By exercising regularly, so your muscles will adapt gradually to the workout. This will lessen the soreness. Delayed-onset muscle soreness usually appears 24 to 48 hours after a workout, causing localised pain, stiffness and swelling, loss of range-of-movement and even loss in strength. It generally lasts up to 96 hours. Make sure you stretch adequately after every workout, and eat a healthy diet with good quality proteins to facilitate muscle growth and repair.