Fatigue in systemic lupus erythematosus: an association with reduced physical fitness.

Systemic lupus erythematosus (SLE) is an autoimmune disease that is characterized by fatigue; however, little research has been performed to identify non-pharmacological strategies, such as physical exercise, that can be employed in the prevention and treatment of fatigue in patients with SLE. Moreover, it is not clear whether physical fitness (defined here as cardiovascular fitness and muscle strength) and functional capacities are related to SLE-associated fatigue. Here, we review the studies, mechanisms and results that relate to SLE-associated fatigue. The main findings indicate that SLE patients have lower cardiovascular capacity than healthy subjects. Physical fitness, muscle strength and functional capacity are also lower in patients with SLE than in healthy individuals. The effects of exercise programs in reducing symptoms of fatigue in SLE patients remain unclear.