Freshly-graduated physiotherapist Andrea Damato explains to Ramona Depares that heavy schoolbags need not lead to pain and problems.
How much is too much for a child to carry? What is good bag weight to body weight proportion?
Studies abroad have shown that anything exceeding 10 per cent of the child’s body weight induces postural changes during gait patterns, that is the way a child bends the trunk forward to make up for the weight of the bag. For example, a child weighing 30kg shouldn’t carry more than 3kg on his bag.
What are the dangers of overly heavy school bags?
The topic has been the subject of much research, and there are different interpretations of results. However, some studies have shown that the long-term effects of overly heavy school bags caused back and shoulder pain in children carrying 15 per cent to 20 per cent of their body weight. As explained above, heavy bags do cause bad posture when carried for a prolonged period of time, as in the case of younger children. However, there is no significant evidence to show that a structural, spinal deformity can result.
Slouching forward while carrying a heavy bag makes breathing harder, and can lead to poorer lung function.
Anything exceeding 10 per cent of the child’s body weight induces postural changes
Is there a right way and a wrong way to carry a heavy school bag?
Carrying a bag on one shoulder, using just one strap, pushes all the weight of the bag to that shoulder, leading to a sideways deviation of the spine and asymmetric load on the shoulders. Although there are no studies that denote long-term effects, it has been shown that this way of carrying a school bag caused more back pain when compared to other techniques.
Carrying the bag on two straps is the best way to distribute the weight. However, one must also keep in mind the length of the straps. The ideal position of a bag is just below the line of the shoulders, with the bottom part of the bag not exceeding the waist line. Therefore, a properly-sized bag should be chosen for the child.
How important is posture?
A good upright posture is usually an indication of good musculoskeletal health. Maintaining an upright posture means that the body’s dynamics work naturally with muscles, with an optimum length and angle to contract, therefore working more efficiently as a whole.
With bad posture, the body spends a lot of energy to keep itself upright. Tight muscles, neck and back pain may be the result of such fatigue on the body, leading to joint stiffness and possible arthritic changes when joints are posed to extreme stresses.
Is it best to use a backpack or does this place too much strain on the back?
A two-strapped backpack is ideal, as long as the 10 per cent bag weight to body weight ratio is not exceeded. This is because the abdominal muscles and the back muscles, which are the strongest in a child’s body, support the full weight of the bag when worn correctly.
What is your advice for correct weight distribution?
Narrow straps in a bag can cause nerve injuries or affect circulation from the neck down to the arms, leading to tingling, numbness or weakness in the arms. Therefore, two wide, padded straps are ideal for correct weight distribution. Sometimes, having a waist strap helps distribute the weight more evenly through the body.
In the bag itself, large books are to be put at the back, closest to the child’s back, while lighter smaller books are to be put at the very front.
Kids tend to spend the whole day at their desk. What posture should they adopt to avoid back problems?
Studying at a desk is tiring, therefore, to reduce the risk of obtaining a bad posture, the lower back should be properly supported, with the backrest at around 100 degrees and not completely upright. If using a monitor, this is to be placed at eye level. The thighs should be fully supported with feet flat on the ground, or on a stool ifnecessary. The keyboard and the mouse should be at the level of the elbows and, if possible, with an arm rest to avoid stress injuries.
What sort of desk chair is best to use at home?
A height-adjustable desk chair with a fully supported back, especially around the lower back, should be chosen. It can also have forearm/elbow support in order to have less stress on shoulder muscles.
Are any particular exercises recommended for kids to ensure the best development of their posture, spine, etc...
Specific exercises can only be given after assessing children with bad posture, as each body is different and unique. However, usually, we suggest that children spend less time in front of computers and desks and adopt a more active lifestyle. When you strengthen the back muscles by engaging in sports and physical activity, you are likely to reduce the risk of obtaining bad posture.
Children should also be told not to slouch forward during lessons, not to rest on one hand and not to let the chin poke forward, especially after long hours of sitting.
Most children also spend a lot of time using touch-screen gadgets. What are the dangers associated with repeated use of thumbs/wrist/neck etc... and how can they be avoided?
The advantage of having a tablet or a smartphone is that this can be carried anywhere. However, this also means that it can be used in any position, including those that are usually not ideal to maintain good posture.
Holding a tablet flat on a desk does not help to maintain good neck posture, while holding it completely upright can lead to wrist nerve injuries. Somewhere in between is best, and usually, a 30-degree to 40-degree angle is advised when typing, and can be put more upright if one is just reading.
When using the touch screen, wrists must be kept straight and relaxed, to reduce stress on wrist muscles. Also ensure that the font size is large enough to avoid getting close to the screen to read properly and be able to read from far enough.
Any other advice you would give to parents?
I would suggest that parents encourage the use of lockers at school whenever possible. Also, do make sure that children only take the necessary books on the day, with the notes they need, to avoid adding on useless weight.