Acne mechanica refers to breakouts resulting from excessive sweat, heat, friction, and pressure on the skin. This type of acne differs from acne caused by hormonal changes or genetics. Instead, it's formed by external or 'mechanical' means such as sports bras, fitted shorts, or a face mask. Fortunately, you can prevent acne mechanica by minimizing skin friction. You can do this by (1) avoiding tight skin coverings, (2) washing your hands often, (3) keeping your hands off your face, and (4) wearing loose clothing. Additionally, a gentle, fragrance-free cleanser is also recommended to keep the skin clean and free of excess oil and skin cell buildup.