ABSTRACT
<p><b>OBJECTIVE</b>To evaluate the stress level during parachuting training by salivary biomarker and to study the dynamic characteristics.</p><p><b>METHODS</b>Twenty recruits of military parachuting training completed 8 trainings in a month. The saliva samples were collected at 2 h and 1h before boarding and at 0.5 h after landing on the 1st, 4th and 7th trainings. The levels of cortisol, chromogranin A and α-amylase in saliva samples were detected.</p><p><b>RESULTS</b>The concentrations of cortisol, chromogranin A and activity of α-amylase increased significantly from pre-boarding to landing during 3 trainings. The concentrations of cortisol, chromogranin A and activity of α-amylase at 2 h before boarding and at 0.5 h after landing decreased significantly with the training times. However, the changes of 3 biomarkers at 1 h before boarding among 3 trainings were not significant.</p><p><b>CONCLUSION</b>The levels of stress increased significantly for 20 recruits from pre-boarding to landing during parachuting trainings. The stress levels of 20 recruits before boarding and after landing significantly decreased with parachuting training times.</p>