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N V Zimkin

Publications and source records attributed to N V Zimkin.

12 recordsLinked to original sources
PubMed1984

[Flexible and rigid connections in the regulation of motor activity].

The present investigation deals with the problem of versatile and rigid connections (N.P. Bechtereva), their functions and interrelations during repeated stereotype movements. The necessity of the versatile connections in the course of motor activity is demonstrated. Versatility depends on permanent variations of the contractile capacity of muscles during physical work as a result of fluctuations of the internal environment (intramuscular temperature, oxygen saturation, metabolite concentration), of a different initial elongation of muscle fubers and a simultaneous contraction of muscles not directly related to the test muscle activity. It was shown that different loadings and different levels of training lead to a variability of the relationship between rigid and versatile connections.

Electrophysiology↗
PubMed1984

[Structural variability of the functional system during activity and fatigue].

The object of the present paper is an analysis of factors causing considerable variability of functional systems (P. K. Anokhin) in their efferent part. This variability concerns the structure not only of different movements but has been established as well for similar repeated (cyclic, in particular) movements during work performed with the same working power. The problem of variability of the functional systems in fatigue is discussed.

Efficiency↗
PubMed1982

[Role of extrapolation and dynamic stereotype in the mechanisms of the formation and improvement of adequate motor coordinations].

Hardness (tonus), viscosity, bioelectric potentials, force and endurance of human muscles were studied. All these properties are subject to considerable alterations in conditions of fluctuations of muscle temperature, oxygen provision. They change permanently also in the process of dynamic work or static efforts (25, 50 and 75% of maximal strength). This is not in accordance with the mechanism of dynamic stereotype. The latter is conformed only to the succession of phases during standard movement performance. The intrinsic structure of motor activity, corresponding to the complex of active motor units, is permanently altered not only during work but in the restitution period as well. The nervous system due to its plasticity, has a high extrapolation capacity. It reacts adequately to new tasks arising with changes in the external or internal environment. Training improves extrapolation but after its cessation extrapolation becomes worse.

Electrophysiology↗
PubMed1979

[Effect of the contraction of other muscle groups on muscle strength, latency period and endurance].

The following investigation was undertaken in connection with Sechenov's idea on mutual influence of muscles performing different work. It deals with the influence on test muscle (TM) efficiency of other simultaneously working muscles (SWM). It was shown that tension of SWM or maintenance of complex postures exert a negative influence on the force and latency of the visual-motor reaction and the static effort endurance. The mechanism involved is external inhibition. After its extinction as a result of repeated combinations of both activities the degree of lowering of TM activity grows less and finally its improvement is observed as compared to data obtained in the absence of SWM contractions. It is suggested that when external inhibition is extinguished impulses arising in SWM reinforce and improve according to the law of dominant the functions of nervous centers regulating activities of the TM.

Humans↗