An oily face after sweating is usually a normal reaction to sebum production.
People usually in hot environments, strenuous exercise, heavy physical labor after the sweat glands lead to a large amount of secretion of sweat to regulate body temperature. When sweat is secreted in large quantities, the sebaceous glands can also increase the secretion of oil, so the face will look very oily after sweating, which is a normal physiological reaction.
If you sweat a lot, you should pay attention to timely washing, keep the skin clean and dry, so as not to cause skin irritation. The excessive secretion of oil on the face can lead to blockage or irritation at the opening of the hair follicle, and then cause acne, inflammatory pimples, etc. Be careful to clean the skin.
Care should be taken to clean the skin in time after sweating to prevent odor, or irritation of the skin to produce dermatitis and so on.