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Smartphones Causing Reduced Physical Activity among Boys


Boys aged 11–13 have reduced their physical activity by a quarter over the last 13 years, according to a study from the University of Gothenburg and Linnaeus University. ‘There may be a smartphone effect,’ says Anders Raustorp, reader at the University of Gothenburg.

While a large number of studies have measured young people’s participation in sports, the new study looks at the total amount of physical activity per day.

Under the leadership of Raustorp, a group of researchers studied the daily physical activity of 40–100 second and third graders at each of five schools on three occasions 2000–2013. Physical activity was recorded during and after school hours using step counters. The children’s heart rate, weight, height and BMI (body mass index) were also measured.

Twenty per cent meet recommended levels

Girls in second grade increased their activity from 2000 to 2006 and then stayed stable throughout the rest of the period. Boys in second grade and girls in fifth grade displayed steady levels 2000–2013. The boys in fifth grade, however, reduced their activity level by 24 per cent from 16 670 to 12 704 steps per day on average. Only 20 per cent of the boys reach the recommended 15 000 steps per day.

‘This finding is problematic. Regular physical activity provides a significant health benefit for children. We also know from previous studies that children who are found to be insufficiently active at age 12 tend to display the same activity pattern as adults,’ says Raustorp.

One consequence of the reduced activity levels is that the share of overweight/obese children increased in three of the four studied groups over the studied period. The only exception was girls in fifth grade, as the share actually decreased in this group. In previous measurements at these schools, the children have displayed relatively high activity levels in an international perspective, and this is still true for second graders and girls in fifth grade. One possible reason for the decline in physical activity among boys in fifth grade, says the research team, is the increased access to smartphones.

Absorbed by smartphones

‘We looked for something that may have influenced the activity levels after 2006–2008 in fifth grade but not in second grade and that affects boys more than girls. Structured observations in 2013 focused on the children’s playtime in school. In 2013, all studied boys in fifth grade had access to a smartphone, and it was also mainly the boys who were absorbed by these gadgets during playtime in school,’ says Raustorp.

Read the article in Acta Paediatrica

For more information, please contact Anders Raustorp, reader (docent) in physiotherapy at the Department of Food and Nutrition, and Sport Science, University of Gothenburg:
Telephone: +46 (0)708 11 87 06, email:

Facts: The recommended daily number of steps for children, according to 14 researchers from USA, Australia, Canada, France, Sweden and other countries, is 12 000 for girls and 15 000 for boys. These values correspond to 60 minutes of moderately intense physical activity for both boys and girls in fifth grade. The share of children who met this recommendation decreased over the course of the 13-year study, from 71 to 61 per cent for girls and from 76 to 20 per cent for boys.