[Interlimb interactions during cyclic in-phase and antiphased movements of arms and legs and their dependence on...

Coordinated movements of arms and legs suppose the neural interaction between the generators of the rhythmics of the upper and lower extremities. In the lying position in 10 healthy subjects activity of the muscles of the upper and lower extremities was recorded when separate and joint cyclic movements of the arms and legs with different phase relationships between the movements of the limbs were performed, and under various conditions of the motor task. Antiphased active arm movements were characterized by increased muscle activity than during in-phase mode. The activity of the arm muscles under passive movements, imposed by experimenter, was significantly less than their activity when passive movements of the arms were imposed by the other arm. When loading one arm the muscle activity in the other passively moving arm increased independently from the synergy of arm movements. During motor tasks, implementing joint antiphased movements as the upper and lower extremities, compared to motor task, implementing their joint in-phase movements, there has been a significant increase in activity in the biceps brahii muscle, the tibialis anterior muscle and biceps femoris muscle. Loading of arms in these motor tasks has been accompanied by increased activity in some of the leg muscles. Increasing of frequency of rhythmic movements resulted in a significant growth of the muscle activity of the arms and legs with their cooperative movements with greater rate of rise of flexor muscles activity for arms and legs during joint antiphased movements. Thus, the spatial organization of movements and kind of afferent influences are significant factors of interlimb interaction, which, in turn, determine the type of neural interconnections that are involved in the regulation of movements.