Sedentary Lifestyle
Conditions
Keywords
worksite, intervention, sitting
Brief summary
The purpose of this study is to determine whether varying the frequency and length of activity breaks during the workday will differentially impact sedentary behavior and health outcomes. Participants will be randomly assigned to take short, frequent breaks (i.e., 1 minute every half hour) or longer, planned breaks (i.e., two 15-minute walks) from sitting during the workday. They will be instructed to follow the assigned protocols for an 8-week intervention and the effects of their participation on sedentary behavior and a variety of health outcomes will be assessed. The investigators anticipate participants in both intervention arms will demonstrate significant reductions in daily sitting time, bit do not have an a priori hypothesis regarding the relative effectiveness of each approach.
Detailed description
The purpose of this study is to determine whether varying the frequency and length of activity breaks during the workday will differentially impact sedentary behavior and health outcomes. Women aged 25-50 who work full-time in sedentary jobs and participate in less than 60 minutes of overall physical activity per week will be recruited. At the beginning of the study participants will visit the laboratory to complete baseline health assessments and meet with a research assistant to outline their plan for reducing sitting time at work. At this time they will be randomly assigned to one of two groups: 1) Group A will be asked to take two 15-minute walks during each workday, or 2) Group B will be asked to stand up and move around for 1-2 minutes every half hour throughout the workday. The total duration of this program will be eight weeks. During this time participants will be asked to keep a brief daily log of their activity breaks during the workday. At the end of the 8-week program participants will return to the laboratory to repeat the health assessments. ASSESSMENTS: All participants will complete the following tests and procedures: * Metabolic blood panel. Blood will be drawn from a quick finger stick to assess total cholesterol, triglycerides, LDL, HDL, and fasting glucose. * DEXA scan. Participants will lie down on a body scanner for about 10 minutes to assess body composition. * Body measurements. A trained research assistant will measure height, weight, and waist circumference. * Blood pressure. A trained research assistant will measure blood pressure using an automated blood pressure cuff. In addition, participants will complete the following assessments outside of the laboratory: * Questionnaires: Participants will be asked to complete a series of questionnaires. This should take 15-20 minutes. * Accelerometer: Participants will be asked to wear a motion sensor for a total of 21 days (three 7-day periods). This small apparatus is worn around the waist during the day. Participants will complete a log indicating when they were wearing the accelerometer each day. * Food diary: Participants will be asked to record their food intake for a total of 9 days (three 3-day periods).
Interventions
Following baseline testing, participants will attend a 30-minute individual orientation session, during which they will complete a planning worksheet with a research assistant. They will identify specific strategies they will use to accomplish the pre-specified goal (i.e., to take a 1-minute active break every 30 minutes during the workday). They will also identify potential barriers they will face and devise strategies for overcoming them. The intervention will officially start the Monday after the orientation session and will last for 8 weeks. Participants will receive a weekly email containing tips related to reducing sitting time at work. All participants will complete daily activity logs indicating the time and duration of all breaks from sitting across the 8-week intervention.
Following baseline testing, participants will attend a 30-minute individual orientation session, during which they will complete a planning worksheet with a research assistant. They will identify specific strategies they will use to accomplish the pre-specified goal (i.e., to take two 15-minute activity breaks during each workday). They will also identify potential barriers they will face and devise strategies for overcoming them. The intervention will officially start the Monday after the orientation session and will last for 8 weeks. Participants will receive a weekly email containing tips related to reducing sitting time at work. All participants will complete daily activity logs indicating the time and duration of all breaks from sitting across the 8-week intervention.
Sponsors
Study design
Eligibility
Inclusion criteria
1. Work at least 35 hours per week 2. Spend at least 80% of working hours sitting (self-reported) 3. Engage in less than 60 minutes per week of leisure-time exercise (self-reported) 4. Not pregnant or planning to become pregnant in the next 3 months 5. Not currently trying to change weight 6. Speak English 7. Able to attend assessments 8. Willing to wear accelerometer 9. No anticipated significant conflicts during 8-week intervention
Exclusion criteria
1. Male 2. Working less than 35 hours per week 3. Spend \>25% of working hours standing or active 4. Engage in more than 60 minutes per week of leisure-time exercise 5. Pregnant 6. Actively dieting or attempting to change weight
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in sedentary behavior during the workday | Baseline - week 8 | Measured by GT3X accelerometer |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in resting heart rate | Baseline - week 9 | — |
| Change in total cholesterol, HDL cholesterol, LDL cholesterol | Baseline - week 9 | — |
| Change in triglycerides | Baseline - week 9 | — |
| Change in fasting blood glucose | Baseline - week 9 | — |
| Change in weight | Baseline - week 9 | — |
| Change in waist circumference | Baseline - week 9 | — |
| Change in body composition | Baseline - week 9 | DEXA or bioelectrical impedance |
| Change in blood pressure | Baseline - week 9 | — |
| Change in fatigue severity, interference, and duration | Baseline - week 8 | Fatigue Symptom Inventory |
| Change in mood | Baseline - week 8 | Positive and Negative Affect Scale |
| Change in overall self-reported physical activity | Baseline - week 8 | International Physical Activity Questionnaire |
| Change in overall objectively measured physical activity | Baseline - week 8 | Measured by GT3X accelerometer |
| Change in diet quantity | Baseline - week 8 | Measured by 3-day food diary |
| Change in diet quality | Baseline - week 8 | Dietary Screener Questionnaire |
| Adherence to assigned protocols | up to 8 weeks | Measured by activity logs |
| Change in energy, tiredness, tension, and calmness | Baseline - week 8 | Activation-Deactivation Checklist |