Healthy Adolescents
Conditions
Brief 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.
Interventions
BEHAVIORALProlonged sitting (social breaks)
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.
BEHAVIORALProlonged sitting with step-up exercise break
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.
BEHAVIORALProlonged sitting with simple resistance activity breaks
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.
Sponsors
The Knowledge Foundation
IKEA
Skandia
Konsumentföreningen Stockholm
Generation PEP
COOP
The Swedish School of Sport and Health Sciences
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
13 Years to 14 Years
Healthy volunteers
Yes
Exclusion criteria
* Ongoing medication that can affect central circulation or brain circulation * Ongoing infection * Inability to apprehend information about the study or to perform the tests
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in cerebral blood flow | before to after 80 minutes intervention | Oxygenated and deoxygenated hemoglobin concentration changes measured with functional near-infrared spectroscopy |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Augmentation index | before and after 80 minutes intervention | measure of arterial stiffness |
| Cortisol | morning; before and after 80 minutes intervention | measured from saliva |
| Cognitive performance | before and after 80 minutes intervention | nback cognitive test (time and accuracy) |
| Sleepiness | at the beginning of the day; before and after 80 minutes intervention | Karolinska Sleepiness Questionnaire; goes from 1 (extremely alert) to 9 (extremely sleepy) |
| Alertness | at the beginning of the day; before and after 80 minutes intervention | 100mm Visual Analogue Scale (VAS); range: 'not at all' to 'completely alert' |
| Mood | at the beginning of the day; before and after 80 minutes intervention | Positive and Negative Affect Schedule (PANAS) comprised of 20 affect states (10 positive and 10 negative), each affect state scored on a scale going from 1 (very slightly or not at all) to 5 (extremely) |
Countries
Sweden
Outcome results
None listed