Activity Breaks for Brain Health in Adolescents
Condition: Healthy Adolescents
Study type: Interventional

Summary: 
      The main aim for this study is to investigate to what extent physical activity of moderate or
      low intensity, relative to prolonged inactivity, may acutely alter neural activity-related
      prefrontal cortex oxygenated hemoglobin during a cognitive demanding task in 13- 15 year-old
      adolescents. The study is primarily focused on investigating these effects in ecologically
      valid conditions, i.e. activity patterns that closely resemble a typical day in school and
      using activity modes that are suitable in a school setting.
    

Detailed description: 
      The study will be a controlled crossover experimental trial with three conditions. Each
      participant will complete each of the three experimental conditions, separated by a washout
      period of minimum four days. Physical activity behaviours and sleep will be monitored the
      day/night before each test day. The first visit will be a familiarization session for the
      collection of demographic data, fitness testing, and acquaintance with experimental
      procedures. On the second, third, and fourth visits, participants will undergo three
      different standardized 80-minutes interventions in a randomized order. Before and immediately
      after the 80-minutes interventions, blood pressure, augmentation index, and cerebral
      hemodynamic response of the prefrontal cortex during standardized cognitive tasks (nback
      test) will be measured. Additionally, saliva samples will be collected the morning of the
      test day, and before and after the interventions.
    

Intervention name(s): Prolonged sitting (social breaks); Prolonged sitting with step-up exercise break; Prolonged sitting with simple resistance activity breaks
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Participants are required to sit for 80 minutes doing schoolwork, with a toilet break in between. Every twenty minutes participants will have a short social break. Test day begins at 8:00 with pretest measures, followed by the intervention at about 9:00, which will end around 12:00, with subsequent posttest measures.; Participants are required to sit for 80 minutes doing schoolwork, with a toilet break in between. Every twenty minutes participants will have a physical activity break, where they will perform a simple moderate-intensity step-up exercise for three minutes at a predetermined pace. Test day begins at 8:00 with pretest measures, followed by the intervention at about 9:30, which will end around 12:00, with subsequent posttest measures.; Participants are required to sit for 80 minutes doing schoolwork, with a toilet break in between. Every twenty minutes participants will have a physical activity break, where they will perform simple resistance activities following a video for about three minutes. Test day begins at 8:00 with pretest measures, followed by the intervention at about 9:30, which will end around 12:00, with subsequent posttest measures.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention