BACKGROUND: Chronic constipation is a long-term problem that decreases children's quality of life. Information and communication technology devices have developed rapidly in recent decades and have had various impacts on children. This prospective cohort study examined the association between television/digital versatile disc (TV/DVD) screen exposure time at age 1 and the risk of chronic constipation at age 3. METHODS: Data from 63,697 infants in the Japan Environment and Children's Study (JECS) were analyzed. We divided participants into five groups according to TV/DVD exposure time per day: no exposure (0 h), short exposure (<1 h), middle exposure (1.0-<2.0 h), long exposure (2.0-<4.0 h), and very long exposure (≥4 h). Logistic regression analysis was performed to assess the association between TV/DVD exposure time and the risk of constipation. For logistic regression analysis, odds ratios (ORs) were adjusted for sex, parents' education, household income, nursery school, feeding contents, and obesity. The interaction between the sexes was also examined. RESULTS: The prevalence of constipation for males, females, and all participants at age 3 was 9.3, 11.0, and 10.1%, respectively. The TV/DVD screen time distribution per day at age 1 was 10.6% for none, 34.1% for short, 29.9% for middle, 19.2% for long, and 6.2% for the very long exposure group. After adjusting for confounding factors, a dose-response pattern was identified between TV/DVD exposure time and constipation in all participants (p for trend < 0.001). The adjusted ORs increased progressively in the short (OR 1.15, 95% confidence interval [CI] 1.04-1.27), middle (OR 1.22, 95% CI 1.11-1.35), long (OR 1.37, 95% CI 1.24-1.52), and very long exposure groups (OR 1.53, 95% CI 1.35-1.74). This association was not significantly different between the sexes (p for interaction = 0.36). CONCLUSIONS Longer TV/DVD exposure time at age 1 was associated with the risk of chronic constipation at age 3. Excessive screen exposure may need to be avoided from infancy to decrease the risk of chronic constipation in later years.
Humans ; Constipation/etiology* ; Male ; Female ; Japan/epidemiology* ; Television/statistics & numerical data* ; Child, Preschool ; Infant ; Screen Time ; Prospective Studies ; Risk Factors ; Chronic Disease/epidemiology* ; Prevalence

The purpose of this study was to investigate the consciousness among young people (n = 1016) on training body part(s), using a questionnaire-based survey showing participants a picture of a single-joint exercise. The participants were shown a picture of knee-extension exercise (KNEE-EXT), and were asked to identify the body part(s) they felt were being trained. On seeing the picture, more than 90% of the participants felt that KNEE-EXT can train the anterior thigh part. However, more than 90% of the participants who had no experience doing KNEE-EXT felt that the exercise trained not only the anterior thigh part but also other parts, including the trunk, the posterior thigh, and the upper limb. Among those participants who had performed KNEE-EXT without the experience of strength-training under professional supervision, approximately 80% felt that the exercise was appropriate to train not only the anterior thigh but also other parts. These results suggest that performing exercises by referring to only a picture may result in the individuals not properly understanding how the body part(s) should be trained during exercise, even in single-joint exercises. Appropriate supervision is of even greater importance especially for strength-training beginners. Furthermore, even among participants who had an experience of exercise under professional supervision, approximately 60% had a similar response. Therefore, to enhance the benefits of exercises, individuals (even those who have had experience in training under professional supervision) should always be instructed under appropriate supervision on the correct technique and knowledge about the exercises.