Does Physical Activity Help Children with Obesity? Evidence and Effects
- Participating in physical activity may help children with obesity to reduce their body mass index slightly, but researchers remain very uncertain about the overall effects on weight, body...
- Childhood obesity has grown substantially on a global scale since 1975.
- To understand whether movement helps mitigate these risks, researchers examined studies comparing physical activity programs lasting at least 12 weeks against no physical activity or alternative activity regimens.
Participating in physical activity may help children with obesity to reduce their body mass index slightly, but researchers remain very uncertain about the overall effects on weight, body fat, and metabolic health, according to an evaluation current to December 2025.
A Global Health Crisis Meets Scientific Uncertainty
Childhood obesity has grown substantially on a global scale since 1975. Projections indicate that more than 300 million children and adolescents aged 10 to 19 may live with the condition by 2050. Excess body fat during childhood raises the risk of developing numerous health problems later in life. These include heart disease, stroke, type 2 diabetes, liver disease, asthma, and joint issues, alongside links to higher rates of anxiety and depression.
Evaluating Movement Programs Across Three Nations
To understand whether movement helps mitigate these risks, researchers examined studies comparing physical activity programs lasting at least 12 weeks against no physical activity or alternative activity regimens. Lifestyle modifications such as healthier eating and movement—including running games or interactive video games that encourage physical exertion, sometimes termed exergaming—form the primary approach to managing weight in children.
The review identified four small studies encompassing a total of 517 children with an average age of nine years, with girls accounting for 46 percent of participants. Programs typically lasted 12 to 13 weeks, though one study maintained an intervention for 32 weeks across research sites in Brazil, Iran, and the United States. In the American cohorts, 73 percent of the participants were Black, while other trials did not document participant ethnicities.
Modest BMI Drops and Unexpected Side Effects
When evaluating physical activity against no intervention, data from two studies involving 118 children indicated that active groups may have slightly reduced their BMI, showing an average drop of 1.52 kg/m2.
However, evidence from one trial involving 222 participants suggested that children in active programs were about 3.5 times more likely to experience minor unwanted effects.
Lingering Questions Over Metabolic Health and Data Gaps
Researchers stressed a high degree of uncertainty regarding these outcomes.
Current data does not clarify whether physical activity alters a child’s BMI z-score, total weight, well-being, body fat percentage, body fat distribution, or blood sugar levels, nor does it establish the frequency of serious unwanted events. Furthermore, comparing different types of physical activity—such as exergaming versus pool exercises—or comparing 20 minutes versus 40 minutes of identical activity yielded results with very low certainty.
Methodological Flaws Demand Rigorous Future Trials
Confidence in the existing evidence remains limited due to several methodological constraints across the literature.
The available studies involved small participant pools, utilized widely varying types of physical activity, and exhibited poor reporting of study methods and findings, with three out of four trials failing to report all results. Consequently, larger, longer-lasting, and higher-quality studies are required to determine the true effects of physical activity on children with obesity.