During the experiment, scientists analyzed the blood of athletes before and after races held in the French Alps at distances of 40 and 171 km. They measured numerous proteins, fats, metabolites, and trace elements both in plasma and inside red blood cells. The results were surprising even for the researchers, as reported by Studyfinds.
Red blood cells, which lack a nucleus and cannot regenerate, become vulnerable. If something is damaged in their structure, they can only function for a certain period before the spleen removes them. After 100-kilometer races, there is an increase in the levels of bilirubin and hypoxanthine—markers of cell destruction. At the same time, no such changes are observed after a 40-kilometer race.
It is known that the impact with the ground is one of the causes of red blood cell destruction; however, the study showed that this is only part of the problem. Inflammatory processes and oxidative stress play a much more significant role. The membrane fats of the cells undergo oxidation, similar to rancid oil, and the proteins inside the cells sustain damage that prevents them from functioning normally. As a result, the cells lose their flexibility and cannot pass through capillaries and the filters of the spleen.
After an ultramarathon, there is also a sharp increase in copper levels in the blood, which is associated with a decrease in the elasticity of red blood cells. Copper negatively affects cell membranes, and its source is likely related to the release of antioxidant enzymes that cannot cope with the load.
The most surprising discovery of the study is the analogy with donor blood. Blood in a bag ages according to the same principle: oxidation of proteins and fats, loss of flexibility, and increased likelihood of disposal after transfusion. Runners induce this process in their cells in one day, which corresponds to several weeks of storage in a blood bank. Researchers hope to use this data to develop methods for extending the shelf life of donor blood.
For athletes, this discovery emphasizes the importance of monitoring certain indicators. Vitamin B5 is actively consumed during the recovery of membranes, and carnitine plays a key role in the recovery of cells after long distances.
