TY - JOUR
T1 - Early physical activity provides sustained bone health benefits later in childhood
AU - Janz, Kathleen F.
AU - Letuchy, Elena M.
AU - Eichenberger Gilmore, Julie M.
AU - Burns, Trudy L.
AU - Torner, James C.
AU - Willing, Marcia C.
AU - Levy, Steven M.
PY - 2010/6
Y1 - 2010/6
N2 - PURPOSE: This study examined the potential effect of early childhood moderate and vigorous physical activity (MVPA) on later bone health. METHODS: Three hundred and thirty-three children, participating in the Iowa Bone Development Study, were studied at ages 5, 8, and 11 yr. MVPA (min•d -1) was measured using an accelerometry-based physical activity monitor. Bone mineral content (BMC; g) of the whole body, lumbar spine, and hip was measured using dual-energy X-ray absorptiometry. Mixed regression models were used to test whether MVPA at age 5 yr had an effect on BMC at ages 8 and 11 yr after adjustment for concurrent height, weight, age, maturity, and MVPA. The analysis was repeated to control for bone outcomes at age 5 yr. Mixed-model least-squares mean values at the person level of covariates for age group were used to compare the BMC at ages 8 and 11 yr of children in the highest and lowest quartiles of MVPA at age 5 yr. RESULTS: For boys and girls, MVPA at age 5 yr predicted BMC adjusted for concurrent height, weight, age, maturity, and MVPA at ages 8 and 11 yr (P < 0.05). When the analysis was repeated to also control for BMC at age 5 yr, the effect of MVPA at age 5 yr was significant for boys but not for girls. Boys and girls in the highest quartile of MVPA at age 5 yr had 4%-14% more BMC at ages 8 and 11 yr than those in the lowest quartile of MVPA at age 5 yr (P < 0.05). CONCLUSIONS: These results provide support for the benefits of early MVPA on sustained bone health during childhood especially for boys. Results indicate the importance of increasing MVPA as a strategy to improve BMC later in childhood.
AB - PURPOSE: This study examined the potential effect of early childhood moderate and vigorous physical activity (MVPA) on later bone health. METHODS: Three hundred and thirty-three children, participating in the Iowa Bone Development Study, were studied at ages 5, 8, and 11 yr. MVPA (min•d -1) was measured using an accelerometry-based physical activity monitor. Bone mineral content (BMC; g) of the whole body, lumbar spine, and hip was measured using dual-energy X-ray absorptiometry. Mixed regression models were used to test whether MVPA at age 5 yr had an effect on BMC at ages 8 and 11 yr after adjustment for concurrent height, weight, age, maturity, and MVPA. The analysis was repeated to control for bone outcomes at age 5 yr. Mixed-model least-squares mean values at the person level of covariates for age group were used to compare the BMC at ages 8 and 11 yr of children in the highest and lowest quartiles of MVPA at age 5 yr. RESULTS: For boys and girls, MVPA at age 5 yr predicted BMC adjusted for concurrent height, weight, age, maturity, and MVPA at ages 8 and 11 yr (P < 0.05). When the analysis was repeated to also control for BMC at age 5 yr, the effect of MVPA at age 5 yr was significant for boys but not for girls. Boys and girls in the highest quartile of MVPA at age 5 yr had 4%-14% more BMC at ages 8 and 11 yr than those in the lowest quartile of MVPA at age 5 yr (P < 0.05). CONCLUSIONS: These results provide support for the benefits of early MVPA on sustained bone health during childhood especially for boys. Results indicate the importance of increasing MVPA as a strategy to improve BMC later in childhood.
KW - Accelerometry
KW - Bone mineral content
KW - Children
KW - Dxa
KW - Longitudinal
KW - Skeletal
UR - http://www.scopus.com/inward/record.url?scp=77952503587&partnerID=8YFLogxK
U2 - 10.1249/MSS.0b013e3181c619b2
DO - 10.1249/MSS.0b013e3181c619b2
M3 - Article
C2 - 19997029
AN - SCOPUS:77952503587
VL - 42
SP - 1072
EP - 1078
JO - Medicine and Science in Sports and Exercise
JF - Medicine and Science in Sports and Exercise
SN - 0195-9131
IS - 6
ER -