Moderate exercise can actually have a beneficial, boosting effect on our immune health. On the other hand, intense & exhaustive exercise can contribute not only to inflammation and oxidative stress, but also immune dysfunction. Athletes who are adequately fed, and well-rested (both critical to stave off over-training syndrome), typically can handle the stress from exercise. Those who under-eat and fail to consume adequate carbohydrates and protein after exercise, as is the case with dieters and those who are ‘too busy’ to eat, are at greater risk of compromising their immune system. The best nutritional advice to counter this is as you plan time for training, also plan for adequate fueling. After all, you can’t out-train a poor diet.
Exercise’s Role in Immunity, the Yin and the Yang