阻力訓練與階梯有氧運動對停經後婦女骨質密度、體適能與性荷爾蒙之影響

Abstract

目的：探討6個月阻力與階梯有氧運動訓練在3、6個月與追蹤3個月對停經後婦女(postmenopausal women, PMW)骨質密度(bone mineral density, BMD)、體適能與性荷爾蒙之影響。方法：將54位未接受荷爾蒙補充治療、自然停經、未規律運動之女性（平均年齡55.19 ± 3.65歲）隨機分成運動組（EX1、EX2，接受3次/週、1小時/次、持續6個月之訓練，平均出席率92.12 ± 10.73%）與未參與規律運動的對照組(C)。EX1為阻力訓練（13個肌肉群，1~3組，反覆次數8~25次，強度為50~60%最大心跳保留率）；EX2為階梯有氧（強度為55~85%最大心跳保留率）；在基準值、3、6個月與追蹤3個月以雙能量X光吸收測量儀檢測腰椎、股骨頸之BMD與體適能，並在基準值、3個月與追蹤3個月抽血檢驗血清中雌二醇(Estradiol, E2)與睪固酮(Testosterone, T)濃度，將檢測資料以皮爾森積差相關、混合設計二因子共變數分析，顯著水準訂為a=.05。結果：(1)三組在腰椎、股骨頸骨質密度組內與組間皆未達顯著差異；(2) 3個月時，EX1、EX2分別與C在八呎立走、六分鐘走組間達顯著差異；(3) 6個月時，EX1、EX2分別與C在體脂肪、身體活動量、八呎立走與六分鐘走組間達顯著差異；追蹤3個月時，EX1、EX2分別與C在六分鐘走組間達顯著差異；(4) 3個月之EX1、EX2分別與基準值比較，在八呎立走有顯著效果；3、6個月之EX1分別與基準值比較，在六分鐘走有顯著效果；(5) EX1在追蹤3個月與EX2之T濃度組間達顯著差異；(6)與追蹤3個月比較，EX2分別在基準值、3個月之T達顯著降低；C則在3個月之T濃度有顯著降低；(7)與基準值比較，6個月之EX1、EX2可顯著改善體脂肪與八呎立走，但追蹤3個月與6個月訓練比較，八呎立走退步亦達顯著；(8)與3個月比較，6個月EX2在八呎立走達顯著進步；(9)與基準值比較，3個月EX1在由坐到站三十秒有顯著進步，且效果至少維持3個月；(10)BMD與體重成正相關；體適能與體重成負相關；性荷爾蒙未與體重、BMD或體適能相關。結論：(1) 6個月的運動訓練可維持PMW腰椎、大腿股骨頸之BMD，其效果可持續維持至少3個月；(2) 3個月與6個月的運動訓練對PMW的體適能與功能性皆有改善與維持的正面效果；(3)運動訓練對PMW之性荷爾蒙變化似乎沒有直接的影響。Purpose: To investigate the effect of resistance training (EX1) and bench-step aerobic training (EX2) at 3-, 6-month, and 3-month follow-up on bone mineral density (BMD), Physical fitness, and sex hormone levels in postmenopausal women (PMW). Methods: 54 women (mean age were 55.19 ± 3.65 year-old) who were sedentary, nature menopause, and not on hormone replacement therapy were randomly divided into two exercise groups and a sedentary control group (C). EX1 consisted of resistance exercise training (13 muscle groups, 1-3 sets, 8-25 repetitions, 50~60% maximal heart rate reserve, MHRr), and EX2 included bench step aerobic exercise (55~85% MHRr), with training 3 times per week, 60 minutes per session for 6 months. BMD was determined using dual-energy x-ray absorptiometry (DEXA) at the lumbar spine and femur neck at baseline, 3-, 6-month, and 3-month follow-up. Physical fitness was assessed at four time points. Estradiol (E2) and testosterone (T) levels were assessed using chemiluminescence by the ADVIA Centaur® system (BAYER) at baseline, 3-month, and 3-month follow-up. All data were analyzed using Pearson correlations and a mixed two-way ANCOVA design. The significance level adopted was a=.05. Results: (1) There were no sig. difference between and within groups in BMD at the lumbar spine and femur neck; (2) EX1, EX2 were sig. different from C in 8-foot up-and-go and 6-min. walk at 3-month; (3) EX1, EX2 were sig. different from C in body fat, physical activities, 8-foot up-and-go, and 6-min. walk at 6-month; and in 6-min. walk at 3-month follow-up; (4) Compared to baseline, EX1 and EX2 in 8-foot up-and-go were sig. improved at 3-month; and compared to baseline,EX1 in 6-min. walk was sig. improved at 3-, 6-month; (5) EX1 was sig. different from EX2 in T levels at 3-month; (6) Compared to 3-month follow-up, EX2 levels for T were sig. decreased at baseline and 3-month respectively; also in addition, C exhibited sig. decreases in T levels at 3-month; (7) Compared to baseline, EX1 and EX2 were significantly improved in body fat and 8-foot up-and-go at 6-month; and compared to 6-month, 8-foot up-and-go sig. declined at 3-month follow-up; (8) Compared to 3-month, EX2 were significantly improved in 8-foot up-and-go at 6-month; (9) Compared to baseline, EX1 significantly improved in 30-sec. chair stand at 6-month, and the effect lasted at least 3 months into follow-up; (10) BMD was positively related to weight. Physical fitness was negatively related to weight, and sex-hormone levels were not related to weight, BMD, physical activity level, or physical fitness. Conclusion: (1) 6-month exercise training can maintain BMD at the lumbar spine and femur neck in PMW; and the effect could last at least 3 months post training. (2) 3-month and 6-month exercise training can improve and maintain functional physical fitness in PMW. (3) Exercise training was not shown to affect sex hormone levels in PMW.