Acute and delayed effects of high intensity interval resistance training organization on cortisol and testosterone...

The use of high-intensity interval training (HIIT) is widely diffused as strategy to enhance aerobic fitness and body composition. In order to offer a more complete training, resistance exercises have been added to HIIT (HIIRT). Aims of our study were to characterize both heart rate and hormonal responses elicited by three different protocols of HIIRT having the same exercises, the same load and number of repetitions for each exercise.

Eight healthy trained men (28.61±3.51 years) performed three different workouts: exercise order, recovery and speed of execution were differently organized according to workout. Salivary samples were collected before and after each workout, at 11:00 p.m. and at 7:00 a.m. of the following day. Salive was also collected during a non-training day. Before and after the workout, plasma lactate was measured while a beat-to-beat heart rate recording was executed during each workout. Cortisol (C) and testosterone (T) were measured in salivary samples.

Workouts elicited the same heart rate response while random organization seems to elicit the highest lactate, C and T increases. Also when we studied the effects of workouts on prolonged hormones production we observed that workout organization influenced post-exercise hormonal production until the following morning modifying their physiological trend.

Even if exercises, load and number of repetitions were maintained fixed, exercise order, structured recovery and speed of execution determined different acute and prolonged effects. The knowledge of these responses is very important because may positively or negatively influence performance and health.