Promote the burden
For children's schoolbag "burden" has always been the topic of public concern, you know that the most appropriate schoolbags? "Life" magazine, an article in the United States, said that backpack weight should not exceed 10% of the weight of the knapsack.
The American Institute of Physical Therapy has shown a study of 9-grade students, which can cause back injury and muscle fatigue in adolescents with overweight backpacks and faulty backpack.
Researchers Mary Ann Wilmarth said that overweight children will cause kyphosis, scoliosis, tilt or distortion.
At the same time, muscles may be fatigued with extreme tension, and the neck, shoulders and back are vulnerable. If the schoolbag weighs more than 10%-15% of the weight of the knapsack, the damage to the body will multiply. Therefore, she suggested that the backpack weight should be controlled below 10% of the backpack weight.
The American Institute of Physical Therapy recommends that children try to use double-shoulder backpacks. Experts say the double-shoulder way can disperse the weight of backpacks, thereby reducing the likelihood of distortion in the shape.
In addition the tie rod Schoolbag is a good choice for the younger students, because the high grade students in the United States need to change the classroom frequently and downstairs, while the junior students do not have these troubles.
In addition, the reasonable placement of the bag is also important, the heaviest items placed in close to the back position.