Background: Interleukin 6 (IL-6) has an inflammatory effect, and its concentration in serum increases during exercise. However, no studies have assessed acute changes in IL-6 concentration after consecutive days of extreme and long-term exercise.
Objective: This study aimed to assess acute changes in serum IL-6 concentration during four days of long-distance walking.
Methods: This prospective observational study assessed 25 athletes (aged 44.8 ± 9.1 years), who covered a total of 251 km in four days. Blood samples were collected daily to assess serum IL-6 concentrations. Repeated-measures analysis of variance (with Bonferroni’s post hoc test) and the Kruskal–Wallis H-test (with Dunn’s post hoc test) were used to investigate the differences between the measures.
Results: The serum IL-6 concentrations were higher on the four days of walking (1st day: 26.8 ± 14.8; 2nd day: 14 ± 7.4; 3rd day: 9.4 ± 10.8; 4th day: 4.5 ± 0.2 pg/mL) when compared to pre-walk values (pre-walk: 2.2 ± 2.1 pg/mL; p < 0.001). On the first day, there was a tenfold increase compared to the pre-walk value.
Conclusion: The inflammatory response increased the serum concentration of IL-6 after four days of exercise. With the passing of days, there were reductions but not to baseline values.



中文翻译：

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长距离步行四天白细胞介素6水平的急性变化

背景：白细胞介素 6 (IL-6) 具有炎症作用，运动期间其在血清中的浓度会增加。然而，没有研究评估连续几天的极端和长期运动后 IL-6 浓度的急剧变化。
目的：本研究旨在评估四天长距离步行期间血清 IL-6 浓度的急性变化。
方法：这项前瞻性观察性研究评估了 25 名运动员（年龄 44.8 ± 9.1 岁），他们在四天内共跑了 251 公里。每天收集血样以评估血清 IL-6 浓度。重复测量方差分析（使用 Bonferroni 的事后检验）和 Kruskal-Wallis H-test（与 Dunn 的事后检验）用于研究测量之间的差异。
结果：与步行 4 天相比，血清 IL-6 浓度较高（第 1 天：26.8 ± 14.8；第 2 天：14 ± 7.4；第 3 天：9.4 ± 10.8；第 4 天：4.5 ± 0.2 pg/mL）到步行前值（步行前：2.2 ± 2.1 pg/mL；p < 0.001）。第一天，与步行前的价值相比，增加了十倍。
结论：运动4天后炎症反应增加了血清IL-6浓度。随着时间的流逝，有所减少，但没有达到基线值。