The objective is to define the effects of external (gravitational field) and internal factors on the functioning of the “shooter-weapons-aim” system.Materials and methods: the paper studied the shooters’ motor actions during the execution of exercises in trainings and at competitions. To characterize the shooter’s functional state, the study analyzed the work of the cardiovascular system, which was quantitatively characterized of the heart beat rate dynamically recorded on a Polar RS800 pulsometer with second-by-second time discretization.Results: The paper reviews the shooters’ complex coordination movements with regard to the systems within which energy and information exchange takes place against gravitational interactions. It used the relation between the system entropy variable and data entry. The increase in the information volume entered in the system from complementary sources conditions the decrease in the system uncertainty. Conclusions: the proposed approach allows to apply the general methods of research to studies of the “shooter-weapons-aim” system functioning with regard to energy-information and gravitational interaction. Specifying the quantitative characteristics when analyzing energy-information interaction reduces the system uncertainty and determines its functioning.