Acute Effects of Sitting and Physical Activity on Brain Health
Condition: Healthy Adults
Study type: Interventional

Summary: 
      The specific aim of this study is to understand how a working day composed of prolonged
      sitting, sitting regularly interrupted by light aerobic exercise or resistance exercise
      affects an important mechanism underpinning healthy brain functions, namely cerebral blood
      flow. It is primarily focused on investigating these effects in ecologically valid
      conditions, i.e. activity patterns that closely resemble a typical day at the office.
    

Detailed description: 
      The study will be a controlled crossover experimental trial with three conditions involving
      13 adult participants aged between 40 and 60 years. Each participant will complete each of
      the three experimental conditions, separated by a washout period of minimum four days. As
      well, physical activity behaviours and sleep the day/night before the test day will be
      measured. The first visit will be a familiarization session. On the second, third, and fourth
      visits, participants will undergo three different standardized 3-hour interventions in a
      randomized order. Before and immediately after the three-hour interventions, blood pressure,
      augmentation index, and cerebral hemodynamic response of the prefrontal cortex during
      standardized cognitive tasks (1,2, and 3-back tests) will be measured. Additionally, saliva
      samples will be collected the morning of the test day and before and after the interventions,
      blood glucose will be assessed continuously during the trial, and fitness will be measured at
      the familiarization visit.
    

Intervention name(s): Prolonged sitting with social break; Prolonged sitting with walk break; Prolonged sitting with simple resistance activities
Intervention type(s): Behavioral; Behavioral; Behavioral
Intervention description(s): Participants are required to sit for three hours (reading is permitted), with a toilet break in between. Every thirty minutes participants will have a short social break. Test day begins at 7:30 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 three hours (reading is permitted), with a toilet break in between. Every thirty minutes participants will have a physical activity break, where they will perform a brisk walk for about three minutes on a treadmill at a predetermined speed and grade based on the fitness test performed during the familiarization session. Test day begins at 7:30 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 three hours (reading is permitted), with a toilet break in between. Every thirty 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 7:30 with pretest measures, followed by the intervention at about 9:00, which will end around 12:00, with subsequent posttest measures.
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention