Effect of eccentric exercise on position sense at the human forearm in different postures.

This is a study of the ability of blindfolded human subjects to match the position of their forearms before and after eccentric exercise. The hypothesis tested was that the sense of effort contributed to forearm position sense. The fall in force after the exercise was predicted to alter the relationship between effort and force and thereby induce position errors. In the arms-in-front posture, subjects had their unsupported reference arm set to one of two angles from the horizontal, 30 or 60 degrees , and they matched its position by voluntary placement of their other arm. Matching errors were compared with a task where the arms were counterweighted, so could be moved in the vertical plane with minimal effort, and where the arms were moved in the horizontal plane. In these latter two tasks, the intention was to test whether removal of an effort sensation from holding the arm against gravity influenced matching performance. It was found that, although absolute errors for counterweighted and horizontal matching were no larger than for unsupported matching, their standard deviations, 6.1 and 6.8 degrees , respectively, were significantly greater than for unsupported matching (4.6 degrees ), indicating more erratic matching. The eccentric exercise led, the next day, to a fall in maximum voluntary muscle torque of >or=15%. This was accompanied by a significant increase in matching errors for the unsupported matching task from 2.7 +/- 0.5 to 0.8 +/- 0.7 degrees but not for counterweighted (1.4 +/- 0.2 to -0.2 degrees +/- 1.1 degrees ) or horizontal matching (-1.3 +/- 0.7 degrees to -1.8 +/- 0.7 degrees ). This, it is postulated, is because the reduced voluntary torque after exercise was accompanied by a greater effort required to support the arms, leading to larger matching errors. However, effort is only able to provide positional information for unsupported matching where gravity plays a role. In gravity-neutral tasks like counterweighted or horizontal matching, a change in the effort-force relationship after exercise leaves matching accuracy unaffected.

[1]  J R Lackner,et al.  Illusions of postural, visual, and aircraft motion elicited by deep knee in the increased gravitoinertial force phase of parabolic flight. Evidence for dynamic sensory-motor calibration to earth gravity force levels. , 1981, Experimental brain research.

[2]  K. Nosaka,et al.  Changes in markers of muscle damage of middle-aged and young men following eccentric exercise of the elbow flexors. , 2008, Journal of science and medicine in sport.

[3]  P. Percival,et al.  Force matching at the elbow joint is disturbed by muscle soreness , 2003, Somatosensory & motor research.

[4]  J. Frank,et al.  The effect of muscle vibration on human position sense during movements controlled by lengthening muscle contraction , 2004, Experimental Brain Research.

[5]  S. Gandevia.  Kinesthesia : roles for afferent signals and motor commands , 1996 .

[6]  S. Gandevia,et al.  Cutaneous receptors contribute to kinesthesia at the index finger, elbow, and knee. , 2005, Journal of neurophysiology.

[7]  U. Proske,et al.  Muscle damage from eccentric exercise: mechanism, mechanical signs, adaptation and clinical applications , 2001, The Journal of physiology.

[8]  G. E. Stelmach,et al.  The contribution of gravitational torques to limb position sense , 2004, Experimental Brain Research.

[9]  L R Young,et al.  Spatial orientation and posture during and following weightlessness: human experiments on Spacelab Life Sciences 1. , 1993, Journal of vestibular research : equilibrium & orientation.

[10]  J A Winter,et al.  Muscle spindle signals combine with the sense of effort to indicate limb position , 2005, The Journal of physiology.

[11]  U. Proske,et al.  Human forearm position sense after fatigue of elbow flexor muscles , 2004, The Journal of physiology.

[12]  J. D. Watson,et al.  Effects of externally imposed elastic loads on the ability to estimate position and force , 1984, Behavioural Brain Research.

[13]  D. McCloskey,et al.  Muscle sense and effort: motor commands and judgments about muscular contractions. , 1983, Advances in neurology.

[14]  D. Newham,et al.  Pain and fatigue after concentric and eccentric muscle contractions. , 1983, Clinical science.

[15]  J. Coast.  Handbook of Physiology. Section 12. Exercise: Regulation and Integration of Multiple Systems , 1997 .

[16]  Hermann von Helmholtz,et al.  Treatise on Physiological Optics , 1962 .

[17]  J. Lackner,et al.  Task-dependent motor learning , 2003, Experimental Brain Research.

[18]  D. McCloskey.  Kinesthetic sensibility. , 1978, Physiological reviews.

[19]  V. Gurfinkel,et al.  Effect of slow, small movement on the vibration-evoked kinesthetic illusion , 2005, Experimental Brain Research.

[20]  A. Vallbo,et al.  Human muscle spindle discharge during isometric voluntary contractions. Amplitude relations between spindle frequency and torque. , 1974, Acta physiologica Scandinavica.

[21]  L. Rowell,et al.  Exercise : regulation and integration of multiple systems , 1996 .

[22]  D. Jones,et al.  Mechanical influences on long‐lasting human muscle fatigue and delayed‐onset pain. , 1989, The Journal of physiology.

[23]  W. Rymer,et al.  Joint position sense: the effects of muscle contraction. , 1980, Brain : a journal of neurology.

[24]  J. Desmedt.  Motor control mechanisms in health and disease , 1983 .

[25]  U. Proske,et al.  Effect of muscle fatigue on the sense of limb position and movement , 2006, Experimental Brain Research.

[26]  J. Lackner,et al.  Illusions of postural, visual, and aircraft motion elicited by deep knee bends in the increased gravitoinertial force phase of parabolic flight , 1981, Experimental Brain Research.

[27]  J. E. Gregory,et al.  Responses of muscle spindles following a series of eccentric contractions , 2004, Experimental Brain Research.

[28]  U. Proske,et al.  Digital Object Identifier (DOI) 10.1007/s002210000380 RESEARCH ARTICLE , 2022 .

[29]  U. Proske,et al.  Warm-up stretches reduce sensations of stiffness and soreness after eccentric exercise. , 2005, Medicine & Science in Sports & Exercise.

[30]  U. Proske,et al.  Matching different levels of isometric torque in elbow flexor muscles after eccentric exercise , 2003, Experimental Brain Research.

[31]  D. Newham,et al.  Skeletal muscle stiffness and pain following eccentric exercise of the elbow flexors , 1987, Pain.

[32]  U. Proske,et al.  Effects of local pressure and vibration on muscle pain from eccentric exercise and hypertonic saline , 2003, Pain.