Physical activity of pregnant Hispanic women.

BACKGROUND: A growing body of evidence suggests that physical activity during pregnancy can reduce risk of pregnancy complications. However, factors influencing activity in pregnant Hispanic women, who have high rates of sedentary activity as compared to non-Hispanic whites, are not well characterized. PURPOSE: To assess patterns and correlates of physical activity among 1355 participants in Proyecto Buena Salud, a prospective cohort of pregnant Hispanic women in Massachusetts from 2006 to 2011. METHODS: Analyses were conducted in 2012. Pre-, early-, mid-, and late-pregnancy physical activity were assessed using the Pregnancy Physical Activity Questionnaire. Women reported the frequency and duration of household/caregiving, occupational, sports/exercise, and transportation activities and were classified according to compliance with American College of Obstetricians and Gynecologists guidelines for physical activity. RESULTS: Household/caregiving activity was the primary mode of pregnancy activity ranging from 56% to 60% of total activity while sports/exercise contributed the least (<10%). Compared to nulliparous women, women with two or more children were 85% less likely to become inactive at any time during pregnancy (OR=0.15, 95% CI=0.04, 0.56, p-trend <0.01). Women with one or more children increased their total physical activity on average 9.73±2.04 MET-hours/week and 12.04±2.39 MET-hours/week, respectively, with the onset of pregnancy (p<0.01). Those with the highest levels of total physical activity prior to pregnancy were 87% less likely to become inactive with the onset of pregnancy than those who were inactive prior to pregnancy (OR=0.13, 95% CI= 0.05, 0.29). CONCLUSIONS: Findings can inform culturally appropriate interventions designed to reduce pregnancy complications through the promotion of physical activity during pregnancy.

Development of a questionnaire to assess maternal attitudes towards infant growth and milk feeding practices.

BACKGROUND: There is increasing recognition that public health strategies to prevent childhood obesity need to start early in life. Any behavioural interventions need to target maternal attitudes and infant feeding practices, This paper describes the development and preliminary validation of a questionnaire to assess maternal attitudes towards infant growth and milk feeding practices. METHODS: We designed a 57-item (19 questions), self-administered questionnaire to measure the following four domains- 1) type of milk feeding, decision making and sources of advice; 2) frequency and quantity of milk feeds; 3) attitudes to infant feeding and growth; and 4) theory-based beliefs about following infant feeding recommendations. Forty mothers completed the questionnaire on two occasions six days apart (to assess test-retest reliability) and then participated in a semi-structured, open-ended telephone interview covering the same domains (to assess criterion validity). Percentage agreement, Cohen's Kappas (for categorical variables) and Spearman's correlation coefficients (for continuous variables) were used to quantify reliability and validity. Internal consistency between theory-based constructs (self-efficacy, outcome expectancy and intention) was quantified by Chronbach's alpha. RESULTS: Of the 57 questionnaire items 51 (89%) had percentage agreement above 70% indicating good test-retest reliability, and the remaining 6 items had moderate or substantial levels of agreement (kappa 0.41-0.68). Comparing questionnaire with interview coding (validity), percentage agreement was above 66% for 39/57 items (68%). Of the 16 items with percentage agreement below 66%, only five had kappa values below 0.20 (two items had insufficient interview responses). Internal consistency was 0.51, 0.79 and 0.90 for self-efficacy, outcome expectancy and intention respectively. CONCLUSIONS: This questionnaire could be a useful tool in understanding the determinants of infant feeding and the 'causal mechanism' of interventions that target infant feeding practices to prevent early obesity.

An investigation of patterns of children's sedentary and vigorous physical activity throughout the week.

BACKGROUND: Participation in higher intensity activity (i.e. vigorous physical activity [VPA]) appears more consistently associated with lower adiposity, unfortunately little is known about the nature and patterns of VPA participation in children. OBJECTIVE: To examine the volume and patterns of vigorous and sedentary activity during different segments of the week (weekend, school-based and out-of-school). We also investigated differences by sex, socioeconomic status (SES) and weight status. DESIGN: A cross-sectional study including 1568 UK children aged 9-10 years. OUTCOME MEASURES: Sedentary activity (mins), total activity (counts/min) and VPA (mins) were measured by accelerometry. Using a series of 2 level mixed effects linear regression models we tested differences across the segmented week (school time [0900-1500] vs. out-of-school time [0700-0900 & 1500-2100]; and weekday vs. weekend); all models were adjusted for sex, weight status (gender- and age-specific body mass index [BMI] cut points), SES, age and accelerometer registered wear time. RESULTS: Boys and girls accumulated higher VPA out-of-school compared to during school (boys mean ± SD 16.9 ± 9.6 vs 12.6 ± 5.8; girls, 13.1 ± 7.7 vs 8.2 ± 4.0, both p < 0.001); but there were no differences for weekday v weekend VPA (p > 0.05). Less time was spent sedentary on weekdays compared to weekends (p < 0.001). Although boys were more physically active and girls accumulated more sedentary time, the overall pattern in which their physical activity intensity varied across the various day segments was similar when stratified by weight status and SES; and large volumes of sedentary time were observed each hour across the day. CONCLUSIONS: The promotion of VPA during the weekend may hold the greatest promise for increasing VPA. Interventions aimed at increasing physical activity in 9-10 year old children should aim to target all children independent of sex, SES or weight status.

Determinants of early weaning and use of unmodified cow's milk in infants: a systematic review.

Introduction of complementary foods (weaning) before 4 to 6 months of age and unmodified cow's milk before age 12 months are associated with several health risks. To develop effective interventions to discourage these practices, evidence of their determinants is needed. This systematic review identified documents from seven electronic databases (database inception 2008) and reference lists, and by contacting authors. Seventy-eight studies in developed countries, published between 1976 and 2008, quantifying the association between either feeding practice and its potential determinants were included. Study quality was systematically assessed in terms of representativeness, sample size, method of outcome ascertainment, and approach to statistical analysis. The distribution of evidence for each determinant was visualized in a harvest plot showing the strength and direction of associations found and the quality of relevant studies. The strength of evidence for each determinant was summarized as strong, moderate, limited, or inconclusive, using an algorithm based on the consistency of the results of studies of the highest available quality. Strong evidence denoted that the determinant was examined in three or more high-quality studies and >/=75% of results were consistent. Strong evidence was found for six determinants of early weaning (ie, young maternal age, low maternal education, low socioeconomic status, absence or short duration of breastfeeding, maternal smoking, and lack of information or advice from health care providers) and for two determinants of early introduction of unmodified cow's milk (ie, low maternal education and low socioeconomic status). Of these determinants, improving advice given by health care providers appears the most tractable area for intervention in the short term.