Your child comes home from school, finishes homework, and reaches for the tablet. You wonder: how much screen time is really too much? A recent study from Croatia gives us some concrete answers that should matter to every Singapore parent.
Researchers tracked over 300 children around age 10 and measured their cardiorespiratory fitness—essentially, how well their hearts and lungs work during exercise. They tested this using a simple shuttle run test, then compared results against how much time children spent on screens (phones, tablets, computers, TV) and how physically active they were overall.
What the Research Found
The key discovery: children who spent a lot of time on screens had noticeably weaker heart and lung fitness compared to peers with low or moderate screen time. This remained true even after researchers accounted for how much physical activity the children did. In other words, a child who exercises regularly but also screens heavily will still have lower fitness than an equally active child who screens less.
But here's the twist that surprised the researchers: this effect isn't equal between boys and girls. Boys showed a clear drop in fitness as screen time increased. Girls, however, showed no significant connection between screen time and fitness levels. Scientists aren't yet certain why, but the pattern was unmistakable across the study.
What This Means for Singapore Families
In Singapore, screen time isn't going anywhere. Our children grow up in a hyper-connected world where devices are essential for learning and socialising. This study doesn't tell us screens are evil—but it does reveal an uncomfortable truth: sitting in front of screens affects our children's developing bodies in ways that simply moving around can't fully fix.
For parents of boys especially, this research is a wake-up call. The traditional approach—"as long as they exercise, screen time is fine"—appears incomplete. A boy who plays football for an hour but then spends three hours gaming is in a different fitness position than a boy who exercises the same amount but screens less.
In our competitive, exam-focused culture, many parents see screen time as educational downtime—a reward after tuition or revision. But this research suggests we might need to rethink that calculus, particularly for sons. The heart and lung development happening right now, in primary school years, sets the foundation for lifelong health.
The study was conducted in Croatia with similar climate and lifestyle factors to parts of Asia, making the findings reasonably relevant to Singapore families. Our children face similar screen pressures and physical activity challenges.
Three Things You Can Do Today
- Set a screen time "budget" separate from activity targets. Don't think "my child exercises, so screens are okay." Instead, treat screen time and exercise as two different health behaviours. Aim for no more than 1–2 hours of recreational screen time on school days, regardless of how active your child is. This is especially important for boys.
- Make fitness fun and screen-free. Instead of using screens as a reward, use movement as one. Invite your child to play badminton, swim, cycle, or join a sport they genuinely enjoy. Make it a family activity so it feels like bonding, not punishment. The goal is building this habit early, when their bodies are most adaptable.
- Create screen-free zones and times. Establish device-free periods—perhaps during dinner, before bed, or the first hour after school. Make these non-negotiable family norms rather than rules you enforce. When screens aren't an option, children naturally find other activities, and their cardiovascular systems benefit.
Your child's heart and lungs are developing right now. Small choices today compound into lifelong health patterns. This research gives us permission to be more intentional about screen time—not out of fear, but out of genuine care for the bodies our children will carry into adulthood.