The International Society of Exercise and Immunology (ISEI) issued a position statement last year on exercise and immune function. The ISEI differentiates between exercise and physical activity, noting that exercise is goal-oriented, such as to compete in sports or to improve the physical condition, and therefore has greater impact on the immune system than mere physical activity.
The ISEI statement explains how exercise impacts cellular function and inflammation, which can directly affect patients with rheumatic diseases and autoimmune conditions, in negative and positive ways:
- Exercise can suppress the immune system, which increases susceptibility to infection
- During and immediately after exercise, the number of T-cells and B-cells decrease to levels below the preexercise period and return to normal levels within 24 hours; cell activity differs in athletic and sedentary people, with that activity being more sensitive the more athletic a person is
- Exercise can alter the measures of immunity by as much as 15% to 25%
- Exercise confers anti-inflammatory effects, including an increase in interleukin (IL)-1 and IL-10 levels.
ISEI position statement, 2012