Sit-stand workstations in the school classroom: long-term effects on physical (in)activity, sedentary behavior, physical fitness, academic performance, cognition, quality of life, sleep, and stool in primary school children.

Following the advances in technology in the past century, people nowadays spend
the largest part of their waking hours sedentary. Sedentary behavior is
associated with obesity, cardio-vascular diseases, diabetes, and a reduced
cardio-respiratory fitness; not just in adults, but also in children. In
addition, sedentary behavior is associated with reduced self-confidence and
academic under-achievement. Sedentary behavior learned in school continues into
adolescence and adulthood. From childhood onwards, sedentary behavior becomes
the rule rather than the exception: children spend a large part of their waking
hours at school in a classroom that is designed for sitting.
Therefore, the school setting, in particular, is the place to reduce children's
sedentary time and promote standing and active behavior. Given the fact that
the environment has a very strong influence on behavior, sit-stand desks may
invite and seduce children to sit less time and promote standing and active
behavior. Health benefits of reducing sedentary time have been demonstrated in
studies in adults at work and in recent, short-term studies in children. In
these studies the availability of sit-stand desks did reduce sedentary time and
increased energy expenditure while academic performance didn't suffer.
Moreover, it is suggested that academic performance benefits from less sitting
and more standing. Additional advantages of reducing sedentary behavior in the
classroom are better concentration and task focus. However, all these benefits
have only been reported in short-tern studies.

With this study we aim to research whether long-term behavior change can be
induced by changing the school environment: implementing sit-stand desks to
reduce sedentary time in the classroom. In addition, we investigate wether
sedentary time reduction (and increase of standing time and active behavior)
has positive effects on physical fitness, academic achievements and cognitive
skills, body composition, quality of life, sleep and stool. With the results
better advice can be given for health promoting changes in the school
environment.

This is a single-blind, randomized, controlled trial with a baseline assessment
(in June 2017) and repeated measures. These will take place twice each year for
two and a half years: in January and in June (the final assessment will be in
June 2019).
The children and parents will be asked whether the children may be contacted
for another week of activity monitoring seven years after commencement of the
study. If so, then at that moment they will be asked again whether the children
may be contacted for another week of activity monitoring seven years later.
After that, the same procedure is followed one more time. This would mean that
these children will go through three more test weeks after the initial study at
the Lorentzschool until they are around thirty years old.

The children in the intervention group (approximately 28; 8-10 years old) will
receive sit-stand workstations in their classroom. They will keep these for two
and a half years. Their teacher will also receive a sit-stand workstation. The
children are invited and motivated to reduce sedentary time at school. They are
not ordered or obligated to stand more than would normally happen in classrooms
without sit-stand workstations.
The children in the control group (approximately 28; 8-10 years old) will use
regular (sit) workstations and will receive regular treatment.

For the experimental group there are no additional risks with the sit-stand
desks in their classroom compared to the group keeping their regular school
furniture. These sit-stand workstations are easy to handle by children.
For both groups there are no risks involved in testing. Most tests are regular
tests that could have been performed otherwise as well.
Furthermore, there are computer tasks to test cognitive functioning at school
and questionnaires that can be filled in at home. There are no health risks
involved.
It is expected that the activity monitoring will cause the largest burden: a
small device (Activ8 activity tracker) will be taped (Tegaderm, 3M) to the
upper leg for a school week (Monday to Friday). Together with the
parents/carers this process will be monitored. In case skin irritation occurs,
alternative ways to fix the device to the upper leg will be investigated or the
measurements with the device will be stopped.