Our study involved 12 adult females. In the first series, we compared clothing conditions O and C, both of which have a clo value of 1.00 clo at 21.2°C. The clo values of clothes at the lower extremities were 0.27 and 0.45 under conditions O and C, respectively. In the second series, we compared clothing conditions S and L, both of which have a clo value of 0.22 clo at 28.2°C. The clo values of clothes at the lower extremities were 0.06 and 0.10 under conditions S and L, respectively. When comparing the clothing conditions between O and C, no significant difference was found in the whole-body thermal sensation. However, local thermal sensations for the lower legs and feet were considerably higher under clothing condition C than those under clothing condition O. Similarly, when comparing the clothing conditions between S and L, no significant difference was found in the whole-body thermal sensation. However, local thermal sensations for the thighs were substantially higher under clothing condition L than those under clothing condition S. In many instances across both series, a remarkable correlation between the whole-body and local thermal sensations was observed.

This study aimed to determine the effects of mental fatigue on muscle activity and exhaustion during sustained submaximal handgrip contraction at different arm postures. Healthy volunteers performed sustained handgrip contractions at 30% maximum voluntary contraction until exhaustion in the 90° of shoulder flexion position (PROX condition) or neutral position (DIST condition) after a 30-min Stroop task (MF condition) or watching documentary task (control [CON] condition). The time to task failure did not differ significantly among the four conditions. The electromyography values recorded from the anterior deltoid were significantly higher in the MF than CON condition, but only in the PROX condition. This study indicates that mental fatigue does not influence sustained handgrip contraction performance but does increase muscle activity of anterior deltoid with shoulder flexion angles.

Light input through the eye significantly impacts human health and well-being by regulating circadian rhythms, sleep, neuroendocrine, and cognitive functions. Evaluating light is crucial for ensuring an appropriate lighting environment, with photometric units based on illuminance currently being the norm. However, illuminance, a unit based on visual light sensitivity, does not adequately assess non-visual effects such as circadian rhythm phase shifts and melatonin secretion suppression. This paper outlines the background to the establishment of melanopic equivalent daylight illuminance (EDI), a new international standard for quantitatively evaluating the non-visual effects of light, and indoor lighting recommendations based on this standard.