We know that long-distance running brings a lot of dangerous changes – it can induce bleeding (blood may appear in the urine and protein in the urine), breakdown of red blood cells and muscles, hormonal disorders (decrease in the amount of testosterone, hemoglobin and hematocrit). It is also possible that muscle breakdown will lead to serious kidney damage.
In the study of Kenneth Ostrowski et al., The extent and duration of prolonged exercise affects blood levels of proinflammatory and cytokine reactants as well as cytokine and anti-inflammatory cytokine inhibitors.
10 men (average age 27.5 years) graduated from the Copenhagen Marathon in 1997 (at an average time of 3 hours and 26 minutes). Blood samples were collected before, immediately after and then every 30 minutes in 4 hours during the regeneration period after exercise.
Comment and how to understand it
Interleukin 6 (IL-6) has pro- and anti-inflammatory activity. Currently, it is known that its main role is participation in the immune response and inflammatory response and in the formation of blood. Neoplasms secrete large amounts of IL-6, which are fundamental for the growth of pathologically changed tissues and metastasis (including angiogenesis, proliferation, attachment and invasion). If IL-6 is caused by muscle activity, it contributes to the synthesis of other anti-inflammatory cytokines, such as IL-1ra and IL-10, while inhibiting proinflammatory cytokines such as IL-1β and TNF-α (tumor necrosis factor). Unfortunately, IL-6 also stimulates the production of CRP acute phase protein in the liver, which was stated in 2002 by Ridker et al. In turn, CRP is responsible for cardiovascular events, for example. However, regular training associated with the reduction of fat reduces the amount of CRP in the runner’s body. In yet other studies, IL-6 changed the amount of arrhythmia in runners.
IL-1β in the beta variant (importantly), a proinflammatory cytokine, plays a major role in rheumatoid arthritis, for example. It can affect the production of CRP.
TNF-α (tumor necrosis factor) corresponds to, e.g. for neovascularization of tumor or angiogenesis (formation of new vessels supplying the tumor). Paradoxically, it can be highly harmful to the heart by inducing apoptosis. Despite its name, it influences, among others on the increase in mortality. TNF-α is involved in the production of other pro-inflammatory cytokines, such as IL-6, IL-1, which exacerbate the metabolic-related myocardial disorders caused by TNF-α.
Generally it seems that runners should drink beetroot juice. In one Asgara S study from 2016, 24 people with hypertension aged 25-68 years were divided into 2 groups – one saw juice for 2 weeks, the other consumed boiled beets. After 2 weeks and a 2-week break period, the groups were swapped. Each participant drank 250 ml of juice daily or ate 250 g of beet a day for 2 weeks. After 2 weeks, there was a significant decrease in CRP and tumor necrosis factor – alpha (TNF-α), and this means less inflammation in the body in the group that drank juice (greater effect than in the group of cooked beet). An increase in FMD (flow-mediated dilatation) was also observed, i.e. one of the most important indicators, for example, of progressing atherosclerosis, improved.
Intensive exercise induces an increase in proinflammatory cytokines TNFα and IL-1β and a dramatic increase in cytokine IL-6, which reacts to inflammation. This is balanced by the release of cytokine inhibitors (IL-1ra, sTNF-r1 and sTNF-r2) and anti-inflammatory cytokine IL-10. The study suggests that cytokine inhibitors and anti-inflammatory cytokines limit the size and duration of the inflammatory response to exercise. However, runners may think about drinking beetroot juice, which is able to reduce inflammation in the body.
Is long-distance running healthy? Certainly not.
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