Plasma free and sulfoconjugated catecholamines concentration were measured in 19 male athlets (11 sprinters, 2 jumpers and 6 alpen skiers) to quantify the tolerance to cronicmental stress in competition.
　There was a negative correlation between the score of Trait Anxiety Inventory for sport (TAIS) and the basal leves of sulfoconjugated epinephrine (S-E, r=-.274), norepinephrine (S-NE, r=-.329) and dopamine (S-DA, r=-.322). In contrast, there were positive correlation be-tween the score of Diagnostic Inventory of Psychological-Competitive Ability for Athletes (DIPCA) and the basal levels of S-E (r=.286), S-NE (r=.317) and S-DA (r=.415). These correlations were not significant, but this may indicate a tendency that high score on TAIS indicate negative correlation, while high score on the DIPCA indicate positive correlaton with sulfoconjugated catecholamin (S-CA) concentrations.
　Following a 5 minutes mental arithmetic stress test, heart rate was increased during the test and remained increased 30 seconds after the test (p<.01). Plasma free epinephrine concentration was increased following the test, but significantly increase was shown only 3 minutes during the test (p<.05). However, plasma S-DA concentration decreased significantly both during the test and just before the end of stress session (p<.05). Changes in the other plasma CA concentrations were not observed following the test.
　These results may suggest that plasma S-CA could be an indicator of chronic activation of sympatho-adrenal system and therefore a possible measure of the tolerance to mental stress.

DESCENTE SPORTS SCIENCE Vol.18/THE DESCENTE AND ISHIMOTO MEMORIAL FOUNDATION FOR THE PROMOTION SPORTS SCIENCE