title: Growth in bone and body size among Asian and white girls in the Female Adolescent Maturation (FAM) study.
abstract: BACKGROUND
  This study intends to identify differences in growth of Asian and White girls.
  
  
  RESULTS
  Asian girls gained bone at similar rates to White girls. Physical activity was important to bone growth. Ethnic differences remained after adjusting for physical activity, demographics, and diet.
  
  
  CONCLUSIONS
  Physical activity can improve bone gain.
  
  
  OBJECTIVE
  The purpose of this study is to examine differences in body size and bone growth of Asian, White, and Asian-White Mixed girls.
  
  
  METHODS
  Three prospective examinations of 99 Asian, 73 White, and 63 Mixed Asian and White girls, with a mean age of 11.0 years at enrollment were performed. Calcaneal bone mass, skeletal breadths, and body fat were measured. Physical activity, diet, and birth size were reported. The analyses examined the extent that body dimensions and bone size changed over time by demographic, diet, physical activity, body, and bone size parameters.
  
  
  RESULTS
  White children were the most physically active yet had lower calcaneal ultrasound values for speed of sound (SOS). Based on regression models, bone mass, and subscapular skinfold thickness were greater in Asian girls compared to White and Asian-White Mixed girls at age 10 years. Asian-White Mixed girls had greater BMI compared to Asian or White girls. Asian girls gained body size more slowly than White girls, but changes in bone parameters did not differ significantly; Asian-White Mixed girls gained abdomen, hip, and weight more slowly than White girls. Among all girls, SOS and broadband ultrasound attenuation (BUA) increased significantly by level of physical activity before 12 years, but not after.
  
  
  CONCLUSIONS
  Asian girls had more upper body (subscapular) fat at age 10 years and gained height and hip and abdomen circumferences more slowly than Asian-White and White girls. Asian girls had greater bone SOS and BUA at age 10 years but gained bone at similar rates to White girls. Physical activity was especially important to bone growth before age 12 years. However, ethnic differences remained after adjusting for physical activity, demographic, and dietary factors.
authors.affiliation: University of Hawaii at Manoa, 1955 East West Road, Honolulu, HI, 96822, USA. novotny@hawaii.edu.
authors.forename: Rachel
authors.initials: R
authors.lastname: Novotny
authors.affiliation: University of Hawaii at Manoa, 1955 East West Road, Honolulu, HI, 96822, USA.
authors.forename: James
authors.initials: J
authors.lastname: Davis
mesh_terms: D000273:Adipose Tissue / Q000254:growth & development; D000293:Adolescent; D000375:Aging / Q000208:ethnology; D000886:Anthropometry; D044466:Asian People / Q000706:statistics & numerical data*; D049628:Body Size / Q000502:physiology*; D001835:Body Weight / Q000502:physiology; D015519:Bone Density; D001846:Bone Development / Q000502:physiology*; D002111:Calcaneus / Q000000981:diagnostic imaging; D002648:Child; D002664:Child Nutritional Physiological Phenomena / Q000208:ethnology*; D002675:Child, Preschool; D004032:Diet / Q000208:ethnology; D005247:Feeding Behavior / Q000208:ethnology; D005260:Female; D006801:Humans; D009043:Motor Activity / Q000502:physiology; D011446:Prospective Studies; D014463:Ultrasonography; D044465:White People / Q000706:statistics & numerical data*
keywords: Adolescent; Anthropometry; Bone; Child; Ethnicity