As a result of the coronavirus disease pandemic, it is anticipated that the resulting decrease in the level of physical activity will increase the risk of falls among the frail population. Hence, it is useful to measure the changes in physical activity levels since the onset of the pandemic in this population. This study used information communication technology to obtain the daily step counts of 2248 adults aged 40-89 years between December 2019 and May 2020 to investigate their levels of physical activity. During the pandemic, when outdoor visits were restricted, step counts decreased by 3.5% and 3.7% among males aged 70-79 years and 80-89 years, respectively; and by 0.1% and 8.2% among females aged 70-79 years and 80-89 years, respectively. The frequency of outdoor visits decreased by 16.3% (4.0 days) and 17.8% (4.3 days) in males and females, respectively, in the 80-89-years. In the 70-79-years, the frequency of outdoor visits decreased by 7.1% (1.9 days) and 8.4% (2.3 days) in males and females, respectively. Restriction of outdoor visits due to the pandemic may have a detrimental effect on the amount of physical activity performed by middle-aged and older adult populations.

In this study, we examined the effects of a portable functional electrical stimulator on the knee joint during the early to mid-stance phase of the gait cycle. The electrical stimulation produced eccentric contraction of the quadriceps muscle, which contributes to shock absorption at the knee joint, and reduced the load on the knee joint due to motion modification. Four phenomena occurred simultaneously: an increase in the knee joint flexion angle, an increase in the eccentric contraction of the quadriceps muscle, and a decrease in the vertical and posterior components of the floor reaction force. This was assisted by the eccentric contraction of the quadriceps muscle, which assisted in knee joint flexion and achieved the generation of a double knee action favorable to the shock absorption of the knee joint in the sagittal plane.

Currently, percutaneous energy transmission systems are clinically used for blood pumps, but they have problems such as percutaneous infection as well as transmission power efficiency. In this study, we developed a novel pulsation mechanism for a displacement transmission system using a rotating magnetic coupling component to generate pulsating flow in an implantable blood pump. The pump consists of two magnet plates, a) a semicircular magnetized neodymium magnet plate with a diameter of 80 mm and b) a similarly magnetized neodymium magnet plate with a diameter of 80 mm, coupled to a pump with a passive diaphragm made of polyurethane. A rotating magnetic field was applied to attract or repel the diaphragm supported in the housing of the pump. Hemodynamic performance tests were performed using a mechanical circulatory system; the change in energy consumption under beating conditions of 60?100 bpm was investigated. The results showed that the magnet-coupled pump mechanism was able to generate a pulsatile flow rate of 4.6 L/min at 60 bpm against an afterload of 100 mmHg, indicating effective pumping power even under low pumping speed conditions. The indirect pulsation pump with percutaneous magnet coupling can support systemic blood circulation.