Physical activity, nutrition, screen time and sleep associated with body weight and physical condition in young children A pilot study of a cross-border project

The aim of this cross-sectional study was to explore the possible relationship between (un) healthy behaviour and (over) weight and physical condition in families with young children (4-7 years), in a village (30,000 inhabitants) in the eastern part of the Netherlands, close to Germany. It is one of two pilot studies as a precursor of a cross-border project, including six Dutch and six German villages, to counteract physical inactivity and possible future metabolic problems. In total, 459 children of five elementary schools and their parents were included. Parents were requested to fill in a questionnaire on the nutritional, physical, sedentary, and sleeping behaviour of their child. Relevant background characteristics were obtained and lifestyle classifications were made. At school, the children's height and weight (body mass index (BMI)) were measured, as well as their physical condition (two tests) and basic motor abilities (four physical exercise tests). The relationship between the standardized BMI z-scores and physical condition test scores, and nutritional, physical, sedentary and sleeping habits was analysed using independent sample t-test, bivariate correlation analysis and multiple regression analysis. Latent class analysis was used to identify clusters of people based on their nutritional, physical and sleep habits. Of the parents, 376 (82 %) were willing to fill out the questionnaire. High birth weight and a high BMI of the mother and/or father correlated with a higher BMI of the child (p = 0.28, p < 0.001; p=0.13, p = 0.016; and p = 0.23, p < 0.001, respectively). Daily playing outside, eating small cookies (compared with large cookies) and no sleeping problems (no waking up during the night) were related to low BMI levels (no overweight) [p = -0.14, p = 0.005; p = -0.12, p = .020; t(364) = 1.81, p = 0.072 (trend), respectively]. Daily playing outside (frequency and duration) and being a member of a sports club were related to positive scores on the physical condition tests [p = 0.20, p < 0.001; t(365) = -2.99, p = 0.003, respectively]. High levels of television (TV) watching and general sleeping problems were related to a less optimal physical condition [p = -0.09, p = 0.076 (trend); and p = -0.10, p = 0.059 (trend), respectively]. A latent class analysis revealed three clusters: 46 % of the sample belonged to the 'healthy group' concerning nutrition, sedentary lifestyle and TV/personal computer (PC) use; 17 % to the 'less healthy' group; and 37 % to a group with nutrition and physical activity habits close to the healthy group, but with low conditional probabilities for the sleeping items. Conducting a pilot study before the start of a binational intervention study gives a blueprint for the final questionnaire, and clues for tailored interventions in the schools, as proposed in the approach of 'Gesunde Kinder in gesunden Kommunen' (GKGK). The results of a latent class analysis underscore that interventions should exist of a multi-component strategy, focusing on promoting physical activity, healthy nutrition habits and appropriate sleep.