Interrupting Prolonged Sitting With ACTivity (InPACT) at Home Optimization Study

Experimental protocol: In Stage 1 of the intervention, 30 child participants will enroll in a home exercise program called InPACT at Home. The objective is for each participant to complete three 8-minute exercise videos per day, five days a week (30-45 minutes total daily). Participants will receive a calendar with links to the daily videos on a private YouTube channel. The response rate will be evaluated at the end of week 4, consistent with the original InPACT at Home pilot feasibility trial timeframe. Participants who do not complete Stage 1 will still be eligible to participate in Stage 2, focusing on adherence. Stage 2 involves ten participants continuing with InPACT at Home, while the remaining 20 will be randomly assigned to additional support groups. These groups include daily text message reminders (pings) for ten participants and personalized activity calendars based on individual physical activity preferences for the other ten. The response rate will again be assessed at the end of week 8. In Stage 3, seven participants initially assigned to InPACT at Home + Pings will be randomly reassigned to receive further support through either Tailoring (Condition A) or Coaching (Condition B). Similarly, seven participants initially assigned to InPACT at Home + Tailoring will be re-randomized to receive additional support via either Pings (Condition D) or Coaching (Condition E). Seven participants initially receiving no support will be re-randomized to receive either Pings (Condition G) or Tailoring (Condition H). The primary objective of this pilot project is to assess the feasibility of the study design, ensuring that the response rate does not influence randomization. The study duration is 60 days.

Intervention Components: The InPACT at Home intervention consists of a structured calendar of activities and high-quality exercise videos. Additional supports include personalization of the activity calendar to individual preferences, daily text message reminders to parents, and coaching sessions aimed at overcoming household barriers to participation. Previous research has validated the feasibility of InPACT at Home, while other studies support the effectiveness of the chosen support mechanisms.

Measurements: Consented participants will undergo pre- and post-intervention assessments including physical activity enjoyment, habitual physical activity levels, anxiety and depression symptoms, emotion regulation, and parent support for physical activity. These measures will inform a larger SMART study evaluating the impact of InPACT at Home on child social-emotional health.

Measurement Tools:

• Physical Activity Enjoyment Scale: A validated questionnaire assessing enjoyment during physical activity.
• Physical Activity Questionnaire for Children (PAQ-C): Assesses pre- and post-intervention physical activity levels.
• Patient Health Questionnaire-9 (PHQ-9) and General Anxiety Disorder-7 (GAD-7): Measure depression and anxiety symptoms, respectively.
• Difficulties in Emotion Regulation Scale-Short Form: Evaluates emotion regulation abilities.
• Parental Support of Physical Activity Questionnaire: Assesses parental support for child physical activity.
• Ratings of Perceived Exertion Scale: Measures perceived exertion during exercise sessions using a 10-point scale.

Measurements taken during the Experimental Conditions:

Feasibility will be determined by attrition rates and adherence to the intervention. Attrition will track participants who drop out, while dose will monitor those completing at least 40 of the 60 exercise videos. Video completion will be recorded on activity calendars signed off by parents, and view duration will be assessed using YouTube analytics. Objective physical activity data will be collected using FitBit monitors worn during activity breaks.

Statistical Considerations: Sample size for this pilot study is based on current budgetary constraints (n=30). Data from this study will generate pilot data to calculate effect sizes for a larger trial examining adherence and program effectiveness.

Inclusion criteria

This study will include both males and females aged 8 to 12 years and their parent/guardian from various locations in Michigan. The investigators have chosen this age group because this is a critical age with physical activity participation declines (75% from the age of 9 to 15 years). To be included in the study, participants must:

• Have access to a computer and internet at home.
• Be proficient in English.

Exclusion criteria

Children will not be eligible for the study if they meet any of the following conditions:

• Currently taking medications (e.g., iron, metformin, chemotherapeutic agents) that could impact their ability to engage in physical activity.
• Previously diagnosed with conditions that could impact their ability to engage in physical exercise (e.g., uncontrolled asthma).
• Answering "YES" to any question on the Physical Activity Readiness Questionnaire (PAR-Q)22 indicating the participant has a heart condition, high BP, experienced chest pains or dizziness during daily activities, or require a doctor's recommendation for supervision during exercise.
• Diagnosed with a physical or mental disability that would make it difficult to answer questions or follow directions without the help of an adult.
• Parent or caregiver has a physical or mental disability that would make it difficult for them to answer questions or assist their child with project-related activities, such as completing questionnaires in the laboratory.
• Potential participants who are ineligible will be told so on their screening call and will not be enrolled.