阻力訓練於老年第2型糖尿病患者骨骼肌失能之效果

Abstract

背景和目的：老年糖尿病患者由於老化因素與疾病進程，易引起肌肉結構與身體功能表現改變，進而產生骨骼肌失能，然而過去文獻少有以阻力運動訓練介入老年糖尿病患者骨骼肌失能的實證。本研究目的為探討12週阻力運動訓練對老年第2型糖尿病患者，對於骨骼肌功能、血糖�血脂控制、功能容量與生活品質的效果。方法：本研究從門診與社區徵召23位老年第2型糖尿病患者（平均年齡71.1±4.2歲），受試者經基準點（baseline）評估後均接受一次關於糖尿病的一般衛教，再以性別分層隨機分配至運動組（n=11）或控制組（n=12）。運動組接受12週、每週3次的漸進式阻力運動訓練（progressive resistance training），所有運動訓練在物理治療師監督下進行，每次運動訓練包括5分鐘暖身、8種阻力運動、以及5分鐘緩和運動。阻力運動以槓片、啞鈴或身體重量作為阻力來源，運動目標強度由40-50% 1-RM漸進至75% 1-RM。控制組僅接受12週的常規治療，並維持現有身體活動量。所有受試者均於基準點和第12週追蹤點進行兩次評估，評估項目包括胸部推舉、大腿推蹬最大肌力、身體功能、最大攝氧量、運動時肌肉氧合反應與生活品質。血液生化參數相關評估有空腹血糖、糖化血色素和血脂。運動組患者於第6週進行上下肢最大肌力與身體功能評估，作為後續運動訓練強度調整之依據。結果：經12週的阻力運動訓練後，運動組較介入前在上肢胸部推舉肌力（57.7±21.1磅進步到65.5±19.2磅，p=0.023）和下肢大腿推蹬肌力（125.4±30.8公斤進步到184.1±32.7公斤，p<0.0005）均有顯著進步，運動組介入後的腰圍和體脂肪較介入前顯著減少，然上述參數均不具組間明顯差異。在血糖和血脂控制方面，兩組受試者均無顯著組間或組內差異，運動組經介入後空腹血糖有減少的趨勢（p=0.047）、控制組有總膽固醇增加和高密度脂蛋白減少的趨勢。運動組骨骼肌氧合度則在介入後較介入前顯著改善，運動訓練後運動組完成五次坐到站所需時間和一分鐘坐到站次數均有改善的趨勢。結論：老年糖尿病患者經12週的阻力運動後，其最大肌力、身體組成和肌肉功能均較介入前顯著改善，身體功能、血糖控制則有改善的趨勢。

Background and Purpose: Changes of muscle structure and physical function are commonly seen in the elderly or type 2 diabetes mellitus (T2DM), which contributes to the dysfunction of skeletal muscle. However, evidence about the effects of resistance training on the skeletal muscle dysfunction in older adults with diabetes was limited. The purpose of this study was to investigate the effect of a 12-week progressive resistance training program on the skeletal muscle function, glycemic control, lipid profile, functional capacity, and quality of life in the elderly with T2DM. Methods: Twenty-three T2DM patients, aged 71.1±4.2 years, were recruited from the community or the clinics of a medical center in Taipei, Taiwan. All participants received baseline assessment and a brochure specifically designed for T2DM about the general principles of exercise, nutrition, and diet. They were then stratified by gender and randomly assigned to either exercise group (n=11) or control group (n=12) after baseline measurement. Participants in the exercise group received progressive resistance training programs 3 times a week for 12 weeks, while participants in the control group were asked to maintain their current activity level. All resistance training programs were performed by the participants in the exercise group under the supervision of physical therapists. The resistance training program consisted of 5 minutes of warm-up, resistance training with 8 exercises, and 5 minutes of cool-down using dumbbell or weights. Training intensity was initially set at 40-50% of 1-repetition maximum (1-RM) and progressive to 75% of 1-RM. Measures were taken at baseline and after 12 weeks of exercise training or control period. Outcome measures included maximal strength of chess press and leg press, physical function performance, muscle oxygenation during exercise, maximal oxygen consumption, and quality of life. Venous blood samples were obtained for analyses of fasting glucose, glycated hemoglobin, and lipid profile. An additional assessment was performed at the sixth week to reassess maximal muscle strength and physical function of the participants in the exercise group. Results: The participants in the exercise group showed significant improvement in maximal strength of chest press (57.7±21.1 lb to 65.5±19.2 lb, p=0.023) and leg press (125.4±30.8 kg to 184.1±32.7 kg, p<0.0005) after 12 weeks of resistance exercise. Significant decreases of waist circumference and percentage of body fat were also found after intervention in the exercise group. However, no significant between-group effect was found in muscle strength or body composition. There was no significant between-group or within-group effect in the changes of glycemic control or lipid profile. A trend of decrease in fasting glucose was observed in the exercise group (p=0.047), while trends for elevated total cholesterol and decreased high-density lipoprotein was found in the control group. Muscle oxygenation during exercise was improved within exercise group after resistance training. Physical function performance such as time for five repetitions of sit-to-stand or one minute sit-to-stand test was improved in the exercise group, but it did not reach within-group statistical significance. Conclusions: Muscle strength, body composition, and muscle function were found to be improved in elderly patients with T2DM after 12 weeks of resistance training; only a trend of improvement in physical function and glycemic control was observed.