Flu season may last between October and May, but that doesn’t mean you should stop working out for a majority of the year! Dedicated gym-goers often struggle with their conscience urging them to work out daily, even if their body is feeling weak from an illness or disease. Most general physicians will encourage patients to rest until feeling 100%. However, they often neglect the fact that exercise plays an important role in boosting the immune system.
Our body comes into contact with billions of germs every day. Thankfully, our immune system response is extremely effective at fighting off these “invaders” through many levels of barriers including physical (mucus-linings) and chemical (stomach acid), as well as protective white blood cells. In addition to this innate immune system, our body also has an acquired, or developed, backup response which involves the production and releasing of T and B cells from leukocytes (white blood cells).
Exercise normally induces a stress response in the body – one small enough that is easily overcome by a healthy and functional immune system. When a person is sick, their immune system is weakened, however, still partially functional. That being said, there is no reason to stop all forms of physical activity once you feel a cough coming on. Low to moderate intensity workouts will actually leave your body feeling more energized because it triggers a small enough stress response that can be overcome even when the immune system is in a weakened state. For example, a brisk walk through the neighborhood is not going to do any harm, even though a grueling interval workout could send your immune system to an even worse state. Of course, the recommended type and intensity of the workout will vary between people and illnesses, but ultimately, normal exercise while sick is not a danger to your health.
Andrews, Ryan. “Exercise When Sick: Should You Sweat It out? Or Rest and Recover?” Precision Nutrition, 18 June 2015.