Muscle mass and heatstroke Muscle mass and heatstroke
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Muscle mass and heatstroke

    NHK World
    Correspondent
    As Japan battles through record heat this summer, one medical expert says it should be viewed as seriously as a natural disaster, and warns that the COVID-19 pandemic is leaving people even more vulnerable to heatstroke due to lifestyle changes that have left them with weakened muscles.

    Muscles store fluid

    Hattori Masuji, a guest professor at Hyogo College of Medicine

    Heatstroke expert Hattori Masuji, a guest professor at Hyogo College of Medicine, says muscles play an important role in temperature regulation. They retain fluid that is used to cool the body during hot weather.

    Less muscle means less fluid, and that can increase the risk of dehydration. Hattori says many people have lost muscle mass due to lack of exercise during the COVID-19 pandemic.

    Precautions for heat

    Hattori says it is important for people to build and retain muscle, particularly the large muscle groups in the lower part of the body, but that takes time. In the meantime, he has the following suggestions for avoiding heatstroke:

    Control indoor temperature and humidity

    Use air conditioners and other aids to set an indoor temperature of about 26-27 degrees, and humidity at 60-70 percent. Keep air conditioners turned on overnight.

    Frequent water intake

    Masks can make people less likely to recognize thirst, so drink some water at least once an hour. At a minimum, consume 100-200ml every 1-2 hours.

    Caffeinated beverages and alcoholic drinks can have a diuretic effect. When drinking alcohol, match intake with an equivalent amount of water.

    Exercise

    Exercise can help because as the body temperature rises, blood vessels widen to increase blood flow and release heat. It also builds muscle mass and improves sweating efficiency.

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