High-intensity interval and moderate-intensity continuous training ameliorate the deteriorating acute effect of noise stress on corticosterone and testosterone in rats

Purpose: Noise has become an integral part of human life. Noise stress affect various physiological indices. In the present study, the effects of acute noise stress on corticosterone and testosterone and testosterone to cortisol ratio (T/C) in male rats, trained with two types of high-intensity interval training (HIIT) and moderate-intensity continuous training (MCT) were evaluated.

Methods: 42 male Wistar rats were divided randomly into seven groups, including the control group (C), control time (CT), exposure to acute noise stress (S), HIIT, MCT, HIIT with noise stress (HIIT + S), and MCT with noise stress (MCT + S). Exercise groups performed eight weeks of exercise training. One session of stress was induced in stress groups following the intervention (exercise or rest) period. Serum levels of corticosterone and T/C were measured through blood samples, taken 48 hours following the last session of exercise in the four exercise groups without noise stress and time control. Immediately after noise stress, blood samples were taken in 3 stress groups.

Results: Serum level of corticosterone in the MCT group was significantly higher than CT and HIIT groups (P = 0.001). Considering the effect of acute noise stress, corticosterone was significantly higher in HIIT + S and MCT + S, respectively, compared to the noise stress group (P < 0.001). Testosterone level of the noise stress group was significantly lower than CT group (P < 0.001). Testosterone level in the S group was significantly lower than other stress groups (MCT + S and HIIT + S) (P < 0.001). T/C in HIIT + S group was significantly higher compared to S and MCT + S groups (P < 0.001).

Conclusion: HIIT and MCT, by priority, ameliorated the deteriorating effect of noise stress on testosterone and T/C; and it appears that the intensity and mode of previous exercise training affect the hormonal response to noise stress.