Multivariate interrelationships of selected physiological and biochemical variables associated with physical fitness...

The interrelationships between selected physiological, metabolic and hormonal variables were investigated in active and sedentary middle-aged males during consecutive periods of rest, graded exercise on a bicycle ergometer, and recovery. Venous blood samples were drawn during each phase of the activity which was performed in the post-absorptive state. Data were analysed using correlational and factorial analysis techniques, and further evaluated by discriminant function procedures. Significant correlational relationships were evident among physiological, metabolic and hormonal variables, and factor analysis identified four factors at each phase of activity which accounted for as much as 69% of the common extracted variance. These factors described physiological function and hormone-metabolite behaviour during each phase of activity. Discriminant function allowed fitness classification of subjects using only the hormone-metabolite data, thus identifying specific biochemical correlates of the fitness groupings which had been established by physiological criteria alone.