BBC said the researchers surveyed 1,403 children in two hospitals and hospitals Son Dureta Costa (Spain). These are students from 12 to 17 years are enrolled in 11 schools in northern Spain.
The researchers recommend that children should not carry heavy items over 10% of body weight.
The study authors said children should not carry heavy items over 10% of body weight. Meanwhile, this study found that nearly two thirds of them carry backpacks heavier than 10% of your body weight.
Then the weight of backpacks students were analyzed in relation to back pain. The students were divided into 4 groups based on the weight of my backpack.
Accordingly, the risk of back pain in the students in the group with the heaviest bag is greater than 50% of students in the group carrying the lightest backpacks.
The report stresses that back pain is a growing problem in girls and this risk increases with age.
The study authors said: "The results say a lot. Many children have brought too much heavy backpacks, the overload can not even allow those workers to work".
Sean McDougal in Backcare Charity said: "On average, children in Britain are carrying the heavy bag 15-20% of your body weight. They also often have a habit of carrying a shoulder bag." Sean McDougal advised you should only bring the needed items and make sure to wear a bag or backpack shoulder on both sides.
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