Assessment of interleukin-6 level and lung inflammatory cells after high-intensity interval training and stay in hypoxic conditions

It seems that the effect of training on improving physical performance is not always associated with beneficial effects on internal organs. So far, the effects of high-intensity interval training and subsequent exposure to hypoxia have not been investigated on lung parenchyma. The purpose of this study was to investigate the effects of chronic hypoxia followed by high-intensity interval training on amount of lung inflammation.
Totally, 24 male Wistar rats (four weeks old, 71±4 gr) were randomly divided into four groups: 6-week control group (n=6), 6-week exercise group (n=6), 9-week control group (n=6), and exercises-hypoxia group (n=6). A training program (running on treadmill) was started with 25 meters per minute and was finished with 70 meters per minute. In each training session, rats performed the intense activity with 10 repetition times and two minutes of rest. The work to rest ratio was 1:2. After six weeks of interval training, rats were kept in a hypoxic chamber for three weeks. At the end, lung tissues extracted for stereological and immunohistochemistry analyses.
Both 6-weeks exercise and exercise-hypoxia groups indicated a significant increase in bronchus-associated lymphoid tissue (BALT), macrophage population and, IL-6 compared to the control group (p It seems a period of high-intensity interval training could possibly inflamed lung tissue. In addition, chronic hypoxia conditions may aggravate the inflammatory effects of intense exercise.