The effect of high-intensity interval training on lung parenchymal and non-parenchymal structural changes

The available information in relation to the effect of high-intensity interval training on lung structural changes are limited. The aim of this study was to evaluate the effect of a high-intensity interval training on structural changes in lung parenchymal and non-parenchymal tissue in male Wistar rats.
Samples of this study were 12 male Wistar rats (4 weeks old, 68±9 g), healthy, and had no history of disease and divided into training and control groups (exercise training = 6, control = 6). High-intensity interval training was carried out for 9 weeks. The samples started training program with 25 m/min (first week) and with 70 m/min at the end (ninth week). Finally, lung tissue was extracted for stereological and histological tests.
The findings showed that after 9 weeks of high-intensity interval training, parenchymal volume, number of alveoli and respiratory surface significantly decreased. Also, non-parenchymal and peribronchovascular volume significantly increased.
Based on research findings, it seems that 9 weeks of high-intensity interval training leads to lung inflammation and structural disorders. These effects are possibly associated with reduction of maximum gas exchange in lung blood-gas barrier during exercise performance and challenge of overall health in lung.