Mitochondrial myopathy is a type of muscle disease caused by dysfunction in the mitochondria, the energy-producing structures within cells. This condition leads to muscle weakness, fatigue, and exercise intolerance, as the muscles do not receive enough energy to function properly. Symptoms can vary widely among individuals and may include muscle pain and cramps. The condition is often inherited and can be associated with other mitochondrial disorders. Diagnosis typically involves genetic testing, muscle biopsies, and other assessments to evaluate muscle function. While there is no cure, management strategies may include physical therapy and medications to help improve symptoms and quality of life.