背景：步行能力衰退是伴隨老化常見的現象。保持身體質量指數(Body Mass Index, BMI)適中和多運動皆有助於維持步行能力，但二者合併的效應則不清楚。
目的：故本研究目的在探討身體質量指數與運動對預防台灣中老年人步行能力衰退之組合效應。
方法：本研究分析「中老年調查」2003及2007年的資料庫。排除非本人作答、嚴重心智功能缺損、中風及有日常生活活動功能失能者，共有3,380位(加權後)50歲以上中老年人納入分析。依據受訪者二年度走完200-300公尺結果，評定其步行能力是否衰退。控制基本人口學、健康狀況及健康行為，以羅吉斯迴歸分析BMI與運動對步行能力衰退的個別和組合效應。
結果：以個別變項分析中，肥胖(OR=1.79, p=0.001)及運動(OR=0.61, p=0.002)與步行能力衰退有顯著關聯。在組合變項分析中，過輕且不運動者(OR=2.82, p<0.001)、及肥胖且不運動者(OR=2.82, p<0.001)步行能力衰退的風險，皆明顯高於BMI適中且有運動者。
結論：本研究之組合分析可彰顯同時保持BMI適中且多運動，對預防步行能力衰退風險的好處。研究結果讓民眾更容易及清楚地瞭解維持正常體重及日常運動對維持良好步行能力的重要，也可供健康促進政策之參考。

Background: Decline in walking ability is a result along with aging. Maintaining a proper Body Mass Index (BMI) and higher level of physical activities are helpful to prevent walking ability decline; however, their combined effect is not clear.
Objective: The study aimed to determine the combined effect of BMI and physical activities on walking ability decline in older Taiwanese. Methods: This study analyzed the datasets of 2003 and 2007 "Taiwan Longitudinal Study on Aging". After exclusion of not self-reported, severe mental disorders, stroke and disabled in one or more items of activities of daily living functions, there were 3,380 subjects (weighted) over 50 years old included in the analysis. According to the responses of "walking 200-300 meters" in the two years, subjects were classified as decline or not. By controlling for demographic, health status and health behaviors, logistic regression was used to analyze the independent and combined effects of BMI and physical activity on walking ability decline. Results: When analyzed independently, obesity (OR=1.79, p=0.001) and physical activity, (OR=0.61, p=0.002) were associated with walking ability decline. In the analysis of the combined variable of BMI and physical activity, subjects who were underweight and no physical activity (OR=2.82, p<0.001) and who were obese and no physical activity (OR=2.82, p<0.001) were more likely to decline in walking ability than those who had proper BMI and physical activities.
Results: When analyzed independently, obesity (OR=1.79, p=0.001) and physical activity, (OR=0.61, p=0.002) were associated with walking ability decline. In the analysis of the combined variable of BMI and physical activity, subjects who were underweight and no physical activity (OR=2.82, p<0.001) and who were obese and no physical activity (OR=2.82, p<0.001) were more likely to decline in walking ability than those who had proper BMI and physical activities.
Conclusion: The combined analysis method manifests the advantage of keeping proper BMI and physical activities simultaneously to prevent walking ability decline. The results could make people more easily and clearly understand the importance of keeping proper BMI and physical activities to maintain good walking ability. It could also provide the basis for a nation policy of health promotion.

目錄
第一章 緒 論 1
第一節 研究背景和動機 1
第二節 研究目的 2
第二章 研究方法 3
第一節 研究架構 3
第二節 資料來源及研究對象 4
第三節 測量工具及操作型定義 6
第四節 資料分析方法 7
第三章 結 果 8
第四章 討 論 10
第一節 運動與BMI的個別效應 10
第二節 運動與BMI組合變項 11
第三節 其他變項與步行能力之關係 12
第四節 本研究優勢與限制 13
第五章 結論與建議 15
參考文獻 16

表目錄
表一、研究樣本之社會人口學、健康狀況及健康行為相關變項之分布，及其與步行能力衰退之關聯分析 22
表二、以羅吉斯回歸分析運動與身體質量指數個別變項及組合變項對預測步行能力衰退之關聯 24

Prohaska TR, Anderson LA, Binstock RH. editors. Public Health for an Aging Society. Baltimore, MD: John Hopkins University Press. 2012
Hutton D. Older Persons in Emergencies: Considerations for Action and Policy Development. Geneva: World Health Organization 2008:1-38.
行政院衛生署：長期照護服務網計畫（第一期）－102年至105年。引用http://www.ey.gov.tw/Upload/RelFile/27/704779/3689ac5a-f059-431a-8b6b-07d9c2116789.pdf。引用2014/06/05。
Nagi SZ. An epidemiology of disability among adults in the United States. Milbank Mem Fund Q 1976;54:439-68.
Lawton MP, Brody EM. Assessment of older people: self-maintaining and instrumental activities of daily living. Gerontologist 1969;9:179-86.
Katz S, Ford AB, Moskowitz RW, Jackson BA, Jaffe MW. Studies of illness in the aged. The index of ADL: a standardized measure of biological and psychosocial function. JAMA 1963;185:914-9.
Barberger-Gateau P, Rainville C, Letenneur L, Dartigues JF. A hierarchical model of domains of disablement in the elderly: a longitudinal approach. Disabil Rehabil 2000;22:308-17.
Buchman AS, Boyle PA, Wilson RS, Bienias JL, Bennett DA. Physical activity and motor decline in older persons. Muscle Nerve 2007;35:354-62.
Buchman AS, Wilson RS, Boyle PA, Bienias JL, Bennett DA. Change in motor function and risk of mortality in older persons. J Am Geriatr Soc 2007;55:11-9.
Seeman TE, Charpentier PA, Berkman LF, Tinetti ME, Guralnik JM, Albert M, Blazer D, Rowe JW. Predicting changes in physical performance in a high-functioning elderly cohort: MacArthur studies of successful aging. J Gerontol 1994;49:97-108.
Hulens M, Vansant G, Claessens AL, Lysens R, Muls E. Predictors of 6-minute walk test results in lean, obese and morbidly obese women. Scand J Med Sci Sports 2003;13:98-105.
Feinglass J, Song J, Manheim LM, Semanik P, Chang RW, Dunlop DD. Correlates of improvement in walking ability in older persons in the United States. Am J Public Health 2009;99:533-9.
Patel KV, Coppin AK, Manini TM, Lauretani F, Bandinelli S, Ferrucci L, Guralnik JM. Midlife physical activity and mobility in older age: the InCHIANTI study. Am J Prev Med 2006;31:217-24.
Stenholm S, Rantanen T, Alanen E, Reunanen A, Sainio P, Koskinen S. Obesity as a risk factor for walking limitation in older Finnish men and women. Obesity 2007;15:929-38.
Riebe D, Blissmer BJ, Greaney ML, Garber CE, Lees FD, Clark PG. The relationship between obesity, physical activity, and physical function in older adults. J Aging Health 2009;21:1159-78.
LaCroix AZ, Guralnik JM, Berkman LF, Wallace RB, Satterfield S. Maintaining mobility in late life. II. Smoking, alcohol consumption, physical activity, and body mass index. Am J Epidemiol 1993;137:858-69.
Knoops KT, de Groot LC, Kromhout D, Perrin AE, Moreiras-Varela O, Menotti A, van Staveren WA. Mediterranean diet, lifestyle factors, and 10-year mortality in elderly European men and women: the HALE project JAMA 2004;292:1433-9.
Khaw KT, Wareham N, Bingham S, Welch A, Luben R, Day N. Combined impact of health behaviours and mortality in men and women: the EPIC-Norfolk prospective population study. PLoS Med 2008;5:e12.
行政院衛生署國民健康局：中老年身心社會生活狀況長期追蹤調查系列調查簡介。取自http://www.hpa.gov.tw/BHPNet/WEB/Healthtopic/TopicArticle.aspx?No=200712270015&parentid=200712270002。引用2014/06/05。
Misic MM, Rosengren KS, Woods JA, Evans EM. Muscle quality, aerobic fitness and fat mass predict lower-extremity physical function in community-dwelling older adults. Gerontology 2007;53:260-6.
Lang IA, Guralnik JM, Melzer D. Physical activity in middle-aged adults reduces risks of functional impairment independent of its effect on weight. J Am Geriatr Soc 2007;55:1836-41.
Chou CH, Hwang CL, Wu YT. Effect of exercise on physical function, daily living activities, and quality of life in the frail older adults: a meta-analysis. Arch Phys Med Rehabil 2012;93:237-44.
de Vries NM, van Ravensberg CD, Hobbelen JS, Olde Rikkert MG, Staal JB, Nijhuis-van der Sanden MW. Effects of physical exercise therapy on mobility, physical functioning, physical activity and quality of life in community-dwelling older adults with impaired mobility, physical disability and/or multi-morbidity: a meta-analysis. Ageing Res Rev 2012;11:136-49.
Stenholm S, Sainio P, Rantanen T, Koskinen S, Jula A, Heliövaara M, Aromaa A. High body mass index and physical impairments as predictors of walking limitation 22 years later in adult Finns. J Gerontol A Biol Sci Med Sci 2007;62:859–65.
Vincent HK, Vincent KR, Lamb KM. Obesity and mobility disability in the older adult. Obes Rev 2010;11:568-79.
Hergenroeder AL, Wert DM, Hile ES, Studenski SA, Brach JS. Association of body mass index with self-report and performance-based measures of balance and mobility. Phys Ther 2011:91:1223-34.
Evans EM, Rowe DA, Racette SB, Ross KM, McAuley E. Is the current BMI obesity classification appropriate for black and white postmenopausal women? Int J Obes 2006:30:837–43.
Schaap LA, Koster A, Visser M. Adiposity. Muscle mass, and muscle strength in relation to functional decline in older persons. Epidemiol Rev 2012;35:51-65.
Field AE, Coakley EH, Must A, Spadano JL, Laird N, Dietz WH, Rimm E, Colditz GA. Impact of overweight on the risk of developing common chronic diseases during a 10-year period. Arch Intern Med 2001;161:1581-6.
Kopelman PG. Obesity as a medical problem. Nature 2000:404:635–43.
Manini TM, Newman AB, Fielding R, Blair SN, Perri MG, Anton SD, Goodpaster BC, Katula JA, Rejeski WJ, Kritchevsky SB, Hsu FC, Pahor M, King AC, LIFE Research Group. Effects of exercise on mobility in obese and nonobese older adults. Obesity 2010;18:1168-75.
Payette H, Hanusaik N, Boutier V, Morais JA, Gray-Donald K. Muscle strength and functional mobility in relation to lean body mass in free-living frail elderly women. Eur J Clin Nutr 1998;52:45-53.
Locher JL, Roth DL, Ritchie CS, Cox K, Sawyer P, Bodner EV, Allman RM. Body mass index, weight loss, and mortality in community-dwelling older adults. J Gerontol A Biol Sci Med Sci 2007;62:1389-92.
Strawbridge WJ, Kaplan GA, Camacho T, Cohen RD. Thw dynamics of disability and functional change in an elderly cohort: Results from the Alameda County Study. J Am Geriatr Soc 1992; 40:799-806.
Marengoni A, von Strauss E, Rizzuto D, Winblad B, Fratiglioni L. The impact of chronic multimorbidity and disability on functional decline and survival in elderly persons. A community-based, longitudinal study. J Intern Med 2009;265:288-95.
沈惠民、林東亮、鍾進燈、許惠恒：糖尿病足之臨床評估與治療。內科學誌 2011；22：254-65。
蔡璧光、劉芹芳、許心恬：應用腳踏復健器之運動方案改善心臟衰竭個案之活動無耐力。護理雜誌 2012；59：103-10。
沈明輝：影響社區老人身體功能退化的因素。台北市：國立臺灣大學； 2002；88頁。
Villareal DT, Chode S, Parimi N, Sinacore DR, Hilton T, Armamento-Villareal R, Napoli N, Qualls C, Shah K. Weight loss, exercise, or both and physical function in obese older adults. N Engl J Med 2011;364:1218-29.
Vincent HK, Mathews A. Obesity and mobility in advancing age: mechanisms and interventions to preserve independent mobility. Ageing Res Rev 2012;11:361–73.