All we ever heard the phrase “what does not kill us makes us stronger.” We do not know how much this event will be right, but certainly can be applied to exercise. And that intense training interferes with the balance of the body (homeostasis) and triggers an inflammatory response.
A consequence of this the body becomes stronger so that the same exercise will be less stressful in the future. However, excessive exercise causes a sobreeentrenamiento decreasing the resilience and enllentece progress.
Blood markers that show overtraining puden be auemtno cortisol (stress hormone), TBARS (marker of oxidative damage), interleukin-6 (IL-6, a chemical that helps combat trauma) and neutrophils (blood cells infection-fighting white).
Cortisol is important for the regulation of blood sugar and blood pressure as well as the inflammatory response to illness, stress and injury. High levels of cortisol suppress the immune system, increasing the risk of constipation and flu.
You can also slow the response to training by stimulating muscle and bone degradation and interfere with the metabolism of carbohydrates
British scientists could observe that the supplementation of 1000 mg of vitamin C and 400 IU of vitamin E daily for 4 weeks reduced the levels of cortisol after intense exercise (2 hours cycling at 60% effort) but had no effect other measures of immunity.
Vitamin C and E can reduce some of the negative effects of intense exercise but cannot completely protect against the depression of the immune system. A correct design of the GSE exercise (keeping a balance between intense exercise and enough sleep) and a good diet with adequate energy intake are the best protection against depression of the immune system induced by overtraining and diseases with the profits inbterferirán training.