Aging Rehabilitation Research Center, University of Florida, PO Box 112610, Gainesville, FL 32611.
J Gerontol A Biol Sci Med Sci. 2014 Jan;69(1):101-8. doi: 10.1093/gerona/gls337. Epub 2013 May 16.
Accumulating evidence suggests that both dietary restriction and exercise (DR + E) should be incorporated in weight loss interventions to treat obese, older adults. However, more information is needed on the effects to lower extremity tissue composition-an important consideration for preserving mobility in older adults.
Twenty-seven sedentary women (body mass index: 36.3±5.4kg/m(2); age: 63.6±5.6 yrs) were randomly assigned to 6 months of DR + E or a health education control group. Thigh and calf muscle, subcutaneous adipose tissue (SAT), and intermuscular adipose tissue (IMAT) size were determined using magnetic resonance imaging. Physical function was measured using a long-distance corridor walk and knee extension strength.
Compared with control, DR + E significantly reduced body mass (-6.6±3.7kg vs control: -0.05±3.5kg; p < .01). Thigh and calf muscle volumes responded similarly between groups. Within the DR + E group, adipose tissue was reduced more in the thigh than in the calf (p < .04). Knee extension strength was unaltered by DR + E, but a trend toward increased walking speed was observed in the DR + E group (p = .09). Post hoc analyses showed that reductions in SAT and IMAT within the calf, but not the thigh, were associated with faster walking speed achieved with DR + E (SAT: r = -0.62; p = .01; IMAT: r = -0.62; p = .01).
DR + E preserved lower extremity muscle size and function and reduced regional lower extremity adipose tissue. Although the magnitude of reduction in adipose tissue was greater in the thigh than the calf region, post hoc analyses demonstrated that reductions in calf SAT and IMAT were associated with positive adaptations in physical function.
越来越多的证据表明，限制饮食和运动（DR + E）应该被纳入肥胖老年人的减肥干预措施中。然而，我们需要更多关于降低下肢组织成分的信息——这对于保持老年人的活动能力非常重要。
27 名久坐不动的女性（体重指数：36.3±5.4kg/m²；年龄：63.6±5.6 岁）被随机分配到 6 个月的 DR + E 或健康教育对照组。使用磁共振成像确定大腿和小腿肌肉、皮下脂肪组织（SAT）和肌肉间脂肪组织（IMAT）的大小。使用长距离走廊行走和膝关节伸展力量来测量身体功能。
与对照组相比，DR + E 显著降低了体重（-6.6±3.7kg 与对照组：-0.05±3.5kg；p <.01）。大腿和小腿肌肉体积在两组之间的反应相似。在 DR + E 组中，大腿脂肪减少量大于小腿（p <.04）。DR + E 对膝关节伸展力量没有影响，但观察到 DR + E 组的行走速度有增加的趋势（p =.09）。事后分析表明，小腿而非大腿的 SAT 和 IMAT 减少与 DR + E 实现的更快行走速度相关（SAT：r = -0.62；p =.01；IMAT：r = -0.62；p =.01）。
DR + E 保持了下肢肌肉的大小和功能，并减少了下肢的局部脂肪组织。尽管大腿区域的脂肪减少量大于小腿区域，但事后分析表明，小腿 SAT 和 IMAT 的减少与身体功能的积极适应相关。
