When you next buy your son or daughter a teddy bear make sure it’s a heavy one.

Researchers at Indiana State University have found that weighted toys helped children to burn calories and boosted heart rates.

With American child obesity levels hitting the roof, it seems that some scientists are suggesting that parents turn to weighted toys to help children build strength, balance, coordination, and generally keep fit.

Professor John Ozmun and graduate student Lee Robbins conducted the study with 7- and 8-year-old children, who carried 3-pound weighted and unweighted cardboard blocks while wearing a portable metabolic unit that measured physiological characteristics.

“We conducted the research project to find out if you changed the weight of a toy, would there be an effect on certain fitness-related characteristics”, said Ozmun, acting associate dean of ISU’s College of Health and Human Performance, and physical education professor. “Our results showed that the extra weight in the blocks could be used to help improve children’s fitness.”

However, some experts have cautioned that children could hurt themselves trying to lift too much too soon, and said more activity is preferable to heavier toys.