Serra M C, Blumenthal J B, Ryan A S
Baltimore Maryland VA Medical Center & University of Maryland School of Medicine, USA.
J Aging Res Clin Pract. 2013 Mar;2(1):11-16.
Weight loss is often recommended for obese women to reduce fat mass and the risk of developing chronic diseases, but may result in a reduction of bone mineral density (BMD). African Americans have greater BMD than Caucasians, but differences in the decrease in BMD between these races following weight reduction with and without exercise are unknown.
The purpose of this study was to investigate the hypothesis that Caucasian women would lose greater amounts of BMD than African American women after undergoing weight loss, but that the addition of aerobic exercise would attenuate the loss in both races.
Longitudinal.
African American (n=34) and Caucasian (n=63), overweight and obese postmenopausal (age 45-80 years).
Six months of weight loss (250-350 kcal/days deficit) alone (WL) or in combination with aerobic exercise consisting of 3 days/week treadmill training at >85% of heart rate reserve for 45 min (AEX+WL).
Femoral neck, total femur, and lumbar BMD, VO2max, urinary calcium, and dietary intake.
African American women had a greater body weight, BMI, and BMD all sites and lower dietary protein and calcium intakes than Caucasian women (all P<0.05). Weight decreased 7.5% in both groups and VO2max increased only after AEX+WL (intervention effect, P<0.001). Both races lost ~1% of their femoral neck and total femur BMD following the interventions (P's<0.01). There were no race by intervention interactions. There was a trend for the women undergoing WL to lose greater femoral neck BMD than those in AEX+WL (P=0.07). There were no associations between changes in BMD and changes in VO2max, urinary calcium, or dietary intake.
Our data indicate that despite beginning the interventions with greater BMD than Caucasian postmenopausal women, African Americans were not spared from losses of femoral neck and total femur BMD following six months of weight loss, but that addition of aerobic exercise to weight loss tends to attenuate the decreases in femoral neck BMD in both races.
通常建议肥胖女性减肥以减少脂肪量和患慢性病的风险，但减肥可能会导致骨矿物质密度（BMD）降低。非裔美国人的骨密度高于白种人，但在有运动和无运动的情况下减肥后，这两个种族的骨密度下降差异尚不清楚。
本研究的目的是调查以下假设：白种女性在减肥后骨密度的损失量会比非裔美国女性更大，但有氧运动可减轻两个种族的骨密度损失。
纵向研究。
非裔美国人（n = 34）和白种人（n = 63），超重和肥胖的绝经后女性（年龄45 - 80岁）。
单独进行六个月的减肥（每天热量摄入 deficit 250 - 350千卡）（WL），或与有氧运动相结合，包括每周3天进行跑步机训练，心率储备超过85%，持续45分钟（AEX + WL）。
股骨颈、全股骨和腰椎的骨密度、最大摄氧量、尿钙和饮食摄入量。
非裔美国女性的体重、体重指数、所有部位的骨密度均高于白种女性，而饮食中的蛋白质和钙摄入量低于白种女性（所有P < 0.05）。两组体重均下降7.5%，仅在AEX + WL后最大摄氧量增加（干预效应，P < 0.001）。干预后，两个种族的股骨颈和全股骨骨密度均下降约1%（P值 < 0.01）。种族与干预之间没有交互作用。进行WL的女性股骨颈骨密度损失趋势大于AEX + WL组的女性（P = 0.07）。骨密度变化与最大摄氧量、尿钙或饮食摄入量变化之间没有关联。
我们的数据表明，尽管非裔美国绝经后女性开始干预时的骨密度高于白种女性，但在减肥六个月后，她们的股骨颈和全股骨骨密度仍未能幸免下降，不过在减肥的同时增加有氧运动往往会减轻两个种族股骨颈骨密度的下降。
