Researchers identify the maximum weight that children should carry in their school backpacks, suggesting that school children who use backpacks should avoid loads of more than 10% of their body weight, and those who use trolleys, 20% of their body weight.

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Researchers identify the maximum weight that children should carry in their school backpacks, suggesting that school children who use backpacks should avoid loads of more than 10% of their body weight, and those who use trolleys, 20% of their body weight.