An exploration of the association between frailty and muscle fatigue

Applied Physiology, Nutrition and Metabolism

Volumn 33, Issue 4, 2008, Pages 651-665

  Theou, Olga ^a   Jones, Gareth R ^b   Overend, Tom J ^a   Kloseck, Marita ^a   Vandervoort, Anthony A ^a  

^a UNIVERSITY OF WESTERN ONTARIO   (Canada)

^b UNIVERSITY OF BRITISH COLUMBIA   (Canada)

Author keywords

Aging; Exercise intolerance; Frailty; Muscle fatigue; Physical activity; Sarcopenia

Indexed keywords

AGED; AGING; FRAIL ELDERLY; GAIT; HUMAN; MOTOR ACTIVITY; MUSCLE FATIGUE; MUSCLE WEAKNESS; PATHOPHYSIOLOGY; PHYSIOLOGY; REVIEW;

AGED; AGED, 80 AND OVER; AGING; FRAIL ELDERLY; GAIT; HUMANS; MOTOR ACTIVITY; MUSCLE FATIGUE; MUSCLE WEAKNESS;

EID: 48649103745     PISSN: 17155312     EISSN: None     Source Type: Journal    
DOI: 10.1139/H08-058     Document Type: Review

References (157)

1. Abbiss, C.R., and Laursen, P.B. 2005. Models to explain fatigue during prolonged endurance cycling. Sports Med. 35: 865-898. doi:10.2165/00007256-200535100-00004. PMID:16180946.
2. Allaire, J., Maltais, F., Doyon, J.-F., Noel, M., LeBlanc, P., Carrier, G., et al. 2004. Peripheral muscle endurance and the oxidative profile of the quadriceps in patients with COPD. Thorax, 59: 673-678. doi:10.1136/thx.2003.020636. PMID:15282387.
3. Allman, B.L., and Rice, C.L. 2001. Incomplete recovery of voluntary isometric force after fatigue is not affected by old age. Muscle Nerve, 24: 1156-1167. doi:10.1002/mus.1127. PMID:11494268.
4. Allman, B.L., and Rice, C.L. 2002. Neuromuscular fatigue and aging: central and peripheral factors. Muscle Nerve, 25: 785-796. doi:10.1002/mus.10116. PMID:12115966.
5. Allman, B.L., and Rice, C.L. 2004. An age-related shift in the force-frequency relationship affects quadriceps fatigability in old adults. J. Appl. Physiol. 96: 1026-1032. PMID:14594856.
6. Avlund, K., Rantanen, T., and Schroll, M. 2007. Factors underlying tiredness in older adults. Aging Clin. Exp. Res. 19: 16-25. PMID:17332717.
7. Bandeen-Roche, K., Xue, Q.-L., Ferruci, L., Walston, J., Guralnik, J.M., Chaves, P., et al. 2006. Phenotype of frailty: characterization in the women's health and aging studies. J. Gerontol. A Biol. Sci. Med. Sci. 61: 262-266. PMID:16567375.
8. Bartali, B., Frongillo, E.A., Bandinelli, S., Lauretani, F., Semba, R.D., Fried, L.P., et al. 2006. Low nutrient intake is an essential component of frailty in older persons. J. Gerontol. A Biol. Sci. Med. Sci. 61: 589-593. PMID:16799141.
9. Bautmans, I., Gorus, E., Njemini, R., and Mets, T. 2007. Handgrip performance in relation to self-perceived fatigue, physical functioning and circulating IL-6 in elderly persons without inflammation. BMC Geriatr. 7:5. doi:10.1186/1471-2318-7-5.
10. Bautmans, I., and Mets, T. 2005. A fatigue resistance test for elderly persons based on grip strength: reliability and comparison with healthy young subjects. Aging Clin. Exp. Res. 17: 217-222. PMID:16110735.
11. Bergman, H., Béland, F., Karunanathan, S., Hummel, S., Hogan, D., and Wolfson, C. 2004. Developing a working framework for understanding frailty. Gerontol. Soc. 109: 15-29.
12. Bermon, S., Venembre, P., Sachet, C., Valour, S., and Dolisi, C. 1998. Effects of creatine monohydrate ingestion in sedentary and weight-trained older adults. Acta Physiol. Scand. 164: 147-155. doi:10.1046/j.1365-201X.1998. 00427.x. PMID:9805101.
13. Bischoff, H.A., Stahelin, H.B., Urscheler, N., Ehrsam, R., Vonthein, R., Perrig-Chiello, P., et al. 1999. Muscle strength in the elderly: its relation to vitamin D metabolites. Arch. Phys. Med. Rehabil. 80: 54-58. doi:10.1016/S0003-9993(99)90307-6. PMID:9915372.
14. Blaum, C.S., Xue, Q.-L., Michelon, E., Semba, R.D., and Fried, L.P. 2005. The association between obesity and the frailty syndrome in older women: the women's health and aging studies. J. Am. Geriatr. Soc. 53: 927-934. doi:10.1111/j.1532-5415.2005. 53300.x. PMID:15935013.
15. Bortz, W.M. 2002. A conceptual framework of frailty: a review. J. Gerontol. A Biol. Sci. Med. Sci. 57: 283-288.
16. Bouzubar, F.F. 2003. Self-reported fatigue in individuals with knee osteoarthritis. Ph.D. thesis, University of Pittsburgh, Pittsburgh, Pa.
17. Borg, G. 1998. Borg's perceived exertion and pain scales. Human Kinetics, Champaign, Ill.
18. Boyd, C.M., Xue, Q.-L., Simpson, C.F., Guralnik, J.M., and Fried, L.P. 2005. Frailty, hospitalization, and progression of disability in a cohort of disabled older women. Am. J. Med. 118: 1225-1231. doi:10.1016/j.amjmed. 2005.01.062. PMID:16271906.
19. Brassard, P., Maltais, F., Noel, M., Doyon, J.-F., LeBlanc, P., Allaire, J., et al. 2006. Skeletal muscle endurance and muscle metabolism in patients with chronic heart failure. Can. J. Cardiol. 22: 387-392. PMID:16639473.
20. Cappola, A.R., Bandeen-Roche, K., Wand, G.S., Volpato, S., and Fried, L.P. 2001. Association of IGF-I levels with muscle strength and mobility in older women. J. Clin. Endocrinol. Metab. 86: 4139-4146. doi:10.1210/jc.86.9.4139. PMID:11549640.
21. Cesari, M., Leeuwenburgh, C., Lauretani, F., Onder, G., Bandinelli, S., Maraldi, C., et al. 2006. Frailty syndrome and skeletal muscle: results from the Invecchiare in Chianti study. Am. J. Clin. Nutr. 83: 1142-1148. PMID:16685058.
22. Chahal, H.S., and Drake, W.M. 2007. The endocrine system and ageing. J. Pathol. 211: 173-180. doi:10.1002/path.2110. PMID:17200939.
23. Chan, K.M., Raja, A.J., Strohschein, F.J., and Lechelt, K. 2000. Age-related changes in muscle fatigue resistance in humans. Can. J. Neurol. Sci. 27: 220-228. PMID:10975534.
24. Chandler, J.M., Duncan, P.W., Kochersberger, G., and Studenski, S. 1998. Is lower extremity strength gain associated with improvement in physical performance and disability in frail, community-dwelling elders? Arch. Phys. Med. Rehabil. 79: 24-30. doi:10.1016/S0003-9993(98)90202-7. PMID:9440412.
25. Cheng, A., Ditor, D.S., and Hicks, A.L. 2003. A comparison of adductor pollicis fatigue in older men and women. Can. J. Physiol. Pharmacol. 81: 873-879. doi:10.1139/y03-084. PMID:14614523.
26. Chrusch, M.J., Chilibeck, P.D., Chad, K.E., Shawn, D.K., and Burke, D.G. 2001. Creatine supplementation combined with resistance training in older men. Med. Sci. Sports Exerc. 33: 2111-2117. PMID:11740307.
27. Coggan, A.R., Abduljalil, A.M., Swanson, S.C., Earle, M.S., Farris, J.W., Mendenhall, L.A., et al. 1993. Muscle metabolism during exercise in young and older untrained and endurance-trained men. J. Appl. Physiol. 75: 2125-2133. PMID:8307869.
28. Copeland, J.L., Chu, S.Y., and Tremblay, M.S. 2004. Aging, physical activity, and hormones in women - a review. J. Aging Phys. Act. 11: 101-116.
29. Cress, M.E., and Meyer, M. 2003. Maximal voluntary and functional performance levels needed for independence in adults aged 65 to 97 years. Phys. Ther. 83: 37-48. PMID:12495411.
30. Cupido, C.M., Hicks, A.L., and Martin, J. 1992. Neuromuscular fatigue during repetitive stimulation in elderly and young adults. Eur. J. Appl. Physiol. 65: 567-572. doi:10.1007/BF00602367.
31. 2 uptake kinetics and muscle deoxygenation at the onset of heavy-intensity exercise in young and older adults. J. Appl. Physiol. 98: 1697-1704. doi:10.1152/japplphysiol.00607.2004. PMID:15640394.
32. Ditor, D.S., and Hicks, A.L. 2000. The effect of age and gender on the relative fatigability of the human adductor pollicis muscle. Can. J. Physiol. Pharmacol. 78: 781-790. doi:10.1139/cjpp-78-10-781. PMID:11077978.
33. Doherty, T.J. 2003. Invited review: aging and sarcopenia. J. Appl. Physiol. 95: 1717-1727. PMID:12970377.
34. Doherty, T.J., and Brown, W.F. 1993. The estimated numbers and relative sizes of thenar motor units as selected by multiple point stimulation in young and older adults. Muscle Nerve, 16: 355-366. doi:10.1002/mus.880160404. PMID:8455648.
35. Doherty, T.J., Vandervoort, A.A., and Brown, W.F. 1993a. Effects of ageing on the motor unit: a brief review. Can. J. Appl. Physiol. 18: 331-358. PMID:8275048.
36. Doherty, T.J., Vandervoort, A.A., Taylor, A.W., and Brown, W.F. 1993b. Effects of motor unit losses on strength in older men and women. J. Appl. Physiol. 74: 868-874. PMID:8458808.
37. Dohi, K., Mastro, A.M., Miles, M.P., Bush, J.A., Grove, D.S., Leach, S.K., et al. 2001. Lymphocyte proliferation in response to acute heavy resistance exercise in women: influence of muscle strength and total work. Eur. J. Appl. Physiol. 85: 367-373. doi:10.1007/s004210100388. PMID:11560093.
38. Ensrud, K.E., Ewing, S.K., Taylor, B.C., Fink, H.A., Cawthon, P.M., Stone, K.L., et al. 2008. Comparison of 2 frailty indexes for prediction of falls, disability, fractures, and death in older women. Arch. Intern. Med. 168: 382-389. doi:10.1001/archinternmed.2007.113. PMID:18299493.
39. Evans, W.J. 2004. Protein nutrition, exercise and aging. J. Am. Coll. Nutr. 23: S601-S609.
40. Faber, M.J., Bosscher, R.J., Chin, A., Paw, M.J., and van Wieringen, P.C. 2006. Effects of exercise programs on falls and mobility in frail and pre-frail older adults: a multicenter randomized controlled trial. Arch. Phys. Med. Rehabil. 87: 885-896. doi:10.1016/j.apmr.2006.04.005. PMID:16813773.
41. Ferrucci, L., Guralnik, J.M., Studenski, S., Fried, L.P., Cutler, G.B., and Walston, J.D. 2004. Designing randomized, controlled trials aimed at preventing or delaying functional decline and disability in frail, older persons: a consensus report. J. Am. Geriatr. Soc. 52: 625-634. doi:10.1111/j.1532-5415.2004.52174.x. PMID:15066083.
42. Fiatarone, M.A., O'Neill, E.F., Ryan, N.D., Clements, K.M., Solares, G.R., Nelson, M.E., et al. 1994. Exercise training and nutritional supplementation for physical frailty in very elderly people. N. Engl. J. Med. 330: 1769-1775. doi:10.1056/NEJM199406233302501. PMID:8190152.
43. Fisher, N.M., and Pendergast, D.R. 1997. Reduced muscle function in patients with osteoarthritis. Scand. J. Rehabil. Med. 29: 213-221. PMID:9428055.
44. Fried, L.P., Ferrucci, L., Darer, J., Williamson, J.D., and Anderson, G. 2004. Untangling the concepts of disability, frailty, and comorbidity: implications for improved targeting and care. J. Gerontol. A Biol. Sci. Med. Sci. 59: 255-263. PMID:15031310.
45. Fried, L.P., Tangen, C.M., Walston, J., Newman, A.B., Hirsch, C., Gottdiener, J., et al. 2001. Frailty in older adults: evidence for a phenotype. J. Gerontol. A Biol. Sci. Med. Sci. 56: M146-M156. PMID:11253156.
46. Fried, L.P., and Walston, J. 2003. Frailty and failure to thrive. In Principles of geriatric medicine and gerontology. 5th ed. Edited by W.R. Hazzard, J.P. Blass, and J.B. Halter. McGraw-Hill, New York, N.Y. pp. 1487-1502.
47. Frontera, W.R., Hughes, V.A., Fielding, R.A., Fiatarone, M.A., Evans, W.J., and Roubenoff, R. 2000. Aging of skeletal muscle: a 12-yr longitudinal study. J. Appl. Physiol. 88: 1321-1326. PMID:10749826.
48. Fry, A.C., Bloomer, R.J., Falvo, M.J., Moore, C.A., Schilling, B.K., and Weiss, L.W. 2006. Effect of a liquid multivitamin/mineral supplement on anaerobic exercise performance. Res. Sports Med. 14: 53-64. PMID:16700404.
49. Fukuda, K., Straus, S.E., Hickie, I., Sharpe, M.C., Dobbins, J.G., and Komaroff, A. 1994. The chronic fatigue syndrome: a comprehensive approach to its definition and study. International chronic fatigue syndrome study group. Ann. Intern. Med. 121: 953-959. PMID:7978722.
50. Gill, T.M., Allore, H.G., Holford, T.R., and Guo, Z. 2004. Hospitalization, restricted activity, and the development of disability among older persons. JAMA, 292: 2115-2124. doi:10.1001/jama.292.17.2115. PMID:15523072.
51. Gill, T.M., Gahbauer, E.A., Allore, H.G., and Han, L. 2006. Transitions between frailty states among community-living older persons. Arch. Intern. Med. 166: 418-423. doi:10.1001/.418. PMID:16505261.
52. Gogia, P.P., and Sabbahi, M.A. 1994. Electromyographic analysis of neck muscle fatigue in patients with osteoarthritis of the cervical spine. Spine, 19: 502-506. PMID:8184341.
53. Gotshalk, L.A., Volek, J.S., Staron, R.S., Denegar, C.R., Hagerman, F.C., and Kraemer, W.J. 2002. Creatine supplementation improves muscular performance in older men. Med. Sci. Sports Exerc. 34: 537-543. PMID:11880821.
54. Gruver, A.L., Hudson, L.L., and Sempowski, G.D. 2007. Immunosenescence of ageing. J. Pathol. 211: 144-156. doi:10.1002/path. 2104. PMID:17200946.
55. Hakkinen, K. 1995. Neuromuscular fatigue and recovery in women at different ages during heavy resistance loading. Electromyogr. Clin. Neurophysiol. 35: 403-413. PMID:8549431.
56. Hakkinin, K., Kraemer, W.J., Kallinen, M., Linnamo, V., Pastinen, U., and Newton, R.U. 1996. Bilateral and unilateral neuromuscular function and muscle cross-sectional area in middle-aged and elderly men and women. J. Gerontol. A Biol. Sci. Med. Sci. 51: B21-B29.
57. Hakkinen, K., Kraemer, W.J., and Newton, R.U. 1997. Muscle activation and force production during bilateral and unilateral concentric isometric contractions of the knee extensors in men and women at different ages. Electromyogr. Clin. Neurophysiol. 37: 131-142.
58. Hakkinen, K., Pakarinen, A., Kraemer, W.J., Newton, R.U., and Alen, M. 2000. Basal concentrations and acute responses of serum hormones and strength development during heavy resistance training in middle-aged and elderly men and women. J. Gerontol. A Biol. Sci. Med. Sci. 55: B95-B105. PMID:10737684.
59. Hakkinen, K., Pakarinen, A., Newton, R.U., and Kraemer, W.J. 1998. Acute hormone responses to heavy resistance lower and upper extremity exercise in young versus old men. Eur. J. Appl. Physiol. 77: 312-319. doi:10.1007/s004210050339.
60. Hamerman, D. 1999. Toward an understanding of frailty. Ann. Intern. Med. 130: 945-950. PMID:10375351.
61. Hebert, R., Brayne, C., and Speigelhalter, D. 1997. Incidence of functional decline and improvement in a community-dwelling, very elderly population. Am. J. Epidemiol. 145: 935-944. PMID:9149665.
62. Herrmann, F.R., Osiek, A., Michel, J.-P., and Robine, J.-M. 2005. Frailty judgment by hospital team members: degree of agreement and survival prediction. J. Am. Geriatr. Soc. 53: 916-917. doi:10.1111/j.1532-5415.2005.53278_6. x. PMID:15877583.
63. Hicks, A.L., Kent-Braun, J., and Ditor, D.S. 2001. Sex differences in human skeletal muscle fatigue. Exerc. Sports Sci. Rev. 29: 109-112.
64. Hirsch, C., Anderson, M.L., Newman, A., Kop, W., Jackson, S., Gottdiener, J., et al. 2006. The association of race with frailty: the cardiovascular health study. Ann. Epidemiol. 16: 545-553. doi:10.1016/j.annepidem.2005. 10.003. PMID:16388967.
65. Hogan, D.B., MacKnight, C., and Bergman, H. 2003. Models, definitions and criteria of frailty. Aging Clin. Exp. Res. 15: 1-29. PMID:14580013.
66. Hortobagyi, T., Mizelle, C., Beam, S., and DeVita, P. 2003. Old adults perform activities of daily living near their maximal capabilities. J. Gerontol. A Biol. Sci. Med. Sci. 58: M453-M460. PMID:12730256.
67. Hunter, S.K., Critchlow, A., and Enoka, R.M. 2004. Influence of aging on sex differences in muscle fatigability. J. Appl. Physiol. 97: 1723-1732. doi:10.1152/japplphysiol.00460.2004. PMID:15208285.
68. Hunter, S.K., Critchlow, A., and Enoka, R.M. 2005. Muscle endurance is greater for old men compared with strength-matched young men. J. Appl. Physiol. 99: 890-897. doi:10.1152/japplphysiol.00243.2005. PMID:15879165.
69. Hurley, M.V. 1998. Quadriceps weakness in osteoarthritis. Curr. Opin. Rheumatol. 10: 246-250. doi:10.1097/00002281-199805000-00015. PMID:9608328.
70. Jakobi, J.M., Connelly, D.M., Roos, M.R., Allman, B.L., and Rice, C.L. 1999. Age-related changes of neuromuscular properties in three human limb muscles. In ALCOA Proceedings: Older adults and active living. Edited by A.W. Taylor, N.A. Ecclestone, G.R. Jones, and D.H. Paterson. Canadian Centre for Activity and Aging, London, Ont. pp. 111-121.
71. Jakobi, J.M., Rice, C.L., Curtin, S.V., and Marsh, G.D. 2001. Neuromuscular properties and fatigue in older men following acute creatine supplementation. Eur. J. Appl. Physiol. 84: 321-328. doi:10.1007/ s004210000373. PMID:11374116.
72. Janaudis-Ferreira, T., Wadell, K., Sundelin, G., and Lindstrom, B. 2006. Thigh muscle strength and endurance in patients with COPD compared with healthy controls. Respir. Med. 100: 1451-1457. PMID:16337114.
73. Kamen, G., Sison, S.V., Du, C.C., and Patten, C. 1995. Motor unit discharge behavior in older adults during maximal-effort contraction. J. Appl. Physiol. 79: 1908-1913. PMID:8847252.
74. Katsiaras, A., Newman, A.B., Kriska, A., Brach, J., Krishnaswami, S., Feingold, E., et al. 2005. Skeletal muscle fatigue, strength, and quality in the elderly: the health ABC study. J. Appl. Physiol. 99: 210-216. doi:10.1152/japplphysiol.01276.2004. PMID:15718402.
75. Kent-Braun, J.A., Ng, A.V., Doyle, J.W., and Towse, T.F. 2002. Human skeletal muscle responses vary with age and gender during fatigue due to incremental isometric exercise. J. Appl. Physiol. 93: 1813-1823. PMID:12381770.
76. Kent-Braun, J.A., Sharma, K.R., Weiner, M.W., Massie, B., and Miller, R.G. 1993. Central basis of muscle fatigue in chronic fatigue syndrome. Neurology, 43: 125-131. PMID:8423875.
77. Klein, C., Cunningham, D.A., Paterson, D.H., and Taylor, A.W. 1988. Fatigue and recovery contractile properties of young and elderly men. Eur. J. Appl. Physiol. 57: 684-690. doi:10.1007/BF01075989.
78. Klitgaard, H., Mantoni, M., Schiaffino, S., Ausoni, S., Gorza, L., Laurent-Winter, C., et al. 1990. Function, morphology and protein expression of ageing skeletal muscle: a cross-sectional study of elderly men with different training backgrounds. Acta Physiol. Scand. 140: 41-54. PMID:2275404.
79. Kostka, T., Patricot, M.C., Mathian, B., Lacour, J.-R., and Bonnefoy, M. 2003. Anabolic and catabolic hormonal responses to experimental two-set low-volume resistance exercise in sedentary and active elderly people. Aging Clin. Exp. Res. 15: 123-130. PMID:12889843.
80. 2max in men and women aged more than 65 years. J. Gerontol. A Biol. Sci. Med. Sci. 55: B481-B488. PMID:11034221.
81. Kraemer, W.J., Hakkinen, K., Newton, R.U., McCormick, M., Nindi, B.C., Volek, J.S., et al. 1998. Acute hormonal responses to heavy resistance exercise in younger and older men. J. Appl. Phyfiiol. Occup. Physiol. 77: 206-211.
82. Laforest, S., St-Pierre, D.M., Cyr, J., and Gayton, D. 1990. Effects of age and regular exercise on muscle strength and endurance. Eur. J. Appl. Physiol. 60: 104-111. doi:10.1007/BF00846029.
83. Lambert, C.P., Archer, R.L., and Evans, W.J. 2001. Muscle strength and fatigue during isokinetic exercise in individuals with multiple sclerosis. Med. Sci. Sports Exerc. 33: 1613-1619. PMID:11581542.
84. Lamberts, S.W., van den Beld, A.W., and van der Lely, A.-J. 1997. The endocrinology of aging. Science, 278: 419-424. doi:10.1126/science.278. 5337.419. PMID:9334293.
85. Lanza, I.R., Befroy, D.E., and Kent-Braun, J.A. 2005. Age-related changes in ATP-producing pathways in human skeletal muscle in vivo. J. Appl. Physiol. 99: 1736-1744. doi:10.1152/japplphysiol.00566.2005. PMID:16002769.
86. Lanza, I.R., Russ, D.W., and Kent-Braun, J.A. 2004. Age-related enhancement of fatigue resistance is evident in men during both isometric and dynamic tasks. J. Appl. Physiol. 97: 967-975. doi:10.1152/japplphysiol. 01351.2003. PMID:15145914.
87. Leng, S., Cappola, A.R., Andersen, R.E., Blackman, M.R., Koenig, K., Blair, M., et al. 2004. Serum levels of insulin-like growth factor-I (IGF-I) and dehydroepiandrosterone sulfate (DHEA-S), and their relationships with serum interleukin-6, in the geriatric syndrome of frailty. Aging Clin. Exp. Res. 16: 153-157. PMID:15195991.
88. Leng, S.X., Xue, Q.-L., Tian, J., Walston, J.D., and Fried, L.P. 2007. Inflammation and frailty in older women. J. Am. Geriatr. Soc. 55: 864-871. doi:10.1111/j.1532-5415.2007.01186.x. PMID:17537086.
89. Levers, M.-J., Estabrooks, C.A., and Ross Kerr, J.C. 2006. Factors contributing to frailty: literature review. J. Adv. Nurs. 56: 282-291. doi:10.1111/j.1365-2648.2006.04021.x. PMID:17042807.
90. Lexell, J., and Taylor, C.C. 1991. Variability in muscle fibre areas in whole human quadriceps muscle: effect of increasing age. J. Anat. 174: 239-249. PMID:2032938.
91. Lexell, J., Taylor, C.C., and Sjostrom, M. 1988. What is the cause of the ageing atrophy? Total number, size and proportion of different fiber types studied in whole vastus lateralis muscle from 15- to 83-year-old men. J. Neurol. Sci. 84: 275-294. doi:10.1016/0022-510X(88)90132-3. PMID:3379447.
92. Lips, P. 2001. Vitamin D deficiency and secondary hyperparathyroidism in the elderly: consequences for bone loss and fractures and therapeutic implications. Endocr. Rev. 22: 477-501. doi:10.1210/er.22.4.477. PMID:11493580.
93. Macaluso, A., and De Vito, G. 2004. Muscle strength, power and adaptations to resistance training in older people. Eur. J. Appl. Physiol. 91: 450-472. doi:10.1007/s00421-003-0991-3. PMID:14639481.
94. Mador, M.J., Bozkanat, E., and Kufel, T.J. 2003. Quadriceps fatigue after cycle exercise in patients with COPD compared with healthy control subjects. Chest, 123: 1104-1111. doi:10.1378/chest.123.4.1104. PMID:12684300.
95. Maquet, D., Croisier, J.-L., Renard, C., and Crielaard, J.-M. 2002. Muscle performance in patients with fibromyalgia. Joint Bone Spine, 69: 293-299. doi:10.1016/S1297-319X(02)00373-1. PMID:12102276.
96. Markle-Reid, M., and Browne, G. 2003. Conceptualization of frailty in relation to older adults. J. Adv. Nurs. 44: 58-68. doi:10.1046/j.1365- 2648.2003.02767.x. PMID:12956670.
97. McNeil, C.J., and Rice, C.L. 2007. Fatigability is increased with age during velocity-dependent contractions of the dorsiflexors. J. Gerontol. A Biol. Sci. Med. Sci. 62: 624-629.
98. Meeusen, R., Watson, P., Hasegawa, H., Roelands, B., and Piacentini, M.F. 2006. Central fatigue. The serotonin hypothesis and beyond. Sports Med. 36: 881-909. doi:10.2165/00007256-200636100-00006. PMID:17004850.
99. Melton, L.J., Khosla, S., Crowson, C.S., O'Connor, M.K., O'Fallon, W.M., and Riggs, B.L. 2000. Epidemiology of sarcopenia. J. Am. Geriatr. Soc. 48: 625-630. PMID:10855597.
100. Mets, T., Bautmans, I., Njemini, R., Lambert, M., and Demanet, C. 2004. The influence of celecoxib on muscle fatigue resistance and mobility in elderly patients with inflammation. Am. J. Geriatr. Pharmacother. 2: 230-238. doi:10.1016/j.amjopharm.2004.12.007. PMID:15903281.
101. Michelon, E., Blaum, C., Semba, R.D., Xue, Q.-L., Ricks, M.O., and Fried, L.P. 2006. Vitamin and carotenoid status in older women: associations with the frailty syndrome. J. Gerontol. A Biol. Sci. Med. Sci. 61: 600-607. PMID:16799143.
102. Miller, R.G. 2002. Role of fatigue in limiting physical activities in humans with neuromuscular diseases. Am. J. Phys. Med. Rehabil. 81: S99-S107. doi:10.1097/00002060-200211001-00011. PMID:12409815.
103. Monemi, M., Eriksson, P.-O., Eriksson, A., and Thornell, L.-E. 1998. Adverse changes in fibre type composition of the human masseter versus biceps brachii muscle during aging. J. Neurol. Sci. 154: 35-48. doi:10.1016/S0022-510X(97)00208-6. PMID:9543320.
104. National Advisory Council on Aging. 2006. Seniors in Canada 2006 report card. Ottawa, Ont.
105. Nybo, L. 2003. CNS fatigue and prolonged exercise: effect of glucose supplementation. Med. Sci. Sports Exerc. 35: 589-594. doi:10.1249/01.MSS.0000058433.85789.66. PMID:12673141.
106. Nybo, L., and Rasmussen, P. 2007. Inadequate cerebral oxygen delivery and central fatigue during strenuous exercise. Exerc. Sports Sci. Rev. 35: 110-118.
107. Nybo, L., and Secher, N.H. 2004. Cerebral perturbations provoked by prolonged exercise. Prog. Neurobiol. 72: 223-261. doi:10.1016/j. pneurobio.2004.03.005. PMID:15142684.
108. Ottenbacher, K.J., Ostir, G.V., Peek, M.K., Snih, S.A., Raji, M.A., and Makrides, K.S. 2005. Frailty in older Mexican Americans. J. Am. Geriatr. Soc. 53: 1524-1531. doi:10.1111/j.1532-5415.2005.53511.x. PMID:16137282.
109. Overend, T.J., Cunningham, D.A., Kramer, J.F., Lefcoe, M.S., and Paterson, D.H. 1992. Knee extensor and knee flexor strength:-cross-sectional area ratios in young and elderly men. J. Gerontol. 47: M204-M210. PMID:1430855.
110. Petrella, J.K., Kim, J., Tuggle, S.C., Hall, S.R., and Bamman, M.M. 2005. Age differences in knee extension power, contractile velocity, and fatigability. J. Appl. Physiol. 98: 211-220. PMID:15347625.
111. Porter, M.M., Vandervoort, A.A., and Lexell, J. 1995. Aging of human muscle: structure, function and adaptability. Scand. J. Med. Sci. Sports, 5: 129-142. PMID:7552755.
112. 2 during peak cycle exercise in younger and older women. Med. Sci. Sports Exerc. 36: 623-631. doi:10.1249/01.MSS.0000121951.10417.B5. PMID:15064590.
113. Puts, M.T.E., Visser, M., Twisk, J.W.R., Deeg, D.J.H., and Lips, P. 2005. Endocrine and inflammatory markers as predictors of frailty. Clin. Endocrinol. (Oxf.), 63: 403-411. doi:10.1111/j.1365-2265.2005.02355.x. PMID:16181232.
114. Pyka, G., Wiswell, R.A., and Markus, R. 1992. Age-dependent effect of resistance exercise on growth hormone secretion in people. J. Clin. Endocrinol. Metab. 75: 404-407. doi:10.1210/jc.75.2.404. PMID:1639942.
115. Ratel, S., Duche, P., and Williams, C.A. 2006. Muscle fatigue during high-intensity exercise in children. Sports Med. 36: 1031-1065. doi:10.2165/00007256-200636120-00004. PMID:17123327.
116. Rockwood, K., Song, X., MacKnight, C., Bergman, H., Hogan, D.B., McDowell, I., et al. 2005. A global clinical measure of fitness and frailty in elderly people. CMAJ, 173: 489-495. PMID:16129869.
117. Roos, M.R., Rice, C.L., Connelly, D.M., and Vandervoort, A.A. 1999. Quadriceps muscle strength, contractile properties, and motor unit firing rates in young and old men. Muscle Nerve, 22: 1094-1103. doi:10.1002/(SICI) 1097-4598(199908)22:8〈1094::AID-MUS14〉 3.0.CO;2-G. PMID:10417793.
118. Roos, M.R., Rice, C.L., and Vandervoort, A.A. 1997. Age-related changes in motor unit function. Muscle Nerve, 20: 679-690. doi:10.1002/(SICI) 1097-4598(199706)20:6〈679::AID-MUS4〉3.0.CO;2-5. PMID:9149074.
119. Rose, M.R., Sharief, M.K., Priddin, J., Nikolaou, V., Hull, L., Unwin, C., et al. 2004. Evaluation of neuromuscular symptoms in UK Gulf War veterans: a controlled study. Neurology, 63: 1681-1687. PMID:15534255.
120. Saey, D., Cote, C.H., Mador, J., Laviolette, L., Leblanc, P., Jobin, J., et al. 2006. Assessment of muscle fatigue during exercise in chronic obstructive pulmonary disease. Muscle Nerve, 34: 62-71. doi:10.1002/mus.20541. PMID:16583366.
121. Sargeant, A.J. 1994. Human power output and muscle fatigue. Int. J. Sports Med. 15: 116-121. PMID:8005722.
122. Schillings, M.L., Kalkman, J.S., Janssen, H.M.H.A., van Engelen, B.G.M., Bleijenberg, G., and Zwarts, M.J. 2007. Experienced and physiological fatigue in neuromuscular disorders. Clin. Neurophysiol. 118: 292-300. doi:10.1016/j.clinph.2006.10.018. PMID:17166763.
123. Schillings, M.L., Kalkman, J.S., van der Werf, S.P., van Engelen, B.G.M., Bleijenberg, G., and Zwarts, M.J. 2004. Diminished central activation during maximal voluntary contraction in chronic fatigue syndrome. Clin. Neurophysiol. 115: 2518-2524. doi:10.1016/j.clinph.2004.06.007. PMID:15465441.
124. Schmaltz, H.N., Fried, L.P., Xue, Q.-L., Walston, J., Leng, S.X., and Semba, R.D. 2005. Chronic cytomegalovirus infection and inflammation are associated with prevalent frailty in community-dwelling older women. J. Am. Geriatr. Soc. 53: 747-754. doi:10.1111/j.1532-5415.2005.53250.x. PMID:15877548.
125. Schulze, P.C., Linke, A., Schoene, N., Winkler, S.M., Adams, V., Conradi, S., et al. 2004. Functional and morphological skeletal muscle abnormalities correlate with reduced electromyographic activity in chronic heart failure. Eur. J. Cardiovasc. Prev. Rehabil. 11: 155-161. doi:10.1097/01.hjr. 0000124327.85096.a5. PMID:15187820.
126. Schwendner, K.I., Mikesky, A.E., Holt, H.S., Jr., Peacock, M., and Burr, D.B. 1997. Differences in muscle endurance and recovery between fallers and non fallers, and between young and older women. J. Gerontol. A Biol. Sci. Med. Sci. 52: M155-M160. PMID:9158557.
127. Seghers, J., Spaepen, A., Delecluse, C., and Colman, V. 2003. Habitual level of physical activity and muscle fatigue of the elbow flexor muscles in older men. Eur. J. Appl. Physiol. 89: 427-434. doi:10.1007/s00421-003- 0817-3. PMID:12684808.
128. Semba, R.D., Blaum, C.S., Bartali, B., Xue, Q.-L., Ricks, M.O., Guralnik, J.M., et al. 2006. Denture use, malnutrition, frailty, and mortality among older women living in the community. J. Nutr. Health Aging, 10: 161-167. PMID:16554954.
129. Short, K.R., and Nair, K.S. 1999. Mechanisms of sarcopenia of aging. J. Endocrinol. Invest. 22: 95-105. PMID:10442578.
130. Simoneau, E., Martin, A., and Van Hoecke, J. 2005. Muscular performances at the ankle joint in young and elderly men. J. Gerontol. A Biol. Sci. Med. Sci. 60: 439-447. PMID:15933381.
131. Singh, M.A., Ding, W., Manfredi, T.J., Solares, G.S., O'Neill, E.F., Clements, K.M., et al. 1999. Insulin-like growth factor I in skeletal muscle after weight-lifting exercise in frail elders. Am. J. Physiol. 277: 135-143.
132. Smolander, J., Aminoff, T., Korhonen, I., Tevro, M., Shen, N., Korhonen, O., et al. 1998. Heart rate and blood pressure responses to isometric exercise in young and older men. Eur. J. Appl. Physiol. Occup. Physiol. 77: 439-444. doi:10.1007/s004210050357. PMID:9562295.
133. Soltow, Q.A., Betters, J.L., Sellman, J.E., Lira, V.A., Long, J.H.D., and Criswell, D.S. 2006. Ibuprofen inhibits skeletal muscle hypertrophy in rats. Med. Sci. Sports Exerc. 38: 840-846. PMID:16672835.
134. St Clair Gibson, A., Baden, D.A., Lambert, M.I., Lambert, E.V., Harley, Y.X.R., Hampson, D., et al. 2003. The conscious perception of the sensation of fatigue. Sports Med. 33: 167-176. doi:10.2165/00007256-200333030-00001. PMID:12656638.
135. Statistics Canada. 2006. Population and dwelling count: a portrait of the Canadian population. Statistics Canada Catalogue no. 97-550-XWE2006001. Ottawa, Ont.
136. Storer, T.W., Magliano, L., Woodhouse, L., Lee, M.L., Dzekov, C., Dzekov, J., et al. 2003. Testosterone dose-dependently increases maximal voluntary strength and leg power, but does not affect fatigability or specific tension. J. Clin. Endocrinol. Metab. 88: 1478-1485. doi:10.1210/jc.2002-021231. PMID:12679426.
137. Studenski, S., Hayes, R.P., Leibowitz, R.Q., Bode, R., Lavery, L., Walston, J., et al. 2004. Clinical global impression of change in physical frailty: development of a measure based on clinical judgment. J. Am. Geriatr. Soc. 52: 1560-1566. doi:10.1111/j.1532-5415.2004.52423.x. PMID:15341562.
138. Surakka, J., Romberg, A., Ruutiainen, J., Aunola, S., Virtanen, A., Karppi, S.-L., et al. 2004. Effects of aerobic and strength exercise on motor fatigue in men and women with multiple sclerosis: a randomized controlled trial. Clin. Rehabil. 18: 737-746. doi:10.1191/0269215504cr780oa. PMID:15573829.
139. Syddall, H., Cooper, C., Martin, F., Briggs, R., and Sayer, A.A. 2003. Is grip strength a useful single marker of frailty? Age Ageing, 32: 650-656. doi:10.1093/ageing/afg111. PMID:14600007.
140. Theou, O., Jones, G.R., and Brown, L.E. 2008. The effect of restinterval on recovery between resistance exercise sets in young and old women. J. Strength Cond. Res., In press.
141. Theou, O., and Kloseck, M. 2008. Tools to identify communitydwelling older adults in different stages of frailty. Phys. Occup. Ther. Geriatr. 26: 1-21.
142. Tomlinson, B.E., and Irving, D. 1977. The numbers of limb motor neurons in the human lumbosacral cord throughout life. J. Neurol. Sci. 34: 213-219. doi:10.1016/0022-510X(77)90069-7. PMID:925710.
143. Trappe, T.A., White, F., Lambert, C.P., Cesar, D., Hellerstein, M., and Evans, W.J. 2002. Effect of ibuprofen and acetaminophen on postexercise muscle protein synthesis. Am. J. Physiol. Endocrinol. Metab. 282: E551-E556. PMID:11832356.
144. Valkeinen, H., Hakkinen, A., Hannonen, P., Hakkinen, K., and Alen, M. 2006. Acute heavy-resistance exercise-induced pain and neuromuscular fatigue in elderly women with fibromyalgia and in healthy controls. Arthritis Rheum. 54: 1334-1339. doi:10.1002/art.21751. PMID:16575859.
145. van der Wielen, R.P., Lowik, M.R., van den Berg, H., de Groot, L.C., Haller, J., Moreiras, O., et al. 1995. Serum vitamin D concentrations among elderly people in Europe. Lancet, 346: 207-210. PMID:7616799.
146. Vandervoort, A.A. 2002. Aging of the human neuromuscular system. Muscle Nerve, 25: 17-25. doi:10.1002/mus.1215. PMID:11754180.
147. Vandervoort, A.A., and Symons, T.B. 2001. Functional and metabolic consequences of sarcopenia. Can. J. Appl. Physiol. 26: 90-101. PMID:11173671.
148. Vollestad, N.K. 1997. Measurement of human muscle fatigue. J. Neurosci. Methods, 74: 219-227. doi:10.1016/S0165-0270(97)02251-6. PMID:9219890.
149. Walston, J., and Hadley, E.C., Ferrucci, L., Guralnik, J.M., Newman, A.B., Studenski, S.A., et al. 2006. Research agenda for frailty in older adults: toward a better understanding of physiology and etiology: summary from the American Geriatrics Society/National Institute on Aging Research Conference on Frailty in Older Adults. J. Am. Geriatr. Soc. 54: 991-1001.
150. Wicherts, I.S., van Schoor, N.M., Boeke, A.J.P., Visser, M., Deeg, D.J.H., Smit, J., et al. 2007. Vitamin D status predicts physical performance and its decline in older persons. J. Clin. Endocrinol. Metab. 92: 2058-2065. doi:10.1210/jc.2006-1525. PMID:17341569.
151. Wideman, L., Weltman, J.Y., Hartman, M.L., Veldhuis, J.D., and Weltman, A. 2002. Growth hormone release during acute and chronic aerobic and resistance exercise: recent findings. Sports Med. 15: 987-1004.
152. Wolfe, R.R. 2006. The underappreciated role of muscle in health and disease. Am. J. Clin. Nutr. 84: 475-482. PMID:16960159.
153. Wolff, J.L., Starfield, B., and Anderson, G. 2002. Prevalence, expenditures, and complications of multiple chronic conditions in the elderly. Arch. Intern. Med. 162: 2269-2276. doi:10.1001/archinte.162.20.2269. PMID:12418941.
154. Wolfson, L., Judge, J., Whipple, R., and King, M. 1995. Strength is a major factor in balance, gait, and the occurrence of falls. J. Gerontol. A Biol. Sci. Med. Sci. 50: 64-67. PMID:7493221.
155. Woods, N.F., LaCroix, A.Z., Gray, S.L., Aragaki, A., Cochrane, B.B., Brunner, R.L., et al. 2005. Frailty: emergence and consequences in women aged 65 and older in the women's health initiative observational study. J. Am. Geriatr. Soc. 53: 1321-1330. doi:10.1111/j.1532-5415.2005.53405.x. PMID:16078957.
156. Yassierli and Nussbaum, M.A. 2007. Muscle fatigue during intermittent isokinetic shoulder abduction: age effects and utility of electromyographic measures. Ergonomics. 50: 1110-1126. doi:10.1080/00140130701308716. PMID:6434323.
157. Young, A., Stokes, M., and Crowe, M. 1984. Size and strength of the quadriceps muscles of old and young women. Eur. J. Clin. Invest. 14: 282-287. doi:10.1111/j.1365-2362.1984.tb01182.x. PMID:6434323.