Immune System Weak in Morning—Avoid Exercise
Many people have the habit of exercising early in the morning, believing fresh air is beneficial for health. However, according to a medical study published in the UK on the 30th, the immune system operates at its weakest during early morning hours, so morning exercise may actually increase the risk of catching illnesses.
According to research from the University of Brunel in the UK, the concentration of “cortisol,” a substance that suppresses immune function, is higher in the morning than at other times of day. Meanwhile, levels of IgA, a marker of immune system activity, are relatively low.
Therefore, experts recommend that the optimal time for exercise is not in the morning but in the evening, to reduce the risk of infection.