Abstract
Vertical posture of a standing subject with different orientations of one or both feet was studied. Symmetrical turn of both feet in a standing person led to an increase in the movement of the common center of pressure (CCP) and center of pressure (CP) of each foot. It is likely that, for the vertical position maintenance with symmetrical feet turn, the movement of the CPs of both feet was controlled simultaneously. During standing with the turn of one foot, the CP movement increased for the foot that retained orientation in the sagittal direction. For the turned foot the CP movement did not change. Thus, the turn of the foot of one leg changed the involvement of this leg in the upright position maintenance. The vertical posture was maintained mainly due to the position control of CP of the foot oriented in the sagittal direction. In addition, there was a change in the predominant direction of the CP movement relative to the foot orientation. When the foot was oriented in the sagittal direction, the predominant movement direction of the CP was turned outward. With the foot rotated outward, the predominant movement direction of the CP was turned inward. This change in the CP movement direction was observed in the cases of simultaneous turn of both feet as well as the turn of one foot. It can be assumed that, in standing, the balance-maintaining system controls the CP position of each leg and takes into account the torsional torque in the leg that occurs when the foot is rotated.
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REFERENCES
Kirby, R.L., Price, N.A., and MacLeod, D.A., The influence of foot position on standing balance, J. Biomech., 1987, vol. 20, no. 4, p. 423.
Winter, D.A., Prince, F., Franck, J.S., et al., Unified theory regarding A/P and M/L balance in quiet standing, J. Neurophysiol., 1996, vol. 75, no. 6, p. 2334.
Sozzi, S., Honeine, J.L., Do, M.C., and Schieppati, M., Leg muscle activity during tandem stance and the control of body balance in the frontal plane, Clin. Neurophysiol., 2013, vol. 124, no. 6, p. 1175.
Vieira, T.M., Minetto, M.A., Hodson-Tole, E.F., and Botter, A., How much does the human medial gastrocnemius muscle contribute to ankle torques outside the sagittal plane? Hum. Mov. Sci., 2013, vol. 32, no. 4, p. 753.
Kazennikov, O.V. and Talis, V.L., Postural sway during body turn in symmetrical and asymmetrical standing in humans, Hum. Physiol., 2019, vol. 45, no. 4, p. 383.
Genthon, N. and Rougier, P., Influence of an asymmetrical body weight distribution on the control of undisturbed upright stance, J. Biomech., 2005, vol. 38, no. 10, p. 2037.
Kilby, M.C. and Newell, K.M., Intra- and inter-foot coordination in quiet standing: footwear and posture effects, Gait Posture, 2012, vol. 35, no. 3, p. 511.
Kazennikov, O.V., Kireeva, T.B., and Shlykov, V.Yu., Characteristics of the maintenance of the vertical posture during standing with an asymmetrical load on the legs, Hum. Physiol., 2013, vol. 39, no. 4, p. 392.
Rougier, P.R., How spreading the forefeet apart influences upright standing control, Motor Control, 2008, vol. 12, no. 4, p. 362.
McIlroy, W.E. and Maki, B.E., Preferred placement of the feet during quiet stance: development of a standardized foot placement for balance testing, Clin. Biomech. (Bristol), 1997, vol. 12, no. 1, p. 66.
Gibbons, C.T., Amazeen, P.G., and Likens, A.D., Effects of foot placement on postural sway in the anteroposterior and mediolateral directions, Motor Control, 2019, vol. 23, no. 12, p. 149.
Boumer, T.C., Martello, S.K., Devetak, G.F., et al., Influence of feet position on COP measures in post-stroke patients in quiet standing, Gait Posture, 2018, vol. 66, p. 58.
Gurfinkel, V., Cacciatore, T.W., Cordo, P., et al., Postural muscle tone in the body axis of healthy humans, J. Neurophysiol., 2006, vol. 96, no. 5, p. 2678.
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The study was partly supported by the Russian Foundation for Basic Research (project no. 18-015-00266).
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Statement of compliance with standards of research involving humans as subjects. All studies were carried out in accordance with the principles of biomedical ethics, formulated in the 1964 Declaration of Helsinki and its subsequent updates, and approved by the local bioethical committee of the Institute for Information Transmission Problems of the Russian Academy of Sciences (Moscow). Each study participant submitted voluntary written informed consent, signed by him after explaining to him the potential risks and benefits, as well as the nature of the forthcoming study.
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Kazennikov, O.V., Kireeva, T.B. & Shlykov, V.Y. Study of Vertical Posture of Humans Standing with Different Orientations of One or Both Feet. Hum Physiol 46, 492–499 (2020). https://doi.org/10.1134/S0362119720050059
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DOI: https://doi.org/10.1134/S0362119720050059