Influence of catecholamine activity on the hierarchical relationships among physical fitness condition and selected personality characteristics.

Tested male Ss (N = 34) to determine how changes in the urinary excretion patterns of selected catecholamines and their metabolites affect the multivariate relationships involving variables that measure physical fitness condition and selected personality characteristics. Urine specimens were collected from each S after sleep and during occupational activities and analyzed for six catecholamine-related variables. Those measures were combined with six personality variables (MMPI) and a physical fitness score (Ismail Criterion), and subjected to first- and second-order factor analyses. The findings indicated an association between low physical fitness and high self-reported anxious depression during the occupational period, but not at rest. The changes in the factor structures were statistically mediated by changes in the concentrations of the biochemical variables across the collection periods. This suggests that the relationships between physical fitness and personality are augmented during catecholamine reactivity to occupational stress.