Human urinary biogenic amines and some physiological responses during situation stress

Abstract

Using a shooting competition as a model, the effect of situation stress on self-assessed mental tension, urinary metanephrine, normetanephrine, 3-methoxy-4-hydroxymandelic acid, 4-hydroxy-3-methoxyphenyl acetic acid and 5-hydroxyindole acetic acid (5-HIAA), as well as heart rate (HR), systolic and diastolic blood pressure (SBP, DBP), skin conductance level (SCL) and electromyographic (EMG) parameters were studied in 7 male and 2 female champion rifle and (rapid-fire and air-)pistol shooters. The sample collection and recordings were carried out first in the training (baseline) circumstances and then during the competition. Self-assessed mental tension was higher than suitable during the competition but good performance was the expectation. During the competition, HR, SBP, DBP, SCL and EMG were increased significantly as compared with the baseline levels. No significant correlations between the variables and between the biogenic amine metabolite excretions were observed. The competition-induced changes in self-assessed mental tension correlated positively with the corresponding changes in SCL ( r=0.63), but negatively with changes in SBP ( r=-0.74). The HR of male rapid-fire pistol shooters was higher than that of male rifle shooters ( P < 0.05). All the urinary biogenic amine metabolite excretion levels were increased significantly as compared with the baseline values. Higher metabolite excretion was observed in rifle shooters than in rapid-fire shooters ( P<0.05). The correlation between catecholamine metabolites was significant ( r=0.67−0.93), but surprisingly the correlation between 5-HIAA and catecholamine metabolites was highly significant ( r=0.80−0.91). This study indicates a marked divergence in the behaviour of various stress-responsive variables during shooting competitions. The stress during competition seems to activate mental tension above a suitable level without any signs of overstimulation.