Children who spend more than three-quarters of their time engaging in
sedentary behaviour, such as watching TV and sitting at computers, have
up to nine times poorer motor coordination than their more active peers,
reveals a study published in the American
Journal of Human Biology.
The study, involving Portuguese children, found that physical activity
alone was not enough to overcome the negative effect of sedentary
behaviour on basic motor coordination skills such as walking, throwing
or catching, which are considered the building blocks of more complex
movements.
“Childhood is a critical time for the development of motor coordination
skills which are essential for health and well-being,” said lead author
Dr Luis Lopes, from the University of Minho. “We know that sedentary
lifestyles have a negative effect on these skills and are associated
with decreased fitness, lower self-esteem, decreased academic
achievement and increased obesity.”
Dr Lopes’ team studied 110 girls and 103 boys aged nine to ten from 13
urban elementary schools. The children’s sedentary behaviour and
physical activity were objectively measured with accelerometers (a small
device that children attach to their waist that quantifies movement
counts and intensities) over five consecutive days. Motor coordination
was evaluated with the KTK test (Körperkoordination Test für Kinder),
which includes balance, jumping laterally, hopping on one leg over an
obstacle and shifting platforms.
The tests were supplemented with a questionnaire for parents to assess
health variables, before the authors compiled the results into three
models to calculate odd ratios for predicting motor coordination. These
were adjusted for physical activity and accelerometer wear time, waist
to height ratio and home variables.
On average the children spent 75.6% of their time being sedentary, but
the impact on motor coordination was found to be greater on boys than
girls.
Girls who spent 77.3% or more of their time being sedentary were 4 to 5
times less likely to have normal motor coordination than more active
girls. However, boys who were sedentary for more than 76% of their time
were between 5 to 9 times less likely to have good or normal motor
coordination than their active peers.
“It is very clear from our study that a high level of sedentary
behaviour is an independent predictor of low motor coordination,
regardless of physical activity levels and other key factors” said
Lopes. “High sedentary behaviour had a significant impact on the
children’s motor coordination, with boys being more adversely affected
than girls."
Until now there has been little research into the links between
sedentary behaviour and motor coordination, but these findings reveal
that physical activity did not counteract the negative effects that high
levels of sedentary behaviour had on motor coordination.
“The results demonstrate the importance of setting a maximum time for
sedentary behaviour, while encouraging children to increase their amount
of physical activity,” concluded Lopes. “We hope that our findings will
make a valuable contribution to the debate on child health and encourage
future investigations on this subject.”
