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Performance of individual crew members on postural tests consisting of standing for 50 s for two trials on a 3.2 and 5.7 cm rail. A score of 100 s is a perfect score. Note the drop in performance on the narrow rail on the first day of flight even with the eyes open. With the eyes closed, successful standing could be achieved after flight only on the wider rail. Note that the deficits in postural control were evident for at least 4 days after flight. The performance of two subjects was unaffected with the eyes open, while all subjects were affected with the eyes closed. The scale on the abscissa is nonlinear.
EMG amplitudes of the soleus and tibialis anterior muscles of a crew member on a 7 day shuttle flight (STS 51‐G) when standing with the shoes attached to the floor. The subject was asked to maintain a normal terrestrial standing posture or to lean 4° forward. This task was performed with normal vision, occluded vision, and stabilized vision. Because there were no qualitative differences among the three conditions, only the results from the normal vision tests are shown. In the relaxed upright posture position, the soleus EMG dropped slightly during flight relative to preflight and increased substantially immediately after flight. The EMG returned to preflight levels by 3 days postflight. The tibialis anterior EMG progressively increased during flight and was below preflight levels immediately after flight. These low levels persisted for 3 days postflight. Similar results were obtained from three other crew members from the same flight, although the data were not as complete as for the subject shown in this Figure. Similar results were evident in the 4° lean forward position.
Adapted from Clement et al.
The Achilles tendon was tapped with a device instrumented to record the impact force and the peak EMG response of the gastrocnemius‐soleus complex was recorded. Each slope was based on the average of 22 tendon taps for each of four conditions for one subject after a prolonged flight: (A) preflight and 2 days postflight, both ankles relaxed; and (B) preflight and 2 days postflight, when the contralateral calf muscles were voluntarily contracted. The tendon reflex threshold and gain were lower after flight than before flight. The relationships observed 2 days after flight were similar after 5 days (data not shown). Note in (B) that both prior to and after flight the gain of the relationship was reduced during contraction of the contralateral calf muscles, suggesting a contralateral inhibitory effect.
Adapted from Kozlovskaya et al.
Maximum EMG response from a patellar tendon tap of the right and left legs of two cosmonauts (AGN and VIS) before and after an 18 day flight (Soyuz‐9). Note that compared to preflight values the reflex amplitude is clearly higher 2 days after flight, but not thereafter.
The peak Hoffman‐reflex amplitude from the soleus muscle induced by stimulating the popliteal nerve with a subcutaneous needle electrode (cathode) and recorded from three subjects during a drop from a 15 cm stool before flight, on flight days 1 and/or 6, and from 1 to 6 days postflight. The data are expressed as a percentage change from a “hanging position.” Two different percentage change scales are shown. Note the absence of a change in the reflex on the first day of the mission, the drop seen in two subjects on flight day 6, and the elevated response postflight. The day of landing is 0 postflight day.
Adapted from Reschke et al.
Cosmonauts on Salyut‐6 and 7 and on the Mir station stayed in space for 60–366 days. Upon return to 1G, a series of motor tests (2–4 days postflight) were administered and a cumulative rank of the motor effects based on these tests was calculated for each of the 24 cosmonauts. A rank of 1 represents the cosmonaut showing the least effects of spaceflight, that is, the best performance. These tests have been described in detail previously . Briefly, the tests included the following: (1) maximal torque‐velocity output and a fatigue test during which the subjects worked isokinetically at 120°/s for a specific number of repetitions . These tests were conducted on the knee and ankle musculature; (2) posture tests in which EMG was measured during a series of standing tasks under varying conditions, for example, eyes opened or closed, Rhomberg standing, push response; and (3) reflex testing, principally the Achilles tendon reflex. All tests were performed using an anti‐G suit to minimize the potential complication of orthostatic tolerance in the performance and interpretation of the motor tasks. In the lower graph, the relative volume of exercise performed during the flight is associated with the flight duration.
Adapted from Koslovskaya et al.
Maximal voluntary torques during ankle plantarflexion produced by five cosmonauts 2–4 days after flights of 45–366 days. The torques represent the maximum effort during a constant velocity (isokinetic) movement. d, duration of flight in days.
1. Alford, E. K., R. R. Roy, J. A. Hodgson, and V. R. Edgerton. Electromyography of rat soleus, medial gastrocnemius and tibialis anterior during hindlimb suspension. Exp. Neurol. 96: 635–649, 1987.
2. Anzil, A. P., G. Sancesario, R. Massa, and G. Bernardi. Myofibrillar disruption in the rabbit soleus muscle after one‐week hindlimb suspension. Muscle Nerve 14: 358–369, 1991.
3. Babji, P., and F. W. Booth. α‐Actin and cytochrome c mRNAs in atrophied adult rat skeletal muscle. Am. J. Physiol. 254 (Cell Physiol. 23): C651–C656, 1988.
4. Babji, P., and F. W. Booth. Clenbuterol prevents or inhibits loss of specific mRNAs in atrophying rat skeletal muscle. Am. J. Physiol. 254 (Cell Physiol. 23): C657–C660, 1988.
5. Baldwin, K. M., R. E. Herrick, and S. A. McCue. Substrate oxidation capacity in rodent skeletal muscle: effects of exposure to zero gravity. J. Appl. Physiol. 75: 2466–2470, 1993.
6. Baldwin, K. M., R. E. Herrick, E. Ilyina‐Kakueva, and V. S. Oganov. Effects of zero gravity on myofibril content and iso‐myosin distribution in rodent skeletal muscle. FASEB J. 4: 79–83, 1990.
7. Baldwin, K. M., R. R. Roy, R. D. Sacks, C. Blanco, and V. R. Edgerton. Relative independence of metabolic enzymes and neuromuscular activity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 56: 1602–1607, 1984.
8. Baldwin, K. M., D. B. Thomason, H. Phan, R. R. Roy, and V. R. Edgerton. Myosin isoform distribution in mammalian skeletal muscles: effects of altered usage. In: Biochemical Aspects of Physical Exercise, edited by G. Benzi, L. Packer, and N. Siliprandi. Amsterdam, Elsevier, 1986, p. 15–26.
9. Baldwin, K. M., V. Valdez, R. E. Herrick, A. M. Macintosh, and R. R. Roy. Biochemical properties of overloaded fast‐twitch skeletal muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 52: 467–472, 1982.
10. Barany, M., ATPase activity of myosin correlated with speed of muscle shortening. J. Gen. Physiol. 50: 197–218, 1967.
11. Bell, G. J., T. P. Martin, E. I. Ilyina‐Kakueva, V. S. Oganov, and V. R. Edgerton. Altered distribution of mitochondria in rat soleus muscle fibers after spaceflight. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73: 493–497, 1992.
12. Blewett, C. and G. C. B. Elder. Quantitative EMG analysis in soleus and plantaris during hindlimb suspension and recovery. J. App. Physiol. 74: 2057–2066, 1993.
13. Bodine‐Fowler, S. C., R. R. Roy, W. Rudolph, N. Haque, I. B. Kozlovskaya, and V. R. Edgerton. Spaceflight and growth effects on muscle fibers in the rhesus monkey. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 82S–89S, 1992.
14. Bonen, A., C. Blewett, J. C. McDermott, and G. C. B. Elder. A model for nonexercising hindlimb muscles in exercising animals. Can. J. Physiol. Pharmacol. 68: 914–921, 1990.
15. Bonen, A., G. C. B. Elder, and M. H. Tan. Hindlimb suspension increases insulin binding and glucose metabolism. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 1833–1839, 1988.
16. Booth, F. W., Perspectives on molecular and cellular exercise physiology. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 1461–1471, 1988.
17. Booth, F. W., and C. R. Kirby. Changes in skeletal muscle gene expression consequent to altered weight bearing. Am. J. Physiol. 262 (Regulatory Integrative Comp. Physiol. 33): R329–R332, 1992.
18. Booth, F. W., J. K. Linderman, and C. R. Kirby. Molecular mechanisms of muscle disuse atrophy (and strategies of prevention). In: Medicine and Sport Science. Integration of Medical and Sports Sciences, edited by Y. Sato, J. Poortsmans, I. Hashimoto, and Y. Oshida. Basel: Karger, 1992, vol. 37, p. 142–149.
19. Booth, F. W., and D. B. Thomason. Molecular and cellular adaptation of muscle in response to exercise: perspectives of various models. Physiol Rev. 71: 541–585, 1991.
20. Bottinelli, R., S. Schiaffino, and C. Reggiani. Force‐velocity relationships and myosin heavy chain isoform compositions of skinned fibres from rat skeletal muscle. J. Physiol. (Land), 437: 655–672, 1991.
21. Brasil‐Neto, J. P., L. G. Cohen, A. Pascual‐Leone, F. K. Jabir, R. T. Wall, and M. Hallett. Rapid reversible modulation of human motor outputs after transient deafferentation of the forearm: A study with transcranial magnetic stimulation. Neurology 42: 1302–1306, 1992.
22. Burke, R. E., D. N. Levine, M. Salcman, and P. Tsairis. Motor units in cat soleus muscle: Physiological, histochemical and morphological characteristics. J. Physiol. (Lond) 238: 503–514, 1974.
24. Caiozzo, V. J., M. J. Baker, R. E. Herrick, M. Tao, and K. M. Baldwin. Effect of spaceflight on skeletal muscle: mechanical properties and myosin isoform content of a slow muscle. J. Appl. Physiol. 76: 1764–1773, 1994.
25. Chalmers, G. R., R. R. Roy, and V. R. Edgerton. Motoneuron and muscle fiber succinate dehydrogenase activity in control and overloaded plantaris. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 71: 1589–1592, 1991.
26. Chalmers, G. R., R. R. Roy, and V. R. Edgerton. Adaptibility of the oxidative capacity of motoneurons. Brain Res. 570: 1–10, 1992.
27. Chekirda, I. F., R. B. Bogdashevskiy, A. V. Yeremin, and I. A. Kolosov. Coordination structure of walking of Soyuz‐9 crew members before and after flight. Kosm. Biol. Aviakosm. Med. 5: 48–52, 1970.
28. Cherepakhin, M. A., and V. I. Pervushin. Space flight effect on the neuromuscular system of cosmonauts. Kosm. Biol. Aviakosm. Med. 4: 46–49, 1970.
29. Chi, M. M. Y., R. Choksi, P. Nemeth, I. Krasnov, E. Ilyina‐Kakueva, J. K. Manchester, and O. Lowry. Effects of microgravity and tail suspension on enzymes of individual soleus and tibialis anterior fibers. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 66S–73S, 1992.
30. Chui, L. A., and K. R. Castleman. Morphometric analysis of rat muscle fibers following space flight and hypogravity. Physiologist 23 (Suppl): S76–S78, 1980.
31. Clement, G., and C. Andre‐Deshays. Motor activity and visually induced postural reactions during two‐g and zero‐g phases of parabolic flight. Neurosci. Lett. 79: 113–116, 1987.
32. Clement, G., V. S. Gurfinkel, and F. Lestienne. Mechanisms of posture maintenance in weightlessness. In: Vestibular and Visual Control of Posture and Locomotor Equilibrium, edited by M. Igarashi and I. Black. Basel: Karger, 1985, p. 158–163.
33. Clement, G., and F. Lestienne. Adaptive modifications of postural attitude in conditions of weightlessness. Exp. Brain Res. 72: 381–389, 1988.
34. Cohen, M. M., Perception and action in altered gravity. In: Sensing and Controlling Motion: Vestibular and Sensorimotor Function, edited by B. Cohen, D. Tomko, and F. Guedry. Ann. N. Y. Acad. Sci. 656: 354–362, 1992.
35. Convertino, V. A., Physiological adaptations to weightlessness: effects of exercise and work performance. In: Exercise and Sport Science Reviews, edited by K. B. Pandolf and J. O. Holloszy. Baltimore, MD: Williams and Wilkins, 1990, p. 119–166.
36. Convertino, V. A., Exercise and adaptation to microgravity environments. In: Handbook of Physiology. Environmental Physiology, edited by M. J. Fregly and C. M. Blatteis. New York: Oxford University Press, Chapt. 36, 000–000, 1995.
37. Corley, K., N. Kowalchuk, and A. J. McComas. Contrasting effects of suspension on hind limb muscles in the hamster. Exp. Neurol. 85: 30–40, 1984.
38. D'Amelio, F., and N. G. Daunton. Effects of spaceflight in the adductor longus muscle of rats flown in the Soviet Biosatellite COSMOS 2044. A study employing neural cell adhesion molecule (N‐CAM) immunocytochemistry and conventional morphological techniques (light and electron microscopy). J. Neuropathol. Exp. Neurol. 51: 415–431, 1992.
39. Darr, K. C., and E. Schultz. Hindlimb suspension suppresses muscle growth and satellite cell proliferation. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 67: 1827–1834, 1989.
40. D'Aunno, D. S., R. R. Robinson, G. S. Smith, D. B. Thomason, and F. W. Booth. Intermittent acceleration as a countermeasure to soleus atrophy. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 72: 428–433, 1992.
41. D'Aunno, D. S., D. B. Thomason, and F. W. Booth. Centrifugal intensity and duration as countermeasures to soleus muscle atrophy. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 69: 1387–1389, 1990.
42. Desplanches, D., S. R. Kayar, B. Sempore, R. Flandrois, and H. Hoppeler. Rat soleus muscle ultrastructure after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 69: 504–508, 1990.
43. Desplanches, D., M. H. Mayet, E. I. Ilyina‐Kakueva, B. Sempore, and R. Flandrois. Skeletal muscle adaptation in rats flown on Cosmos 1667. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 48–52, 1990.
44. Desplanches, D., M. H. Mayet, B. Sempore, and R. Flandrois. Structural and functional responses to prolonged hindlimb suspension in rat muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 558–563, 1987.
45. Desplanches, D., M. H. Mayet, B. Sempore, J. Frutoso, R. Flandrois. Effect of spontaneous recovery or retraining after hindlimb suspension on aerobic capacity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 1739–1743, 1987.
46. Diffee, G. M., V. J. Caiozzo, R. E. Herrick, and K. M. Baldwin. Contractile and biochemical properties of rat soleus and plantaris after hindlimb suspension. Am. J. Physiol. 260 (Cell Physiol. 31): C528–C534, 1991.
47. Diffee, G. M., F. Haddad, R. E. Herrick, and K. M. Baldwin. Control of myosin heavy chain expression: interaction of hypothyroidism and hindlimb suspension. Am. J. Physiol. 261 (Cell Physiol. 32): C1099–C1106, 1991.
48. Doty, S. B., E. R. Morey‐Holton, G. N. Durnova, and A. S. Kaplansky. Morphological studies of bone and tendon. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. (Suppl.): 10S–13S, 1992.
49. Duysens, J., and K. G. Pearson. Inhibition of flexor burst generation by loading ankle extensor muscles in walking cats. Brain Res. 187: 321–332, 1980.
50. Dyhre‐Poulson, P., E. B. Simonsen, and M. Voigt. Dynamic control of muscle stiffness and H reflex modulation during hopping and jumping in man. J. Physiol. (Lond) 437: 287–304, 1991.
51. Edgerton, V. R. and R. R. Roy. Regulation of skeletal muscle fiber size, shape and function. J. Biomech. 24 (Suppl. 1): 123–133, 1991.
52. Edgerton, V. R., and R. R. Roy. Nervous system and sensory adaptation: neural plasticity associated with chronic neuromuscular activity. In: Physical Activity, Fitness, and Health: International Proceedings and Consensus Statement, edited by C. Bouchard, R. J. Shephard, and T. Stephens. Champaign, IL: Human Kinetics, 1994, 2nd Edition, chapt. 34, p. 511–520.
53. Edgerton, V. R., and R. R. Roy. Adaptations of skeletal muscle to spaceflight. In: Fundamentals of Space Life Sciences, edited by S. Churchill. Malabar, FL: Kreiger. (in Press), 1995.
54. Edgerton, V. R., R. R. Roy, L. Eldridge, and M. Liebhold. Maintenance of differences in fatigability of slow and fast muscle with prolonged inactivity. Med. Sci. Sports Exerc. 13: 87, 1981.
55. Edgerton, V. R., R. R. Roy, R. J. Gregor, C. L. Hager, and T. Wickiewicz. Muscle fiber activation and recruitment. In: Biochemistry of Exercise, International Series of Sports Sciences, edited by H. Knuttgen, J. Vogel, and J. Poortmans. Champaign, IL: Human Kinetics, 1983, p. 31–49.
56. Edgerton, V. R., R. R. Roy. Neuromuscular adaptations to actual and simulated weightlessness. In: Advances in Space Biology and Medicine, edited by S. L. Bonting. Greenwich, CT: Jai Press, 1994, vol. 4, p. 33–67.
57. Edgerton, V. R., M.‐Y. Zhou, Y. Ohira, H. Klitgaard, B. Jiang, B. Bell, B. Harris, B. Saltin, P. D. Gollnick, R. R. Roy, M. K. Day, and M. Greenhisen. Human fiber size and enzymatic properties after 5 and 11 days of spaceflight. J. Appl. Physiol. 78: 1733–1739, 1995.
58. Elder, G. C. B., and A. McComas. Development of rat muscle during short‐ and long‐term hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 62: 1917–1923, 1987.
59. Fell, R. D., L. B. Gladden, J. M. Steffen, and X. J. Musacchia. Fatigue and contraction of slow and fast muscles in hypoki‐netic/hypodynamic rats. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 58: 65–69, 1985.
60. Fell, R. D., J. M. Steffen, and X. J. Musacchia. Effect of hypokinesia‐hypodynamia on rat muscle oxidative capacity and glucose uptake. Am. J. Physiol. 249 (Regulatory Integrative Comp. Physiol. 20): R308–R312, 1985.
61. Fitts, R. F., C. J. Brimmer, A. Heywood‐Cooksey, and R. J. Timmerman. Single muscle fiber enzyme shifts with hindlimb suspension and immobilization. Am. J. Physiol. 256 (Cell Physiol. 27): C1082–C1091, 1989.
62. Fitts, R. H., J. M. Metzger, D. A. Riley, and B. R. Unsworth. Models of disuse: a comparison of hindlimb suspension and immobilization. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 60: 1946–1953, 1986.
63. Flynn, D. E., and S. R. Max. Effects of suspension hypokinesia/hypodynamia on rat skeletal muscle. Aviat. Space Environ. Med. 56: 1065–1069, 1985.
64. Gardetto, P. R., J. M. Schluter, and R. H. Fitts. Contractile function of single muscle fibers after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 66: 2739–2749, 1989.
65. Gardiner, P., R. Michel, C. Browman, and E. Noble. Increased EMG of rat plantaris during locomotion following surgical removal of its synergists. Brain Res. 380: 114–121, 1986.
66. Garshnek, V., Soviet space flight: The human element. Aviat. Space Environ. Med. 60: 695–705, 1989.
69. Gazenko, O. G., A. I. Grigoriev, and I. B. Koslovskaya. Mechanisms of acute and chronic effects of microgravity. Physiologist 30 (Suppl. 1): S1–S5, 1987.
70. Gazenko, O. G., A. I. Grigor'yev, and A. D. Yegorov. Medical investigations of long‐term manned space flight on‐board Salyut‐7–Soyuz‐T. Kosm. Biol. Aviakosm. Med. 24: 9–15, 1990.
71. Gevlich, G. I., L. S. Grigorieva, M. K. Bojko, and I. B. Koslovskaya. Measurement of skeletal muscle tone by recording transverse stiffness. Kosm. Biol. Aviakosm. Med. 5: 86–89, 1983.
72. Goldspink, D. F., A. J. Morton, P. Loughna, and G. Goldspink. The effect of hypokinesia and hypodynamia on protein turnover and the growth of four skeletal muscles of the rat. Pflugers Arch. 407: 333–340, 1986.
73. Gorbunova, A., and V. V. Portugalov. Cytochemical investigations of proteins and RNA in spinal motoneurons and neurons of spinal ganglia of the rat after space flight. Aviat. Space Environ. Med. 47: 708–710, 1976.
74. Graham, S. C., R. R. Roy, E. O. Hauschka, and V. R. Edgerton. Effects of weight support on medial gastrocnemius fibers of suspended rats. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 67: 945–953, 1989.
75. Graham, S. C., R. R. Roy, C. Navarro, B. Jiang, D. Pierotti, S. Bodine‐Fowler, and V. R. Edgerton. Enzyme and size profiles in chronically inactive cat soleus muscle fibers. Muscle Nerve 15: 27–36, 1992.
76. Graham, S. C., R. R. Roy, S. P. West, D. Thomason, and K. M. Baldwin. Exercise effects on the size and metabolic properties of soleus fibers in hindlimb‐suspended rats. Aviat. Space Environ. Med. 60: 226–234, 1989.
77. Green, H., M. Morikawa, and T. Nixon. A dual effector theory of growth‐hormone action. Differentiation 29: 195–198, 1985.
78. Greenleaf, J. E., Physiological responses to prolonged bed rest and fluid immersion in humans. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 57: 619–633, 1984.
79. Greenleaf, J. E., R. Bulbulian, E. M. Bernauer, W. L. Haskell, and T. Moore. Exercise‐training protocols for astronauts in microgravity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 67: 2191–2204, 1989.
80. Greenleaf, J. E., and S. Kozlowski. Physiological consequences of reduced physical activity during bed rest. In: Exercise and Sports Science Reviews, edited by R. L. Terjung. Philadelphia: Franklin Institute Press, 1982, vol. 10, p. 84–119.
81. Grigor'yev, A. I., S. A. Bugrov, V. V. Bogomolov, A. D. Yegorov, I. B. Koslovskaya, I. D. Pestov, and I. K. Tarasov. Review of the major medical results of the 1‐year flight on space station “Mir”. Kosm. Biol. Aviakosm. Med. 5: 3–10, 1990.
82. Grigoryeva, L. S., and I. B. Kozlovskaya. Effect of microgravity and hypokinesia on the velocity and strength properties of man's muscles. Kosm. Biol. Aviakosm. Med. 21: 27–30, 1987.
83. Grindeland, R., T. Fast, M. Ruder, M. Vasques, P. Lundgren, S. Scibetta, J. Tremor, P. Buckendahl, L. Keil, O. Chee, T. Reilly, B. Dalton, and P. Callahan. Rodent body, organ, and muscle weight responses to seven days of microgravity. Physiologist 28: 375, 1985.
84. Grindeland, R. E., W. C. Hymer, M. Farrington, T. Fast, C. Hayes, K. Motter, L. Patil, and M. Vasques. Changes in pituitary growth hormone cells prepared from rats flown on Spacelab 3. Am. J. Physiol. 252 (Regulatory Integrative Comp. Physiol. 23): R209–R215, 1987.
85. Grindeland, R. E., R. R. Roy, V. R. Edgerton, E. J. Grossman, V. R. Mukku, B. Jiang, D. J. Pierotti, and I. Rudolph. Interactive effects of growth hormone and exercise on muscle mass in suspended rats. Am. J. Physiol. 267 (Regulatory Integrative Comp. Physiol. 36): R316–R322, 1994.
86. Gross, Y., and R. Melzack. Body image: dissociation of real and perceived limbs by pressure‐cuff ischemia. Exp. Neurol. 61: 680–688, 1978.
87. Gurfinkel, V. S., Y. S. Levik, K. E. Popov, B. N. Smetanin, and V. Y. Shlikov. Body scheme in the control of postural activity. In: Stance and Motion: Facts and Concepts, edited by V. S. Gurfinkel, M. E. Ioffe, J. Massion, and J. P. Roll. New York: Plenum, 1988, p. 185–193.
88. Haida, N., W. M. Fowler, Jr., R. T. Abresch, D. B. Larson, R. B. Sharman, R. G. Taylor, and R. K. Entrikin. Effect of hindlimb suspension on young and adult skeletal muscle. 1. Normal mice. Exp. Neurol. 103: 68–76, 1989.
89. Hauschka, E. O., R. R. Roy, and V. R. Edgerton. Size and metabolic properties of single muscle fibers in rat soleus after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 62: 2338–2347, 1987.
90. Hauschka, E. O., R. R. Roy, and V. R. Edgerton. Periodic weight support effects on rat soleus fibers after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 1231–1237, 1988.
91. Henneman, E., and L. M. Mendell. Functional organization of motoneuron pool and its input. In: Handbook of Physiology. The Nervous System: Motor Control, edited by B. Brookhart, V. B. Mountcastle, V. B. Brooks, and S. R. Geiger. Bethesda, MD: Am. Physiol. Soc., 1981, sect. 1, vol. II, pt. 1, chptr. 11 p. 423–507.
92. Henriksen, E. J., K. J. Rodnick, C. E. Mondon, D. E. James, and J. O. Holloszy. Effect of denervation or unweighting on GLUT‐4 protein in rat soleus muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 70: 2322–2327, 1991.
93. Henriksen, E. J., and M. E. Tischler. Glucose uptake in rat soleus: effect of acute unloading and subsequent reloading. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 64: 1428–1432, 1988.
94. Henriksen, E. J., and M. E. Tischler. Time course of the response of carbohydrate metabolism to unloading of the soleus. Metabolism 37: 201–208, 1988.
95. Henriksen, E. J., M. E. Tischler, and D. G. Johnson. Increased response to insulin of glucose metabolism in the 6‐day unloaded rat soleus muscle. J. Biol. Chem. 15: 10707–10712, 1986.
96. Herbert, M. E., R. R. Roy, and V. R. Edgerton. Influence of one week of hindlimb suspension and intermittent high load exercise on rat muscles. Exp. Neurol. 102: 190–198, 1988.
97. Hodgson, J. A., S. C. Bodine‐Fowler, R. R. Roy, R. D. De Leon, C. P. De Guzman, I. Koslovskaya, M. Sirota, and V. R. Edgerton. Changes in recruitment of Rhesus soleus and gastrocnemius muscles following a 14 day spaceflight. Physiologist 34 (Suppl.): S102–S103, 1991.
98. Hoffmann, S. J., R. R. Roy, C. E. Blanco, and V. R. Edgerton. Enzyme profiles of single fibers never exposed to normal neuromuscular activity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 69: 1150–1158, 1990.
99. Hoh, J. F. Y., and C. J. Chow. The effect of the loss of weight‐bearing function on the isomyosin profile and contractile properties of rat skeletal muscles. In: Molecular Pathology of Nerve and Muscle, edited by A. D. Kidman, J. K. Tomkins, C. A. Morris, and N. A. Cooper. Clifton, N. J.: Humana, 1983, p. 371–383.
100. Holy, X., and Y. Mounier. Effects of short spaceflights on mechanical characteristics of rat muscles. Muscle Nerve 14: 70–78, 1991.
101. Homick, J. L., and M. F. Reschke. Postural equilibrium following exposure to weightless space flight. Acta Otolaryngol. 83: 455–464, 1977.
102. Howard, G., J. M. Steffen, and, T. E. Geoghegan. Transcriptional regulation of decreased protein synthesis during skeletal muscle unloading. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 66: 1093–1098, 1989.
103. Hutchison, D. L., R. R. Roy, S. Bodine‐Fowler, J. A. Hodgson, and V. R. Edgerton. EMG amplitude in the proximal and distal compartments of the cat semitendinosus during various motor tasks. Brain Res. 479: 56–64, 1989.
104. Hutchison, D. L., R. R. Roy, J. A. Hodgson, and V. R. Edgerton. EMG amplitude relationships between the rat soleus and medial gastrocnemius during various motor tasks. Brain Res. 502: 233–244, 1989.
105. Hutton, R. S., and S. W. Atwater. Acute and chronic adaptations of muscle proprioceptors in response to increased use. Sports Med. 14: 406–421, 1992.
106. Ilyina‐Kakueva, E. I., V. V. Portugalov, and N. P. Krivenkova. Space flight effects on the skeletal muscle of rats. Aviat. Space Environ. Med. 47: 700–703, 1976.
107. Ishihara, A., H. Naitoh, H. Araki, and Y. Nishihira. Soma size and oxidative enzyme activity of motoneurones supplying the fast twitch and slow twitch muscles of the rat. Brain Res. 446: 195–198, 1988.
108. Jaspers, S. R., J. Fagan, S. Satarug, P. Cook, and M. E. Tischler. Effects of immobilization on rat hind limb muscles under non‐weight‐bearing conditions. Muscle Nerve 11: 458–466, 1988.
109. Jaspers, S. R., J. M. Fagan, and M. E. Tischler. Biochemical response to chronic shortening in unloaded soleus muscles. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 59: 1159–1163, 1985.
110. Jaspers, S. R., E. J. Henriksen, S. Satarug, and M. E. Tischler. Effects of stretching and disuse on amino acids in muscles of rat hind limbs. Metabolism 38: 303–310, 1989.
111. Jaspers, S. R., S. Jacob, and M. E. Tischler. Metabolism of amino acids by the atrophied soleus of tail‐casted, suspended rats. Metabolism 35: 216–223, 1986.
112. Jaspers, S. R., and M. E. Tischler. Role of glucocorticoids in the response of rat leg muscles to reduced activity. Muscle Nerve 9: 554–561, 1986.
113. Jiang, B., Y. Ohira, R. R. Roy, Q. Nguyen, E. I. Ilyina‐Kakueva, V. Oganov, and V. R. Edgerton. Adaptation of fibers in fast‐twitch muscles of rats to spaceflight and hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 58S–65S, 1992.
114. Jiang, B., R. R. Roy, and V. R. Edgerton. Enzymatic plasticity of medial gastrocnemius fibers in the adult chronic spinal cat. Am. J. Physiol. 259 (Cell Physiol. 30): C507–C514, 1990.
115. Jiang, B., R. R. Roy, and V. R. Edgerton. Expression of a fast fiber enzyme profile in the cat soleus after spinalization. Muscle Nerve 13: 1037–1049, 1990.
116. Jiang, B., R. R. Roy, C. Navarro, and V. R. Edgerton. Atrophic response of rat soleus fibers subjected to a 4‐day spaceflight. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 74: 527–531, 1993.
117. Jiang, B., R. R. Roy, C. Navarro, Q. Nguyen, D. Pierotti, and V. R. Edgerton. Enzymatic responses of cat medial gastrocnemius fibers to chronic inactivity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 70: 231–239, 1990.
118. Jiang, B., R. R. Roy, I. V. Polyakov, I. B. Krasnov, and V. R. Edgerton. Ventral horn cell responses to spaceflight and hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 107S–111S, 1992.
119. Jolesz, F., and F. A. Sreter. Development, innervation, and activity‐pattern induced changes in skeletal muscle. Ann. Rev. Physiol. 43: 531–552, 1981.
122. Kandarian, S. C., R. C. Boushel, and L. H. Schulte. Elevated interstitial volume in rat soleus muscles by hindlimb unweighting. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 71: 910–914, 1991.
123. Kandarian, S., S. O'Brien, K. Thomas, L. Schulte, and J. Navarro. Regulation of skeletal muscle dihydropyridine receptor gene expression by biomechanical unloading. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 72: 2510–2514, 1992.
124. Kasper, C. E., T. P. White, and L. C. Maxwell. Running during recovery from hindlimb suspension induces transient muscle injury. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 533–539, 1990.
125. Kenyon, R. V., and L. R. Young. M.I.T./Canadian vestibular experiments on the Spacelab‐1 mission. 5. Postural responses following exposure to weightlessness. Exp. Brain Res. 64: 335–346, 1986.
126. Kirby, C. R., M. J. Ryan, and F. W. Booth. Eccentric exercise training as a countermeasure to non‐weight‐bearing soleus muscle atrophy. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73: 1894–1899, 1992.
127. Kirschbaum, B. J., H. B. Kucher, A. M. Kelly, and D. Pette. Effects of increased neuromuscular activity at altered thyroid hormone levels on myosin expression. In: The Dynamic State of Muscle Fibers, edited by D. Pette. Berlin: Walter de Gruyter, 1990, p. 473–479.
128. Koslovskaya, I. B., V. A. Barmin, V. I. Stepantsov, and N. M. Kharitonov. Results of studies of motor functions in long‐term space flights. Physiologist 33 (Suppl.): S1–S3, 1990.
129. Kozlovskaya, I. B., I. F. Dmitrieval, L. Grigorieva, A. Kirenskaya, and Y. Kreidich. Gravitational mechanisms in the motor system. Studies in real and simulated weightlessness. In: Stance and Motion: Facts and Concepts, edited by V. S. Gurfinkel, M. E. Ioffe, J. Massion, and J. P. Roll. New York: Plenum, 1988, p. 37–48.
130. Kozlovskaya, I. B., Y. V. Kreidich, V. S. Oganov, and O. P. Koserenko. Pathophysiology of motor functions in prolonged space flights. Acta Astronautica 8: 1059–1072, 1981.
131. Krippendorf, B. B., and D. A. Riley. Distinguishing unloading‐versus reloading‐induced changes in rat soleus muscle. Muscle Nerve 16: 99–108, 1993.
132. Kushmerick, M. J., Energetics of muscle contraction. In: Handbook of Physiology edited by S. R. Geiger, R. H. Adrian, and L. D. Peachey. Bethesda, MD: Am. Physiol. Soc., 1983, sect. 10: Skeletal Muscle, chapt. 7, p. 189–236.
133. Kushmerick, M. J., T. S. Moerland, and N. G. Wolf. Adaptive changes in myosin isoforms and in energy metabolism in muscles containing analogues of creatine as the phosphagen. In: The Dynamic State of Muscle Fibers, edited by D. Pette. Berlin: Walter de Gruyter, 1990, p. 551–566.
134. Lackner, J. R., and P. Dizio. Gravitoinertial force level affects the appreciation of limb position during muscle vibration. Brain Res. 592: 175–180, 1992.
135. Lackner, J. R., and A. Grabiel. Illusions of postural, visual, and aircraft motion elicited by deep knee bends in the increased gravitoinertial force phase of parabolic flight. Exp. Brain Res. 44: 312–316, 1981.
136. Lackner, J. R., and M. S. Levine. Changes in apparent body orientation and sensory localization induced by vibration of postural muscles: Vibratory myesthetic illusions. Aviat. Space Environ. Med. 50: 346–354, 1979.
137. Layne, C. S., and B. S. Spooner. EMG analysis of human postural responses during parabolic flight microgravity episodes. Aviat. Space Environ. Med. 61: 994–998, 1990.
138. LeBlanc, A., C. Marsh, H. Evans, P. Johnson, V. Schneider, and S. Jhingran. Bone and muscle atrophy with suspension of the rat. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 58: 1669–1675, 1985.
139. Lestienne, F. G., and V. S. Gurfinkel. Postural control in weightlessness: a dual process underlying adaptation to an unusual environment. TINS 11: 359–363, 1988.
140. Lestienne, F. G., and V. S. Gurfinkel. Posture as an organizational structure based on a dual process: a formal basis to interpret changes of posture in weightlessness. In: Progress in Brain Research, edited by O. Pompeiano and J. H. J. Allum. Amsterdam: Elsevier, 1988, vol. 76, p. 307–313.
141. Loughna, P., D. F. Goldspink, and G. Goldspink. Effects of hypokinesia and hypodynamia upon protein turnover in hindlimb muscles of the rat. Aviat. Space Environ. Med. 58: 133–138, 1987.
142. Loughna, P., G. Goldspink, and D. F. Goldspink. Effect of inactivity and passive stretch on protein turnover in phasic and postural rat muscles. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 61: 173–179, 1986.
143. Magus, R., Körpersfellung. Berlin: Springer‐Verlag, 1924, p. 540.
144. Manchester, J. K., M. M.‐Y. Chi, B. Norris, B. Ferrier, I. Krasnov, P. M. Nemeth, D. B. McDougal, Jr, and O. H. Lowry. Effect of microgravity on metabolic enzymes of individual muscle fibers. FASEB J. 4: 55–63, 1990.
145. Martin, T. P., Predictable adaptations by skeletal muscle mitochondria to different exercise training workloads. Comp. Biochem. Physiol. [B] 88: 273–276, 1987.
146. Martin, T. P., Protein and collagen content of rat skeletal muscle following space flight. Cell Tissue Res. 254: 251–253, 1988.
147. Martin, T. P., and V. R. Edgerton. Intrafiber distribution of succinate dehydrogenase in cat tibialis anterior motor units. Can. J. Physiol. Pharmacol. 70: 970–976, 1992.
148. Martin, T. P., V. R. Edgerton, and R. E. Grindeland. Influence of spaceflight on rat skeletal muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 2318–2325, 1988.
149. Matthews, P. B. C., Evolving views on the internal operation and functional role of the muscle spindle. J. Physiol. (Lond) 320: 1–30, 1981.
150. McCully, K. K., and J. A. Faulkner. Characteristics of lengthening contraction associated with injury to skeletal muscle fibers. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 61: 293–299, 1986.
151. McDonald, K. S., M. D. Delp, and R. H. Fitts. Fatigability and blood flow in the rat gastrocnemius‐plantaris‐soleus after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73: 1135–1140, 1992.
152. McDonald, K. S., M. D. Delp, and R. H. Fitts. Effect of hindlimb unweighting on tissue blood flow in the rat. J. Appl. Physiol: Respir. Environ. Exerc. Physiol. 72: 2210–2218, 1992.
153. McDonald, K. S., J. M. Schluter, A. L. Heywood‐Cooksey, and R. H. Fitts. Mechanism of hindlimb suspension induced changes in fiber Vmax and tension. Med. Sci. Sports Exerc. 22: S119, 1990.
154. Michel, R. N., and P. F. Gardiner. To what extent is hindlimb suspension a model of disuse? Muscle Nerve 13: 646–653, 1990.
155. Michel, R. N., A. E. Olha, and P. F. Gardiner. Influence of weight bearing on the adaptations of rat plantaris to ablation of its synergists. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 67: 636–642, 1989.
156. Miu, B., T. P. Martin, R. R. Roy, V. Oganov, E. Ilyina‐Kakueva, J. F. Marini, J. J. Leger, S. C. Bodine, and V. R. Edgerton. Metabolic and morphologic properties of single fibers in the rat after space flight, Cosmos 1887. FASEB J. 4: 64–72, 1990.
157. Money, K. E., and B. S. K. Cheung. Alterations of proprioceptive function in the weightless environment. J. Clin. Pharmacol 31: 1007–1009, 1991.
158. Morey, E. R., Spaceflight and bone turnover: correlation with a new rat model of weightlessness. Bioscience 29: 168–172, 1979.
159. Musacchia, X. J., D. R. Deavers, G. A. Meininger, and T. P. Davis. A model for hypokinesia: effects on muscle atrophy in the rat. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 48: 479–486, 1980.
160. Musacchia, X. J., J. M. Steffen, and D. R. Deavers. Rat hindlimb muscle responses to suspension hypokinesia/hypodynamia. Aviat. Space Environ. Med. 54: 1015–1020, 1983.
161. Musacchia, X. J., J. M. Steffen, and R. D. Fell. Disuse atrophy of skeletal muscle: animal models. In: Exercise and Sport Science Reviews, edited by K. B. Pandolf. New York: Macmillan, 1988, vol. 16, p. 61–87.
162. Musacchia, X. J., J. M. Steffen, R. D. Fell, and M. J. Dombrowski. Comparative morphometry of fibers and capillaries in soleus following weightlessness (SL‐3) and suspension. Physiologist 31 (Suppl.): S28–S29, 1988.
163. Musacchia, X. J., J. M. Steffen, R. D. Fell, M. J. Dombrowski, V. W. Oganov, and E. I. Ilyina‐Kakueva. Skeletal muscle atrophy in response to 14 days of weightlessness: vastus medialis. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 44S‐50S, 1992.
165. Oganov, V. S., Results of biosatellite studies of gravity‐dependent changes in the musculo‐skeletal system of mammals. Physiologist 24 (Suppl.): S55–S58, 1981.
166. Oganov, V. S., Neurotrophic influences in the adaptation of skeletal muscles and motor functions to weightlessness. In: Mechanisms of Neural Regulation of Muscle Function, edited by G. A. Nasledov. Leningrad: Nauka, 1988, p. 107–136.
167. Oganov, V. S., V. S. Gurfinkel, V. G. Kozlova, A. S. Rakhmanov, and V. S. Magedov. The effect of prolonged hypokinesia and microgravity on man's skeletal muscles: Use of electromechanical efficiency as a criterion. Piziol. Cheloveka 17: 35–47, 1991.
168. Oganov, V. S., and A. N. Potapov. On the mechanisms of changes in skeletal muscles in the weightless environment. Life Sci. Space Res. 14: 136–143, 1976.
169. Ohira, Y., B. Jiang, R. R. Roy, V. Oganov, E. Ilyina‐Kakueva, J. F. Marini, and V. R. Edgerton. Adaptation of fibers in a slow muscle of rats to spaceflight (Cosmos 2044) and hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 51S–57S, 1992.
170. Overton, J. M., C. R. Woodman, and C. M. Tipton. Effect of hindlimb suspension on Vo2max and regional blood flow responses to exercise. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 66: 653–659, 1989.
171. Paloski, W. H., M. F. Reschke, F. O. Black, D. D. Doxey, and D. L. Harm. Recovery of postural equilibrium control following spaceflight. In: Sensing and Controlling Motion: Vestibular and Sensorimotor function, edited by B. Cohen, D. Tomko, and F. Guedry. Ann. N. Y. Acad. Sci. 656: 747–754, 1992.
172. Peter, J. B., S. Sawaki, R. J. Barnard, V. R. Edgerton, and C. A. Gillespie. Lactate dehydrogenase isoenzymes: Distribution in fast‐twitch red, fast‐twitch white, and slow‐twitch intermediate fibers of guinea pig skeletal muscle. Arch. Biochem. Biophys. 144: 304–307, 1974.
173. Pette, D., and G. Vrbova. Adaptation of mamalian skeletal muscle fibers to chronic electrical stimulation. Rev. Physiol. Biochem. Pharmacol. 120: 115–202, 1992.
174. Pierotti, D. J., R. R. Roy, J. A. Hodgson, and V. R. Edgerton. Level of independence of motor unit properties from neuromuscular activity. Muscle Nerve 17: 1324–1335, 1994.
175. Pierotti, D. J., R. R. Roy, S. C. Bodine‐Fowler, J. A. Hodgson, and V. R. Edgerton. Mechanical and morphological properties of chronically inactive cat tibialis anterior motor units. J. Physiol. (Lond) 444: 175–192, 1991.
176. Pierotti, D. J., R. R. Roy, V. Flores, and V. R. Edgerton. Influence of 7 days of hindlimb suspension and intermittent weight support on rat muscle mechanical properties. Aviat. Space Environ. Med. 61: 205–210, 1990.
177. Pierotti, D. J., R. R. Roy, R. J. Gregor, and V. R. Edgerton. Electromyographic activity of cat hindlimb flexors and extensors during locomotion at varying speeds and inclines. Brain Res. 481: 57–66, 1989.
178. Polyakov, I. V., V. I. Drobyshev, and I. B. Krasnov. Morphological changes in the spinal cord and intervertebral ganglia of rats exposed to different gravity levels. Physiologist 34 (Suppl. 1): S187–S188, 1991.
179. Portugalov, V. V., and N. V. Petrova. LDH isoenzymes of skeletal muscles of rats after space flight and hypokinesia. Aviat. Space Environ. Med. 47: 834–838, 1976.
180. Rapcsak, M., V. S. Oganov, L. M. Murashko, T. Szilagyi, and A. Szoor. Effect of short‐term spaceflight on the contractile properties of rat skeletal muscles with different functions. Acta Physiol. Hung. 76: 13–20, 1990.
181. Reiser, P. J., C. E. Kasper, and R. L. Moss. Myosin subunits and contractile properties of single fibers from hypokinetic rat muscles. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 2293–2300, 1987.
182. Reiser, P. J., R. L. Moss, G. G. Giulian, and M. L. Greaser. Shortening velocity in single fibers from adult rabbit soleus muscles is correlated with myosin heavy chain composition. J. Biol. Chem. 260: 9077–9080, 1985.
183. Reschke, M. F., D. J. Anderson, and J. L. Homick. Vestibulospinal reflexes as a function of microgravity. Science 225: 212–214, 1984.
184. Reschke, M. F., D. J. Anderson, and J. L. Homick. Vestibulospinal response modification as determined with the H‐reflex during the Spacelab‐1 flight. Exp. Brain Res. 64: 367–379, 1986.
185. Riley, D. A., S. Ellis, C. S. Giometti, J. F. Y. Hoh, E. I. Ilyina‐Kakueva, V. S. Oganov, G. R. Slocum, J. L. W. Bain, and F. R. Sedlak. Muscle sarcomere lesions and thrombosis after spaceflight and suspension unloading. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 33S–43S, 1992.
186. Riley, D. A., S. Ellis, G. R. Slocum, T. Satyanarayana, J. L. W. Bain, and F. R. Sedlak. Hypogravity‐induced atrophy of rat soleus and extensor digitorum longus muscles. Muscle Nerve 10: 560–568, 1987.
187. Riley, D. A., E. I. Ilyina‐Kakueva, S. Ellis, J. L. W. Bain, G. R. Slocum, and F. R. Sedlak. Skeletal muscle fiber, nerve, and blood vessel breakdown in space‐flown rats. FASEB J. 4: 84–91, 1990.
188. Riley, D. A., G. R. Slocum, J. L. W. Bain, F. R. Sedlak, T. E. Sowa, and J. W. Mellender. Rat hindlimb unloading: soleus histochemistry, ultrastructure, and electromyography. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 69: 58–66, 1990.
189. Rios, E., and G. Brum. Involvement of dihydropyridine receptors in excitation‐contraction coupling in skeletal muscle. Nature 325: 717–720, 1987.
190. Roy, R. R., K. M. Baldwin, and V. R. Edgerton. The plasticity of skeletal muscle: Effects of neuromuscular activity. In: Exercise and Sports Sciences Reviews, edited by J. Holloszy. Baltimore, MD: Williams and Wilkins, 1991, vol. 19, p. 269–312.
191. Roy, R. R., M. A. Bello, P. Boissou, and V. R. Edgerton. Size and metabolic properties of fibers in fast‐twitch muscles after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 62: 2348–2357, 1987.
192. Roy, R. R., R. E. Grindeland, E. Grossman, V. Mukku, R. Talmadge, and V. R. Edgerton. Growth hormone, insulin‐like growth factor‐1 and exercise interactions in maintaining muscle mass during hindlimb suspension of hypophysectomized rats. ASGSB Bull. 6: 94, 1992.
193. Roy, R. R., J. A. Hodgson, G. R. Chalmers, W. Buxton, and V. R. Edgerton. Responsiveness of the cat plantaris to functional overload. In: Medicine and Sports Science: Integration of Medical and Sport Sciences, edited by Y. Sato, J. Poortmans, I. Hashimoto, and Y. Oshida. Basel: Karger, 1992, vol. 37, p. 43–51.
194. Roy, R. R., D. L. Hutchison, J. A. Hodgson, and V. R. Edgerton. EMG amplitude patterns in rat soleus and medial gastrocnemius following seven days of hindlimb suspension. IEEE Trans. Biomed. Eng. 10: 1710–1711, 1988.
195. Roy, R. R., D. J. Pierotti, V. Flores, W. Rudolph, and V. R. Edgerton. Fibre size and type adaptations to spinal isolation and cyclical passive stretch in cat hindlimb. J. Anat. 180: 491–499, 1992.
196. Roy, R. R., R. D. Sacks, K. M. Baldwin, M. Short, and V. R. Edgerton. Interrelationships of contraction time, Vmax and myosin ATPase after spinal transection. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 56: 1594–1601, 1984.
197. Salmons, S., and J. Henriksson. The adaptive response of skeletal muscle to increased use. Muscle Nerve 4: 94–105, 1981.
198. Salmons, S., and G. Vrbova. The influence of activity on some contractile characteristics of mammalian fast and slow muscles. J. Physiol. (Lond) 201: 535–549, 1969.
199. Saltin, B., and P. D. Gollnick. Skeletal muscle adaptability: Significance for metabolism and performance. In: Handbook of Physiology. Skeletal Muscle, edited by L. D. Peachey. Bethesda, MD: Am. Physiol. Soc., 1983, sect. 10, chapt. 19, p. 555–631.
200. Sancesario, G., R. Massa, A. Anzil, and G. Bernardi. Active muscle length reduction progressively damages soleus in hindlimb‐suspended rabbits. Muscle Nerve 15: 1002–1015, 1992.
201. Schmidt, H. H., and D. J. Reid. Anecdotal information on space adaptation syndrome. NASA/Space Biomedical Research Institute and USRA/Division of Space Biomedicine, July, 1–21, 1985.
202. Shaw, S. R., R. F. Zernicke, A. C. Vailas, D. Deluna, D. B. Thomason, and K. M. Baldwin. Mechanical, morphological and biochemical adaptations of bone and muscle to hindlimb suspension and exercise. J. Biomech. 20: 225–234, 1987.
203. Simard, C., and M. Lacaille. Contractile and histochemical properties of young and old medial gastrocnemius muscle after suspension hypokinesia/hypodynamia. Mech. Ageing Dev. 44: 103–114, 1988.
204. Simard, C., M. Lacaille, and J. Vallieres. Enzymatic adaptations to suspension hypokinesia in skeletal muscle of young and old rats. Mech. Ageing Dev. 33: 1–9, 1985.
205. Spector, S. A., C. P. Simard, M. Fournier, E. Sternlicht, and V. R. Edgerton. Architectural alterations of rat hindlimb skeletal muscles immobilized at different lengths. Exp. Neurol. 76: 94–110, 1982.
206. Steffen, J. M, R. D. Fell, T. E. Geoghegan, L. C. Ringel, and X. J. Musacchia. Age effects on rat hindlimb muscle atrophy during suspension unloading. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 927–931, 1990.
207. Steffen, J. M., and X. J. Musacchia. Effect of hypokinesia and hypodynamia on protein, RNA, and DNA in rat hindlimb muscles. Am. J. Physiol. 247 (Regulatory Integrative Comp. Physiol. 18): R728–R732, 1984.
208. Steffen, J. M., and X. J. Musacchia. Spaceflight effects on adult rat muscle protein, nucleic acids and amino acids. Am. J. Physiol. 251 (Regulatory Integrative Comp. Physiol. 22): R1059–R1063, 1986.
209. Steffen, J. M., R. Robb, M. J. Dombrowski, X. J. Musacchia, A. D. Mandel, and G. Sonnenfeld. A suspension model for hypokinetic/hypodynamic and antiorthostatic responses in the mouse. Aviat. Space Environ. Med. 55: 612–616, 1984.
210. Stevens, L., and Y. Mounier. Ca2+ movements in sarcoplasmic reticulum of rat soleus fibers after hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 72: 1735–1740, 1992.
211. Stevens, L., Y. Mounier, X. Holy, and M. Falempin. Contractile properties of rat soleus muscle after 15 days of hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 334–340, 1990.
212. Stump, C. S., T. W. Balon, and C. M. Tipton. Effects of insulin and exercise on rat hindlimb muscles after simulated microgravity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73: 2044–2053, 1992.
213. Stump, C. S., J. M. Overton, and C. M. Tipton. Influence of single hindlimb support during simulated weightlessness in the rat. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 627–634, 1990.
214. Sweeney, H. L., M. J. Kushmerick, K. Mabuchi, F. A. Sreter, and J. Gergely. Myosin alkali light chain and heavy chain correlate with altered shortening velocity of isolated skeletal muscle fibers. J. Biol. Chem. 263: 9034–9039, 1988.
215. Taguchi, S., H. Morii, and A. Ishihara. Effects of body suspension on soleus muscle fibres and spinal motoneurons in the rat. Comp. Biochem. Physiol. 100A: 801–803, 1991.
216. Takahashi, H., M. Wada, and S. Katsuta. Expressions of myosin heavy chain IId isoform in rat soleus muscle during hindlimb suspension. Acta Physiol. Scand. 143: 131–132, 1991.
217. Templeton, G. H., M. Padalino, J. Manton, M. Glasberg, C. J. Silver, P. Silver, G. DeMartino, T. Leconey, G. Klug, H. Hagler, and J. L. Sutko. Influence of suspension hypokinesia on rat soleus muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 56: 278–286, 1984.
218. Templeton, G. H., M. Padalino, J. Manton, T. Leconey, H. Hagler, and M. Glasberg. The influence of rat suspension‐hypokinesia on the gastrocnemius muscle. Aviat. Space Environ. Med. 55: 381–386, 1984.
219. Templeton, G. H., L. Sweeney, B. F. Timson, M. Padalino, and G. A. Dudenhoefter. Changes in fiber composition of soleus muscle during rat hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 1191–1195, 1988.
220. Thomason, D. B., K. M. Baldwin, and R. E. Herrick. Myosin isozyme distribution in rodent hindlimb skeletal muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 60: 1923–1931, 1986.
221. Thomason, D. B., R. B. Biggs and F. W. Booth. Protein metabolism and β‐myosin heavy‐chain mRNA in unweighted soleus muscle. Am. J. Physiol. 257 (Regulatory Integrative Comp. Physiol. 28): R300–R305, 1989.
222. Thomason, D. B., and F. W. Booth. Atrophy of the soleus muscle by hindlimb unweighting. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 68: 1–12, 1990.
223. Thomason, D. B., R. E. Herrick, and K. M. Baldwin. Activity influences on soleus muscle myosin during rodent hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 138–144, 1987.
224. Thomason, D. B., R. E. Herrick, D. Surdyka, and K. M. Baldwin. Time course of soleus muscle myosin expression during hindlimb suspension and recovery. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 130–137, 1987.
225. Thomason, D. B., P. R. Morrison, V. Oganov, E. Ilyina‐Kakueva, F. W. Booth, and K. M. Baldwin. Altered actin and myosin expression in muscle during exposure to microgravity. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73 (Suppl.): 90S–93S, 1992.
226. Tidball, J. G., and D. M. Quan. Reduction in myotendinous junction surface area of rats subjected to 4–day spaceflight. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 73: 59–64, 1992.
227. Tower, S. S., Function and structure in the chronically isolated lumbosacral spinal cord of the dog. J. Comp. Neurol. 67: 109–127, 1937.
228. Tseng, B. S., C. E. Kasper, and V. R. Edgerton. Cytoplasm‐to‐myonucleus ratios and succinate dehydrogenase activities in adult rat slow and fast muscle fibers. Cell Tiss. Res. 275: 39–49, 1994.
229. Tsika, R. W., R. E. Herrick, and K. M. Baldwin. Interaction of compensatory overload and hindlimb suspension on myosin isoform expression. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 62: 2180–2186, 1987.
230. Tsika, R. W., R. E. Herrick, and K. M. Baldwin. Subunit composition of rodent isomyosins and their distribution in hindlimb skeletal muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 2101–2110, 1987.
231. Tsika, R. W., R. E. Herrick, and K. M. Baldwin. Time course of adaptations in rat skeletal muscle isomyosins during compensatory growth and regression. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 2111–2121, 1987.
232. Tsika, R. W., R. E. Herrick, and K. M. Baldwin. Effect of anabolic steroids on skeletal muscle mass during hindlimb suspension. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 2122–2127, 1987.
233. Tsika, R. W., R. E. Herrick, and K. M. Baldwin. Effect of anabolic steroids on overloaded and overloaded suspended skeletal muscle. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 63: 2128–2133, 1987.
234. Ushakov, A. S., T. F. Vlasova, and E. B. Miroshnikova. Studies of amino acid metabolism in the muscles of rats flown aboard the biosatellite COSMOS 782. In: Proceedings of the Symposium on Gravitational Physiology. Oxford: Permagon, 1979, p. 231–234.
235. Watt, D. G. D., K. E. Money, R. L. Bondar, R. B. Thirsk, M. Garneau, and P. Scully‐Power. Canadian medical experiments on shuttle flight 41G. Can. Aeronaut. Space J. 31: 216–226, 1985.
236. Watt, D. G. D., K. E. Money, and L. M. Tomi. M.I.T./Canadian vestibular experiments on the Spacelab‐1 mission. 3. Effects of prolonged weightlessness on a human otolithspinal reflex. Exp. Brain Res. 64: 308–315, 1986.
237. Winiarski, A. M., R. R. Roy, E. K. Alford, P. C. Chiang, and V. R. Edgerton. Mechanical properties of rat skeletal muscle after hindlimb suspension. Exp. Neurol. 96: 650–660, 1987.
238. Wong, T. S., and F. W. Booth. Skeletal muscle enlargement with weight‐lifting exercise by rats. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 65: 950–954, 1988.
239. Wong, T. S., and F. W. Booth. Protein metabolism in rat tibialis anterior muscle after stimulated chronic eccentric exercise. J. Appl. Physiol.: Respir. Environ. Exerc. Physiol. 69: 1718–1724, 1990.
240. Young, L. R., D. K. Jackson, N. Groleau, and S. Modestino. Multisensory integration in microgravity. In: Sensing and Controlling Motion: Vestibular and Sensorimotor Function, edited by B. Cohen, D. Tomko, and F. Guedry. Ann. N. Y. Acad. Sci., 656: 340–353, 1992.
241. Young, L. R., C. M. Oman, D. G. D. Watt, K. E. Money, and B. K. Lichtenberg. Spatial orientation in weightlessness and readaptation to Earth's gravity. Science 225: 205–208, 1984.
242. Zhou, M. Y., H. Klitgaard, B. Saltin, R. R. Roy, V. R. Edgerton, and P. D. Gollnick. Myosin heavy chain isoform of human muscle after short‐term spaceflight. J. Appl. Physiol. 78: 1740–1744, 1995.

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