Objective: To determine the association between changes in low back pain and in presenteeism in workers before and after the epidemic of the new coronavirus (COVID-19), and to further examine the association by assessing changes in working patterns.

Methods: A cross-sectional analysis was conducted on 1865 workers (mean age 49.6±6.6 years) who participated in an online survey. We investigated changes in low back pain and presenteeism associated with the COVID-19 epidemic and examined the relationship between worsening low back pain and presenteeism.

Results: Worsening of low back pain was significantly associated with the occurrence of presenteeism in the group without pre-epidemic presenteeism (odds ratio: 4.26, p<0.01) and worsening of presenteeism in the group with pre-epidemic presenteeism (odds ratio: 1.80, p=0.01).

Conclusion: The worsening of low back pain following the COVID-19 epidemic was associated with presenteeism, and this association was particularly strong in a group of people who were continuously engaged in office work.

Objective: This study aimed to compare the effects of acute Electrical Muscle Stimulation (EMS) on arterial stiffness when applied to different parts of lower limbs.

Methods: Fifteen healthy young men were included in three trials in a randomized order. Participants rested in the supine position for 20 min with EMS applied to either the whole of both lower legs (L), both thigh muscles (T), or both calf muscles (C). The brachial-ankle Pulse Wave Velocity (baPWV) and brachial systolic/diastolic blood pressure were obtained before and after each trial.

Results: The baseline hemodynamic values were not markedly different between the three trials. Compared with baseline values, baPWV was significantly decreased after all trials (p<0.05). The baPWV after trial L was significantly slower than that after both C and T trials (p<0.05).

Conclusion: These results indicate that EMS applied to the whole lower limb improves the arterial function more markedly than EMS applied to the calf or thigh muscle alone.