The purpose of this study was to measure and analyze peroneus longus reaction time (PRT) as well as ankle movement during ankle sprain simulation. PRT was measured for six control ankles and six unstable ankles with an inversion ankle sprain (1 male and 5 females per group, respectively) using an ankle inverting platform and high speed camera. The unstable group showed a significantly slower PRT (58.8±8.7 ms) than the control group (46.5±8.1 ms). The inversion angular velocity was significantly faster in the unstable group (152.8±62.6 d/s) than the control group (83.2±38.4 d/s). There was no significant difference between the two groups regarding ankle eversion time. Our results indicate that it is important to lead an unstable ankle to reduce inversion angular velocity to prevent recurrent inversion ankle sprain.

Novel coronavirus disease (COVID-19) spread worldwide. In Japan, From April 16 to May 25, 2020, a state of emergency was declared and people were “strongly requested to refrain from going out unnecessarily and thoroughly reduce contact with others.” As a result, the number of steps of all generations was expected to be lower than usual due to the novel coronavirus disease pandemic. This study investigated the weather walking steps decrease in the collegiate student due to COVID-19. A total of 221 collegiate students used their smartphones to enter the average number of steps taken every month from January to May. The number of steps taken by all students was 4,988±2,345 steps in January, 5182±2,516 steps in February, 5,118±2,291 steps in March, 3,281±1,689 steps in April, and 2,834±1,676 steps in May. A comparison between sex groups showed that the number of steps in April and May was significantly different (p<0.05), which means that the steps of women group was lower than that of men. These results suggest that the number of steps taken by students decreased with the outbreak of the novel coronavirus disease.