MacKelvie Kerry J, Khan Karim M, Petit Moira A, Janssen Patricia A, McKay Heather A
Endocrinology and Diabetes Unit, British Columbia Children's Hospital and Food, Nutrition and Health, Canada.
Pediatrics. 2003 Dec;112(6 Pt 1):e447. doi: 10.1542/peds.112.6.e447.
Childhood weight-bearing physical activity is recognized as an important determinant of peak bone mass, and physical activity intervention may represent a feasible strategy for primary prevention of osteoporosis. Previous school-based exercise interventions have all been of <10 months in duration. We implemented a high-impact, circuit-based, jumping intervention (10 minutes, 3 times a week) over 2 school years and compared changes in bone mineral content (BMC) over 20 months (2 school years) in 9.9 +/- 0.6-year-old intervention girls (N = 32) and controls (10.3 +/- 0.4 years, N = 43).
We measured BMC for the total body, lumbar spine, proximal femur (and femoral neck and trochanteric subregions), and lean and fat mass by dual-energy radiograph absorptiometry (Hologic QDR 4500), and height, sitting height, leg length, and weight at baseline and 20 months. We assessed Tanner stage, general physical activity, and calcium intake by questionnaire.
Girls were Tanner breast stage 1 to 3 at baseline. There were no significant differences in baseline or 20-month change in body size or composition, average physical activity, or calcium intake between groups. There were substantially greater gains in lumbar spine (41.7% vs 38.0%) and femoral neck (24.8% vs 20.2%) BMC in intervention than in control girls (P <.05, analysis of covariance; covariates were baseline BMC and height, change in height, physical activity, and final Tanner stage).
Three brief sessions of high-impact exercise per week implemented over 2 consecutive years within the elementary school curriculum elicited a substantial bone mineral accrual advantage in pubertal girls.
儿童负重体育活动被认为是峰值骨量的重要决定因素，体育活动干预可能是骨质疏松症一级预防的可行策略。以往基于学校的运动干预持续时间均不足10个月。我们在两个学年内实施了一项高强度、循环式跳跃干预（每次10分钟，每周3次），并比较了9.9±0.6岁的干预组女孩（N = 32）和对照组（10.3±0.4岁，N = 43）在20个月（两个学年）内骨矿物质含量（BMC）的变化。
我们通过双能X线吸收法（Hologic QDR 4500）测量全身、腰椎、股骨近端（以及股骨颈和转子亚区域）的BMC以及瘦体重和脂肪量，并在基线和20个月时测量身高、坐高、腿长和体重。我们通过问卷调查评估坦纳分期、一般体育活动和钙摄入量。
女孩在基线时处于坦纳乳房分期1至3期。两组之间在基线或20个月时的身体大小或组成、平均体育活动或钙摄入量方面没有显著差异。与对照组女孩相比，干预组女孩腰椎（41.7%对38.0%）和股骨颈（24.8%对20.2%）的BMC增加幅度明显更大（协方差分析，P <.05；协变量为基线BMC和身高、身高变化、体育活动以及最终坦纳分期）。
在小学课程中连续两年每周进行三次简短的高强度运动，在青春期女孩中产生了显著的骨矿物质积累优势。
