Why it is better not to use a cell phone while walking | Technology

He Skilled It has become a kind of afterthought for us all to go out into the street, and it is easy to conclude by looking at the people we pass. Because, although the cell phone is sometimes hidden in a bag or pocket, in many cases it is visible in the hands of users who are walking while sending messages, checking social networks or recording themselves. This multi-tasking contributes to accidents (already warned by DGT in 2015 98% of accidents are caused by pedestrian offenders using mobile phones.), has effects on our posture, focus and gait.

First, there is a change in body posture. If we pause the video of the person walking and using the phone at the same time, we will see a bent and slightly raised hand holding the phone and tilting the head. That is, we lose the arm stroke while holding the cell phone, the swing of the arms while walking. “The swing of the arms is important to stabilize the body and improve lateral balance while walking,” says Fernando Ramos, President Spanish Association of Physiotherapists (AEF). This movement of the arms contributes to greater efficiency in walking and the better use of our energy, so stopping it “can reduce stability during walking or result in energetically expensive stabilization strategies such as increasing the activity of the muscles of the trunk or adjusting the width of the step to increase the base of support and limit the greater tendency to lateral deviation created by the use of the device”. Ramos explains. Also, the position of the arm in constant contraction as it has to stay with the body following the movement of the stroke, causes additional tension and we can suffer from shoulder pain.

The position adopted by the leader is also not very appropriate. “This posture is characterized by a forward position of the head, and our cervical spine is pronated,” notes the head of the AEF. Doing this puts the neck and upper back muscles under undue mechanical stress. “To give us an idea, when our neck is straight and aligned with our torso, the head weighs about 6-8 kg in adults, but when we bend our neck, the stress on the neck increases. The cervical region weighs up to 27 kg, which is 50 The first is to maintain cervical curvature of 60 degrees,” explains Ramos.

This change in posture can translate into pain in the craniocervical region and in the shoulder and shoulder girdle region. Head position also tilts downward as we walk forward, “which can increase the variability of sensory signals from the vestibular and/or visual system to control balance during walking,” notes the head of the AEF.

What we see (not).

Another obvious effect of this change in posture when walking has to do with what our eyes see. “Continuously looking at the phone screen while walking can cause visual fatigue,” explains Pilar Serra, professor of physiotherapy at the University of Valencia. This happens when you look at the cell phone while standing and use the cell phone at the same time. Skilled And walking can cause accommodation fatigue or visual stress, meaning that “eyes have increased difficulty focusing from close distances, such as a telephone screen, to distant ones, such as the surrounding environment.” . The expert points out that after focusing on a screen for a long time, the ciliary muscles of the eye get tired. “It takes longer for our eye muscles to relax and focus at a distance. This will impact the way we adapt to disruptions or unexpected events in the environment,” he points out.

But it's not just that our eyes are fixed on the screen rather than the street: attention is also diverted when we're talking without looking at the screen. In 2010, An interesting study put a clown on a unicycle in the path of passers-by; 75% of those who were talking on their cell phones said they didn't. All of these have an impact on how we walk. “Attention plays an important role in the coordination and control of locomotion,” says Serra. Beyond the risks of tripping and falling or running (crossing the street while looking at your cell phone is fine), “concentrating on a specific task like looking at your phone or reading can cause changes. Your own walking pattern; “a less fluid gait with shorter or more irregular and unsteady steps. It can result.” That is, all these postural changes seen in the still photo are inadvertently added, also observed in the way we walk when we press play.

Slow, short and wide steps

Research on how cell phone use while walking affects this gait pattern is not new. In 2012, when mobile broadband penetration was still around 50%, it was published in the journal Walk and Posture A study With a very clear title: Mobile phones are changing the way we walk. as? Walking and texting speeds were reduced by 33% (and walking and talking on the phone by 16%); In addition to incremental deviation (participants must move toward a target). Other studies They decided that the steps could be shorter or wider (to better maintain balance).

“Human walking is designed to be energy efficient,” says Pilar Serra. “Our body uses movement patterns and a specific sequence of muscle contractions to reduce energy expenditure during locomotion. But if we change it, carry weight while walking, for example, or focus our attention on other tasks, we change it without realizing it,” he says.

It was also investigated whether it matters what exactly we are doing with the mobile phone while we are walking and the results show that: the higher cognitive load of the activity we perform on the phone (writing, reading something simple or complex, etc.), And our parade will be modified. In addition, we are a bit slower when reacting to various stimuli or unexpected events. “By focusing on something else, situational awareness related to the environment can be reduced. This can cause a slow response to changes in the landscape or the need to adjust gear in unexpected situations, on the other hand, this is very common in a city full of pedestrians and motorized or non-motorized vehicles,” Serra explains.

None of these changes would matter much if there were no consequences like pain on the one hand and accidents on the other. “The use of mobile phones while walking significantly increases the risk of falls or accidents in an urban environment, 7% of accidents are related to the use of mobile phones and more than 50% of people are alerted to bumping into something. Or when someone is using their cell phone,” says Fernando Ramos from AEF.

And, as if all this wasn't enough, using a mobile phone at the same time as the walk dilutes many of the benefits of walking. “Cell phone use while walking increases the stress-related hormone cortisol, negatively affecting our mood and reducing the positive effects of walking to be physically active and healthy,” says Ramos.

The solution is clear: forget your cell phone so we don't walk zombies (In Skilled + zombie), a German-born neologism (which was the word of the year in 2015) referring to people who walk at once. “Be careful when walking and limit the use of your mobile phone when moving,” concludes Pilar Serra. It is not necessary to leave it at home; Just don't take it out of your bag or pocket while walking.

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