Although exercise and overuse of the muscles often causes soreness, other infections and disorders can also cause soreness, states MedlinePlus. Some other causes of muscle soreness include influenza, lupus or fibromyalgia. Nevertheless, tension, stress, overuse and minor injuries are the most common cause of muscle pain, according to Mayo Clinic.
The buildup of lactic acid in the muscles after vigorous exercise causes muscle soreness, explains MedicineNet. The lactic acid that accumulates in the muscles and causes soreness is a natural product of muscle metabolism. However, swelling in the muscle is also responsible for soreness. After a tough workout, white blood cells rush to the site of the muscle to repair it and this action also causes soreness.
When soreness is felt throughout the body instead of in one localized spot, an infection, illness or a medication is usually responsible, states Mayo Clinic. For example, lupus causes soreness because it affects the connective tissues throughout the body, explains MedlinePlus. Fibromyalgia is responsible for muscle pain as it creates tenderness in the muscles and surrounding tissue. Other infections and conditions that cause muscle soreness include Lyme disease, malaria, electrolyte imbalances and polymyositis.
Although these conditions often require the treatment of a doctor, muscle soreness from exercise can often be treated at home, states MedlinePlus. Home treatment often includes rest, anti-inflammatory medications such as ibuprofen and acetaminophen, ice for the first 24 to 72 hours, and massage.