An estimation was carried out by factor analysis method of informative value of alpha-like rhythm, EEG theta-rhythm, local cerebral blood filling and oxygen tension (pO2) in estimation of functional state of cerebral structures under submaximal physical loads. Experiments were carried out on 35 rabbits with electrodes chronically implanted in the sensorimotor cortex and reticular formation. The obtained values were processed by a variant of factor analysis--a method of main components. For interpretation of factor loads matrix an orthogonal turn of factor axes was carried out according to varimax criterion. It has been established that informative value of the parameters depends on the brain structure where the given parameters were defined. Dynamics of pO2 and the theta-rhythm mostly influence the changes in other parameters. The states of structures before and during the period of physical load after-effect are mostly characterized by the brain local blood filling and less by the theta-rhythm amplitude.