Recently, a standing desk is being installed as a behavior change strategy to reduce sitting time in the workplace. However, the standing posture has been suggested to decrease forehead oxygenated hemoglobin (oxy-Hb), which might impair task performances. Therefore, we examined whether prolonged standing impairs speed and accuracy of computer subtraction task associated with a decrease in forehead oxy-Hb. Nine healthy young males completed 4 × 15-min computer tasks under two conditions, i.e., sitting and standing. In the computer tasks, all subjects were required to subtract a two-digit number from a four digit number written on the paper and to input the answer to the answer colomn on the computer. Task performances were evaluated as the number of achievements and accuracy rate every 15 minutes. Moreover, oxy-Hb and deoxygenated-hemoglobin (deoxy-Hb) in the site of left forehead area and lower limb were monitored throughout the experimental period by near-infrared spectroscopy. Forehead oxy-Hb was significantly associated with the number of achievements during computer tasks (p < 0.001). In addition, forehead oxy-Hb and task performances did not differ between sitting and standing. The number of achievements of subtraction task under standing condition was significantly decreased as time proceeds. Our results demonstrate that prolonged standing might impair computer subtraction task performances irrespective of the change in forehead oxy-Hb.

This study aimed to elucidate the effects of long-term high-fat diet (HFD) consumption and cage restriction-induced physical inactivity (IN) during youth on skeletal muscle autophagy in rats. Three-week-old male Wistar rats were randomly assigned to two dietary groups: the normal diet (ND) and HFD groups. Each group was further subdivided into control (CON) and IN conditions, resulting in four experimental groups (n = 7-8). The HFD group was provided with a diet containing approximately 60% of total calories from crude fat for 16 weeks, from 4 to 20 weeks of age. The ND group received a standard diet for the same duration. The physical inactivity intervention during youth involved restricting the rats’ range of activity by housing them in smaller cages for eight weeks. After 12 weeks of age, the behavioral restrictions were lifted, and all groups of rats were housed in normal-sized cages for eight weeks. The ‘diet group’ and ‘condition’ factors exerted significant effects on the relative muscle weight of the gastrocnemius muscle. The HFD groups exhibited a notable decline in relative muscle weight compared to their ND counterparts. While no significant alterations were observed in LC3-II or p62 expression levels, the ‘diet group’ factor significantly influenced LC3-II/I levels in the white gastrocnemius muscle. These levels were markedly reduced in the HFD group. Our findings suggest that 16 weeks of HFD consumption leads to a reduction in autophagy flux, specifically within the white portion of the gastrocnemius muscle, but this effect is not influenced by cage restriction-induced physical inactivity during youth.