of superheated steam cooking, we examined triacylglyceride, RLP-cholesterol, ascorbic acid and d-ROM levels in blood after intake of fried pork cooked using superheated steam or in a deep fryer. At 6 hours after intake, in the superheated steam cooking group, triacylglyceride and RLP-cholesterol levels were lower, while ascorbic acid levels were higher and d-ROM levels were lower when compared with the deep fryer group. These results suggest that superheated steam cooking has healthy functionality with regard to the inhibition of postprandial triacylglyceride increase and lipid peroxidation in blood.

Objective: Plasma cluster ions consist of positive and negative ions and are known to suppress the activity of total bacteria, mold fungi, viruses and allergens floating in the air. In terms of inactivating mite allergens, it was reported that plasma cluster ions suppressed the symptoms of atopic dermatitis in mice. In the present study we investigated the effect of plasma cluster ions on attenuating chronic allergic rhinitis and fatigue induced by mite allergens in humans.
Design: Sixteen subjects with specific immunoglobulin E (IgE) positive to Dermatophagoides pteronyssinus, who had symptoms of allergic rhinitis caused by house dust participated in a randomized double-blinded crossover trial. Subjects occupied a mite allergen challenge room and performed mental task for 4 hours with 25,000/cm³ plasma cluster ions or without plasma cluster ions and rested for 2 hours outside of the room. We measured mite allergens (Der p1) on the floor using plastic dishes (90 mm diameter) placed at 5 points in the room. We also investigated the symptoms of allergic rhinitis using the Japanese Allergic Rhinitis Standard QOL Questionnaire (JRQLQ) during the 4-hour load and 2-hour rest and performance by Uchida-Kraepelin psychodiagnostic test during the 4-hour load.
Result: Plasma cluster ions inactivated 80–90% of Der p1 and attenuated the symptoms of nasal congestion in JRQLQ. Moreover, plasma cluster ions inhibited fatigue-induced impaired performance in Uchida-Kraepelin psychodiagnostic test compared to the case without the ions.
Conclusion: Plasma cluster ions reduce mite allergens and are effective for attenuating chronic allergic rhinitis and fatigue.

Objective: We conducted a clinical study to investigate the effects of newly developed LED lighting on living comfort in an indoor environment.
Design: Twenty healthy subjects participated in a randomized crossover trial. They performed a mental task for 4 hours under ordinary lighting, and then rested for 1 hour under newly developed lighting or ordinary lighting. Sixteen of the subjects (8 males, 8 females) completed the trial. We evaluated subjective comfort using a visual analogue scale (VAS) and measured autonomic nervous system effects by the frequency analysis of a-a intervals on accelerated plethysmography (APG) waves.
Result: The subjects’ VAS evaluations showed that the newly developed lighting increased their comfort, while frequency analysis of APG during the rest period was found to activate the parasympathetic nerve system.
Conclusion: This newly developed LED lighting produces suitable illumination and color temperature and is useful for improving living comfort in an indoor environment during a rest period after daytime work.

Objective: We conducted a clinical study to investigate the effects of newly developed LED lighting on living comfort and work performance in an indoor environment.
Design: Sixteen healthy subjects participated in a randomized crossover trial. They performed a mental task (2-back task and ATMT) for 8 hours under newly developed LED lighting or ordinary LED lighting. We evaluated subjective comfort using a visual analogue scale (VAS) and work performance by ATMT. Moreover, we measured changes in the autonomic nervous system by frequency analysis of a-a intervals on accelerated plethysmography (APG) waves to elucidate the mechanism of action.
Result: The subjects’ VAS evaluations showed that the newly developed LED lighting increased their comfort and attenuated their fatigue, and ATMT evaluations showed the lighting improved work performance during the mental task period, while APG frequency analysis revealed changes in the parasympathetic nerve system.
Conclusion: This newly developed LED lighting produces suitable illumination and color temperature and is useful for improving living comfort and performance in an indoor work environment.

Objective: In the present study, we investigated the effects of enveloping-airflow air conditioner on health maintenance and fatigue in healthy volunteers. The enveloping airflow is that of gently holding the whole room space along the ceiling, wall, and floor.
Design: In a randomized placebo-controlled crossover trial, 10 healthy women who had feeling cold, stiff shoulder and knee pain very often under air conditioner working, participated in the study. They performed fatigue-inducing desk work for 2 hours, and rested for 30 minutes in the air conditioned room controlled by enveloping airflow or direct airflow.
Methods: We evaluated subjective sensation by Visual Analogue Scale (VAS), peripheral blood flow by laser-Doppler flowmetry, and body temperature.
Result: The enveloping airflow prevented hypothermia, increased blood flow, moreover attenuated feeling of cold, knee pain and fatigue, increased sensation of comfort as compared with the direct air flow.
Conclusion: Enveloping-airflow air conditioner is effective in maintaining health and attenuating fatigue.

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.

Objective Enveloping airflow, as opposed to direct airflow, warms the room by gently circulating the airflow along the floor, wall, and ceiling, thereby uniformly warming the entire room. The objective of our study was to determine the effects of air-conditioned heating by enveloping-airflow on sense of fatigue and comfort in healthy volunteers.
Design Eight healthy women, who often felt discomfort in an air-conditioned heating environment, participated in a randomized placebo-controlled crossover trial. Subjects rested for 30 minutes in a room air-conditioned either by enveloping airflow or by direct airflow, and then performed fatigue-inducing tasks for 2 hours.
Methods We evaluated the sense of fatigue by visual analogue scale (VAS), peripheral blood flow by laser-Doppler flowmetry, and sympathetic nerve activity by urinary vanillylmandelic acid level.
Result Air conditioning by enveloping-airflow, as compared to direct airflow, enhanced peripheral blood flow and attenuated sympathetic nerve hyperactivity caused by performing fatigue-inducing tasks. Moreover, it helped to maintain subjective levels of motivation and comfort, as well as to alleviate sense of fatigue and cold.
Conclusion Air-conditioned heating by enveloping-airflow is effective for attenuating sense of fatigue and discomfort as well as health maintenance.

In the present study, we investigated the effects of plasma cluster ions on moisturizing skin and increasing comfort sensation in healthy female volunteers. Thirty-two healthy women who often experienced dry skin participated in a randomized crossover trial. We evaluated skin moisture using the Corneometer CM825 and comfort sensation using the visual analogue scale. Plasma cluster ion concentrations of 25000 pcs/cm³ increased skin moisture, while concentrations of 7000 pcs/cm³ increased comfort sensation. These results suggest that plasma cluster ions have an effect on skin moisture contents and comfort sensation.