title: Leisure time physical activity before and during mid-pregnancy and offspring adiposity in mid-childhood.
abstract: BACKGROUND
  Effects of maternal leisure time physical activity (LTPA) on paediatric obesity are unknown. The objective of this study was to examine associations of maternal LTPA with offspring overall and central adiposity in mid-childhood.
  
  
  METHODS
  We analysed data from 802 mother-child dyads from Project Viva, a prospective pre-birth cohort study. Women reported average weekly LTPA before and during mid-pregnancy. At age 7-10 years, we measured fat, truncal fat and lean mass with dual-energy X-ray absorptiometry. Using multivariable linear regression, we examined associations of maternal LTPA with offspring adiposity, adjusting for child age and sex, maternal race/ethnicity, education, age, pre-pregnancy body mass index, marital status and smoking status.
  
  
  RESULTS
  Mean (standard deviation) of LTPA before and during mid-pregnancy were 9.5 (8.1) and 7.1 (7.0) h week(-1) . At mean age 7.8 (0.8) years, childhood fat, truncal fat and lean mass indices were 4.3 (1.8), 1.4 (0.8) and 12.9 (1.4) kg m(-2) . We did not find that higher maternal LTPA was associated with lower child adiposity outcomes. For example, compared with 0-3 h week(-1) of LTPA during mid-pregnancy, children of mothers with +8 h week(-1) had fat mass index 0.07 kg m(-2) (95% confidence interval: -0.22, 0.36). In analyses of within-person LTPA change from before to mid-pregnancy, compared with +2 h week(-1) decrease in LTPA, increased LTPA (2 ± h week(-1) ) was associated with a 0.09 kg m(-2) fat mass index (-0.25, 0.43).
  
  
  CONCLUSIONS
  Contrary to our hypothesis, higher LTPA before and during mid-pregnancy, and the change between them, were not associated with lower adiposity in mid-childhood.
authors: Division of Behavioral Medicine, Department of Pediatrics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA.
authors: K L
authors: KL
authors: Kong
authors: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.|Department of Nutrition, Harvard School of Public Health, Boston, MA, USA.
authors: M W
authors: MW
authors: Gillman
authors: Obesity Prevention Program, Department of Population Medicine, Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, MA, USA.
authors: S L
authors: SL
authors: Rifas-Shiman
authors: Division of Behavioral Medicine, Department of Pediatrics, School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, USA.
authors: X
authors: X
authors: Wen
mesh_terms: D015502:Absorptiometry, Photon; D050154:Adiposity / Q000502:physiology*; D000328:Adult; D015992:Body Mass Index; D002648:Child; D002664:Child Nutritional Physiological Phenomena; D005260:Female; D006801:Humans; D007899:Leisure Activities; D008297:Male; D009035:Mothers; D009043:Motor Activity; D063766:Pediatric Obesity / Q000517:prevention & control*; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies
keywords: adiposity; childhood obesity; gestation; leisure time physical activity