Background:The lack of physical activity and increasing time spent in sedentary behaviours during childhood place importance on developing low cost,easy-to-implement school-based interventions to increase physical activity among children. The PREVIENE Project will evaluate the effectiveness of five innovative, simple, and feasible interventions(active commuting to school, Physical Education lessons, active school recess physical activity, sleep health promotion, and an integrated program incorporating all 4 interventions) to improve physical activity, fitness, anthropometry, sleep health, academic achievement,and health-related quality of life in primary school children.

Methods:A total of 350 children (grade 3; 8-9 years of age) from six schools in Granada (Spain) will be enrolled in one of the 8-week interventions (one intervention per school; 50 children per school) or a control group (no intervention school; 50 children). Outcomes will include physical activity (measured by accelerometry), physical fitness (assessed using the ALPHA fitness battery), anthropometry (height, weight and waist circumference), sleep health (measured by accelerometers, a sleep diary, and sleep health questionnaires), academic achievement (grades from the official school's records), and health-related quality of life (child and parental questionnaires).To assess the effectiveness of the different interventions on objectively measured PA and the other outcomes, the generalized linear model will be used.

Discussion: The PREVIENE Project will provide the information about the effectiveness and implementation of different school-based interventions for physical activity promotion in primary schoolchildren.

Keywords:children, physical activity, school,active commuting, Physical Education, school recess, sleep health, fitness, academic achievement, health-related quality of life.

Background

The lack of physical activity and increasing time spent in sedentary behaviours during childhood place importance on developing low cost,easy-to-implement school-based interventions to increase physical activity among children. The PREVIENE Project will evaluate the effectiveness of five innovative, simple, and feasible interventions (active commuting to school, Physical Education lessons, active school recess physical activity, sleep health promotion, and an integrated program incorporating all 4 interventions) to improve physical activity, fitness, anthropometry, sleep health, academic achievement,and health-related quality of life in primary school children.

Methods

The PREVIENE Project uses a quasi-experimental approach with a convenience sample size of 300 children (grade 3, 8-9 years old) from six primary schools in Granada (Spain) (2 classes per school x 6 schools = 12classesin total). With the average class size of 25 children and the expected recruitment rate is 90%, two classes will be selected in each participating school. All 79 primary schools in Granada will be invited to participate in this study. The schools will initially be contacted by email followed by a phone call. Research team will arrange a meeting with the interested schools and their staff (principal, physical education teacher and other relevant teachers). At this meeting, the researchers will explain the main objective of this study and the inclusion criteria for schools' participation: 1) At least 2 classes of grade 3 children at school, 2) the average class size has to be 25 or more children. Once determined the schools that satisfy the inclusion criteria and express their willingness to participate, a total of six schools will be randomly selected.

The Regional Ministry of Education will endorse the participation of each selected school in the study. At the beginning of the study, families of all children in the selected classes will receive an invitation to an initial meeting at school to receive information about the study. Both children and parents will be encouraged to participate in the study. Parents will sign an informed consent which include the participation of them and their child. The study protocol has been approved by the University of Granada Human Research EthicsCommittee (Reference: 57/CEIH/2015).

Five schools will be randomly assigned to an intervention schools, four of them will apply a single intervention (n=50 children per intervention/school) and one school will implement the integrated program (all four interventions simultaneously;n=50 children).The sixth school will serve as a control school and will not receive any intervention (n=50 children). In schools assigned to the active PE lesson and integrated intervention, standard PE lessons will be replaced for the Active Didactics Unit. In all other schools, children will be exposed to the usual PE session's structure according to the National Education Program in Spain (i.e. 45 min sessions twice per week).

Interventions

Active commuting to/from school

This intervention will include a range of school-, family- and community-based activities. These activities will be focused on children and their families following the ecological model proposed by Sallis et al., targeting mainly individual factors such as children's perceptions (safety perception on the way to school) and attitudes (independence or motivation to walk). A total of six 1-hour activities will be conducted at the classroom and two activities in the school neighborhood designed based on previous literature. Taken together, these activities will emphasize the benefits of active commuting to/from school and promote active commuting to/from school using phrases such as "If you rides a bike for 1.200 km, the medium number of disease days will be reduced by one" for families.Moreover, supporting information will be sent to families on four occasions during the intervention to encourage families to use active modes of commuting to/from school. The supporting information will consist of sending messages by whatsapp and advices (text and images) explaining the most important ideas related active commuting and benefits of active commuting on academic achievements and children´s mental and physical health.

Finally, throughout the intervention period, the teacher will ask children their mode of transport to school of that day twice a week by raising their hand and encourage possible changes in mode of commuting as motivational strategy by using positive reinforcement (as reinforce when some children accompanied each other in the way to school). The objective of this reinforcement is to remind children to active commute to and from school.

Active PE lessons

This intervention has been developed by the Spanish Ministry of Health, Social Services and Equality and the Ministry of Education, Culture and Sport to increase the amount of children's PA during PE lessons in primary schools. At the time of this study, any school in Spain could choose to adopt this programme. This intervention includes two sets of eight active PE lessons specifically developed for third grade of primary school. These lessons will replace the original PE lessons in schools assigned to Active PE lesson intervention and integrated intervention. Additionally, this intervention provides some methodological advices to increase the PA time during the PE lesson (i.e. different ways to take attendance or deciding on the most suitable activity given the availability of resources).

Active school recess

This intervention has been designed based on previous research. The teacher will prepare the school playground offering adequate space and games to encourage children to be active. A sheet placed on the wall as a reminder will help teacher to remind children to participate and motivate them. On this sheet, each child will write the activity completed during the school recess every day during the intervention period.

Sleep health promotion

This intervention will aim to raise the awareness of the importance of having a good quality sleep at night and to teach healthy sleep behaviours that will contribute to improving sleep hygiene. As a part of this intervention, eight activities will be carried out at home and at school. During the first activity, parents and children will attend a general talk about sleep and health and will sign a contract for a "healthy sleep at home". Signing "the contract" will enable participants to have an active role in the sleep intervention. Also, with help of their parents at home, children will complete a diary in which they will keep a record of their activities prior to going to bed and after waking up in the morning. The objective of this activity is to strengthen the importance of a routine before going to sleep and its benefits on the adequate sleep behaviour. Parents will be given a manual to help children use an adequate sleep routine and reinforce children's achievements. At school, several teachers assisted by the researchers will implement the activities. The first classroom-based activity will be based on the educational program "I have a dream" (Spanish adaptation of the SimplyHealthy@Schools International Program; Philips Ibérica, S.A., Madrid, Spain). The remaining classroom-based activities will include with a group art project with questions and answers about sleep, children's calculation of their own sleep parameters from the sleep log data, and discussion groups about the sleep diary completed at home and other sleep issues, as well as strategies to achieve the commitments included in the "signed contract". In addition, the class teacher will introduce the concept of relaxation and its benefits at bedtime and will teach an abbreviated version of the Jacobson's progressive relaxation technique every morning after the recess.

School global intervention

Also, a simultaneous implementation of all four interventions (see the others arms) will be examined in one of the intervention schools.

Data analysis

Demographic characteristics will be analysed using descriptive statistics. Data will be presented using the mean and standard deviation or median and interquartile range, where appropriate for continuous variables, and frequency and percentage for categorical variables. To assess the effectiveness of the different interventions on objectively measured PA and the other outcomes, the generalized linear model will be used with the outcome measures as dependent variables in separate models, the intervention as an independent variable and controlling for potential confounders (such as gender, body mass index, socioeconomic status, and baseline PA). Statistical significance will be set at p<0.05.

Inclusion Criteria:

• Schools with at least two groups of students
• Each group with at least 25 students

Exclusion Criteria:

• None