Effects of changes in arousal level by continuous light stimulus on contingent negative variation (CNV).

The purpose of the present study was to investigate an inverted-U relationship between contingent negative variation (CNV) and arousal level which was influenced by extraneous environment. As an extraneous stimulant, stimulation by light was adopted, and five levels of luminance conditions, 10 cd/m2, 100 cd/m2, 320 cd/ m2, 1,000 cd/m2, and 1,800 cd/m2 were provided randomly. Under five luminance conditions, seven subjects who had been accustomed a measurement of CNV executed simple reaction time tasks to evoke CNV.

The effects of preceded fatiguing on the relations between monopolar surface electromyogram and fatigue sensation.

Relations between surface electromyogram (EMG) and fatigue sensation was compared between the first fatiguing contraction and the following contractions with insufficient rests. Six male subjects performed static contractions of the elbow flexors at 8 and 13% MVC with the forearm semipronated and at 13% MVC with the forearm supinated. Contractions were repeated 6 (13% MVC) or (8% MVC) times (C1, C2, C3, C4, C5, C6) with rests of 5 min (13% MVC) or 10 min (8% MVC).

Difference in changes of surface EMG during low-level static contraction between monopolar and bipolar lead.

The changes in surface electromyogram(EMG) during sustained contractions were compared between monopolar and bipolar lead. Ten subjects performed static elbow flexion at contraction levels of 10 and 40% of maximum voluntary contraction(MVC). Seven subjects performed static knee extension at contraction levels of 3, 8, and 15%MVC.

The relationships between lumbar curves, pelvic tilt and joint mobilities in different sitting postures in young adult males.

The lumbar lordosis and pelvic tilt of twenty male subjects were measured in standing and in three different sitting postures with the trunk-thigh angles of 120 (sitting A), 90 (sitting B), and 60 (sitting C) degs and the knee angle was constant at 90 deg. Ten more male subjects participated in the supplemental study, in which additional condition of the knee angle was employed in postures of the trunk-thigh angles of 90 and 60 degs. Some joint mobilities were also measured to investigate the relations of the mobilities to lumbar lordosis and pelvic tilt.

Effects of the direction and distance of horizontal arm movements on local muscular strain--a fundamental study on the teller workplace in bank.

This study was conducted to examine the relative differences in the muscular strain of the hand-arm-shoulder system in the repetitive arm movements which would directly depend on the layout of devices at teller counter. The subjects were five young male adults. The manual handling task was standardized and the repetition frequency was in self-pace.

Changes in relations between surface electromyogram and fatigue level by repeating fatiguing static contractions.

Changes in relations between surface electromyogram (EMG) and fatigue level estimated by fatigue sensation were studied during repeated fatiguing static contractions. Six male subjects performed elbow flexion of 13-15%MVC. Contractions were repeated 5 times (C1, C2, C3, C4, C5) with 5 min intervals of rests.

Effects of contraction level on the changes of surface electromyogram during fatiguing static contractions.

Changes of the surface electromyogram (EMG) during a fatiguing static contraction were studied at contraction levels of 5, 10, 15, 20, 30, 40, and 50% of the maximum voluntary contraction (MVC). Seven subjects performed the static contractions of the elbow flexion and 6 subjects performed those of the planter flexion. Bipolar surface EMG was led from biceps brachii (BB) in the elbow flexion and from soleus in the planter flexion.

The effect of color temperature of lighting sources on the autonomic nervous functions.

The present study was designed to investigate the effects of color temperature of lighting sources on the heart rate variability. Eight male students volunteered as subjects. The heart rate variability during task and rest sessions were estimated under nine different lighting environments consisting of three levels of color temperature (3000 degrees K, 5000 degrees K and 6700 degrees K) and three levels of illuminance (1001x, 3001x and 9001x).

Breathing pattern and subjective responses to small inspiratory resistance during submaximal exercise.

Breathing patterns and subjective responses to small resistances were investigated in seven subjects during moderate exercise. Inspiratory resistances of 0.15 (R1), 0.

Physiological responses to illuminance and color temperature of lighting.

The present study was designed to examine the effects of illuminance and color temperature of room lighting. Four male students volunteered as subjects. Each of them performed a calculation task for 95 minutes under nine different lighting environments consisting of a combination of three levels of illuminance (320lx, 1000lx and 2000lx) and three levels of color temperature (3000 degrees K, 5000 degrees K and 7500 degrees K).