The clinical features of inflammatory myositis are determined by the severity and extent of muscle weakness and systemic manifestations. The benefits and limitations of physical training programs and rehabilitation strategies depend on the clinical phase of the disease and analysis of underlying impairments responsible for functional limitations in the patient. Patients with early stage disease and severe weakness will be treated differently than patients who have responded to medication and are improving. Not all patients will respond to medications; their therapy programs will have different requirements. This article reviews available data on the physiologic responses to exercise in patients with inflammatory muscle diseases. New data support more aggressive approaches to progressive strengthening exercises for patients with inflammatory myositis.