An interventional study of Physical Activity Intervention Based on Theory of Planned Behavior in Sedentary Lifestyle, Sedentary Behavior and Physical Activity Level, sponsored by Eskisehir Technical University. Completed at 1 site in Turkey. Open to female participants aged 15 Years to 18 Years, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-05-18.
Sponsored by Eskisehir Technical University · Not applicable, Interventional, and Supportive care
The aim of this study is to examine the effects of a physical activity intervention plan developed based on the theory of planned behavior on the physical activity levels of adolescent girls, their sedentary time and their knowledge about physical activity.
Within the scope of this research, answers to the following research questions will be sought;
In this context, researchers will compare 3 groups within the scope of the data provided by two preliminary studies conducted previously. These groups; (1) intervention group based on the theory of planned behavior, (2) intervention group based on the theory of planned behavior with family participation, (3) control group.
While the physical activity participation of adolescents in Turkey and around the world is quite low, this is more pronounced for girls. The low physical activity participation rates seen in this group shed light on the negative situations to be seen in the future in terms of public health and the economy. The fact that health-related behavior patterns acquired during adolescence form a highly effective basis for the rest of life makes it necessary to develop effective, low-cost physical activity intervention plans for adolescents that take into account individual needs. Research on physical activity intervention, while generally targeting groups with low physical activity levels, is applied in different contexts (school, family, school and family, living environment) where these groups spend their time. In this respect, school-based interventions, where adolescents spend most of their time, come to the fore. For plans to be effective, they should be based on a research process and their theoretical foundations should be inclusive. While the theory of planned behavior, which has an important place in shaping health behaviors and explains the formation and continuity of behavior by addressing the attitude, norms created by the social environment, and the control perceived by the person towards the behavior, constitutes the theoretical basis of this research, the aim of the research is to create and test a school-based physical activity intervention plan based on the theory of planned behavior, targeting adolescent girls.
Qualitative and quantitative research methods were applied through a multi-stage design process, and the findings revealed the need to create an effective intervention plan guide for adolescent girls in Turkish society. These phases included (I) a study to explain which factors are important for physical activity behavior in adolescent girls, including open-ended questions and semi-structured interviews; (II) the process of developing a measurement tool in the light of the data obtained with these qualitative methods; and (III) survey research that adopted the general survey model and reached a large population. As a result of this process, which has been going on for about 48 months, the physical activity intervention plan to be implemented has been shaped. With this intervention, it is aimed to create significant effects among adolescent girls in terms of physical activity and sedentary time and to positively affect their beliefs about physical activity.
The physical activity intervention plan to be developed according to the planned behavior theory will be based on the information obtained in pilot studies that have already been completed. The plan will be implemented in selected high schools affiliated with the Turkish Ministry of National Education. The developed protocol is planned to be implemented over two different time periods. The reason for this is that seasonal factors are emphasized as an important factor in carrying the gains provided in physical activity intervention plans into daily life (Rowland et al., 2006; Tucker \& Gililand, 2007; Belanger et al., 2009; Kornides et al., 2018). The contents of the intervention plan will be delivered to students for 2 hours in selected physical education and sports classes. It is planned to implement this plan in physical education classes for one semester. Considering that the implementation will take place in one academic year, data will be collected at the beginning and end of the first semester and at the end of the second semester. Data collection processes are planned to take approximately 1-1.5 months. Thus, it will be ensured that this application will be carried out for 3-3.5 months in a semester. While planning this period, Owen et al. (2017) reviews and meta-analyses were taken into consideration.
Structurally, the physical activity intervention plan is planned to include four dimensions based on the theory of planned behavior. The first two of these are: (I) transferring information on health-related physical fitness and physical activity; (II) taking individual responsibility for physical activity follow-up; and (II) simple individual planning, which will affect the level of physical activity at the individual level. Another dimension is the inclusion in the program of the types of activities that the female adolescents (III) chose and declared that they would enjoy participating in. The last dimension, as emphasized in the theory of planned behavior, is the invitation of significant others, which are the family, teachers, and other students, including male students, with whom the target group is in constant social interaction, to this plan, and all of the practices are open to them. However, data will not collected from them.
Exclusion Criteria:
Participants in this arm of the experimental group will participate in a school-based intervention program that is based on the theory of planned behavior and includes behavior change techniques. These participants will participate in the intervention plan only in physical education and sports classes at their schools.
Behavioral: Physical Activity Intervention Based on Theory of Planned Behavior
This group will not be involved in any implementation until the end of the research. Ethically, after the research is completed, the proposal to repeat the most effective intervention arm for this group will be presented to the participants in this group.
The content of the intervention plan to be implemented consists of the following components: (I) transferring knowledge about health-related physical fitness and physical activity, (II) taking individual responsibility for physical activity monitoring and simple individual planning, (III) including in the program the types of activities that female adolescents choose and declare that they would enjoy participating in.
Affection for Physical Activity
Affection for Physical Activity is one of the subdomains of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of ten items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 50, and the minimum score is 5. The higher scores obtrained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Social Expectations in Physical Activity
Social Expectations in Physical Activity is one of the subdomains of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of three items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 15, and the minimum score is 3. The higher scores obtained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Health Expectations in Physical Activity
Health Expectations in Physical Activity is one of the subdomains of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of eight items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 40, and the minimum score is 8. The higher scores obtained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Attitutde towards Physical Activity
Attitude towards Physical Activity is a composite score of Affection for Physical Activity, Social Expectations in Physical Activity and Health Expectations in Physical Activity subdimensions of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of twenty-one items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 105, and the minimum score is 21. The higher scores obtained in the subdimension represent higher attitudes.
Time frame: 4 months
Parental Support in Physical Activity
Parental Support in Physical Activity is one of the subdomains of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of three items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 15, and the minimum score is 3. The higher scores obtained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Peer Support in Physical Activity
Peer Support in Physical Activity is one of the subdomains of Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of three items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 15, and the minimum score is 3. The higher scores obtained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Subjective Norms in Physical Activity
Subjective Norms in Physical Activity is a composite score of Parental Support in Physical Activity and Peer Support in Physical Activity, a subdimension of Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of six items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 30, and the minimum score is 6. The higher scores obtained in the subdimension represent higher attitudes.
Time frame: 4 months
Perceived Behavioral Control in Physical Activity
Perceived Behavioral Control in Physical Activity is one of the subdomains of the Physical Activity Belief Questionnaire (PAB-Q). The subscale consisted of five items answered on a 5-point Likert scale. The maximum score that can be obtained from this subscale is 25, and the minimum score is 5. The higher scores obtained in the subdimension represent higher belief in that subscale.
Time frame: 4 months
Body Mass Index (BMI)
Body Mass Index (BMI) is a numerical value derived from an individual's weight and height. The BMI is going to be expressed in units of kg/m² (kilograms per square meter) in the metric system.
Time frame: 4 months
Average kcals per day
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Average kilocalories (kcals) per day refer to the mean energy expenditure related to physical activity over a 24-hour period, as estimated by the wGT3X-BT accelerometer.
Time frame: 4 months
Time in light physical activity
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Time in light physical activity is the duration spent in activities classified as light intensity by the wGT3X-BT accelerometer.
Time frame: 4 months
Tme in moderate to vigorous physical activity
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Time in moderate to vigorous physical activity is the combined duration spent in activities classified as both moderate and vigorous intensity by the wGT3X-BT accelerometer.
Time frame: 4 months
Time in vigorous physical activity
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Time in vigorous physical activity represents the duration spent in activities classified as vigorous intensity by the wGT3X-BT accelerometer.
Time frame: 4 months
Time in moderate physical activity
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Time in moderate physical activity is the duration spent in activities classified as moderate intensity by the wGT3X-BT accelerometer.
Time frame: 4 months
Body Weight
Body weight refers to the mass of an individual's body, and is going to measured by using Tanita BC-601 in kg.
Time frame: 4 months
Body Height
Body weight is a measurement of the vertical distance from the bottom of the feet to the top of the head when a person is standing upright. It is going to be measured by using Leicester Height Measure MK-II in m.
Time frame: 4 months
Activity Kilocalories
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Activity kilocalories (activity kcals), as an outcome measure from a GT3X Link accelerometer, refer to the estimated energy expenditure related to physical activity over a specified time period. The accelerometer, which records acceleration in three dimensions, allows for the assessment of different activity intensities, helping to quantify the amount of energy expended during various activities
Time frame: 4 months
Total Sedentary Bout
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Total sedentary bouts, as an outcome measure from a GT3X Link accelerometer, typically refer to the cumulative duration or count of extended periods of sedentary behavior detected by the accelerometer over a specified time period. Sedentary bouts are intervals during which a person is engaged in minimal or no physical activity, often characterized by activities such as sitting or lying down.
Time frame: 4 months
Average kcals per hour
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Average kilocalories (kcals) per hour represent the mean energy expenditure related to physical activity calculated on an hourly basis using data recorded by the wGT3X-BT accelerometer.
Time frame: 4 months
Total sedentary bouts
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Total sedentary bouts refer to the cumulative count or duration of extended periods of sedentary behavior detected by the wGT3X-BT accelerometer over a specified time period.
Time frame: 4 months
Total sedentary breaks
This outcome measure is going to be measured by Actigraph wGT3X-BT accelerometer. Total sedentary breaks represent the cumulative count of interruptions in sedentary behavior detected by the wGT3X-BT accelerometer over a specified time period.
Time frame: 4 months
Plan to share: No
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Eskisehir Technical University