The Effect of Frequency and Duration of Breaks in Sitting Time on Metabolic Cardiovascular Risk Factors

Study Overview
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Brief Summary
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The primary aim of this study is to investigate the acute effect of the frequency and duration of breaks in sitting time on the metabolic risk factor profile.

Detailed Description
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Fifteen (n=15) sedentary adult overweight males will be included in the study. All participants will undergo the four interventions in a randomized cross-over design. Wash out between intervention will be minimum four days. Control (CON): Participants will be sedentary. Sedentary time will be spent sitting in a chair, restricted to sedentary behaviors (working on a computer, reading, watching TV, etc.), with a target MET below 1.5 (i.e. 1.5 times REE). Participants will only be allowed to stand or walk to go to the toilet. Breaker: Participants will be breaking up prolonged sitting with 2 min intervals of low intensity walking. Intermediate: Participants will be breaking up prolonged sitting with 6 min intervals of low intensity walking Prolonger: Participants will be breaking up prolonged sitting with 12 min intervals of low intensity walking All interventions will be matched for total physical activity as well as sitting. Thus, we aim for the active interventions to be iso-caloric.

Official Title
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The Effect of Frequency and Duration of Breaks in Sitting Time on Metabolic Cardiovascular Risk Factors

Conditions
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Sedentary Lifestyle, Overweight and Obesity, Metabolic Disease

Intervention / Treatment
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* Behavioral: Control
* Behavioral: Breaker
* Behavioral: Prolonger
* Behavioral: Intermediate


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Males, age 20-50 years, waist-to-height ratio ≥ 0.5 and/or waist circumference ≥ 102 cm. Exclusion Criteria: Clinically diagnosed diabetes, uncontrolled hypertension, use of glucose- and/or lipid-lowering medication, smoking, evidence of thyroid, liver, lung, heart or kidney disease, non-sedentary occupation, and VO2max levels above the considered average fitness according to age (Shvartz & Reibold 1990), contraindications to increased levels of physical activity.

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Male

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Control<br>Participants will spend 8 hours sedentary. Sedentary time will be spent sitting in a chair, restricted to sedentary behaviors (working on a computer, reading, watching TV, etc.) Participants will only be allowed to stand or walk to go to the toilet. | Behavioral: Control<br>* Control intervention<br>|
| Experimental: Breaker<br>Participants will spend a total of 7 hours and 12 min sedentary and a total of 48 min breaking sitting time with LPA. Sedentary time will be done in bouts of 18 min with 2 min of light walking. | Behavioral: Breaker<br>* Short breaks of physical activity<br>|
| Experimental: Intermediate<br>Total duration of sedentary time and LPA time will be the same as in Breaker. Sedentary time will be done in bouts of 54 min with 6 min of LPA between each bout. | Behavioral: Intermediate<br>* Intermediate breaks of physical activity<br>|
| Experimental: Prolonger<br>Total duration of sedentary time and LPA time will be the same as in Breaker. Sedentary time will be done in bouts of 108 min with 12 min of LPA between each bout. | Behavioral: Prolonger<br>* longer breaks of physical activity<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AUC post prandial glucose concentration |  | 6 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| AUC post prandial insulin concentration |  | 6 hours | 
| AUC post prandial c-peptide concentration |  | 6 hours | 
| AUC post prandial triglyceride concentration |  | 6 hours | 
| AUC post prandial total cholesterol concentration |  | 6 hours | 
| AUC post prandial ldl concentration |  | 6 hours | 
| AUC post prandial hdl concentration |  | 6 hours | 
| AUC post prandial glucagon concentration |  | 6 hours | 
| Mean 24 hour glucose concentration |  | 24 hours | 
| Variation in 24 hour glucose concentration |  | 24 hours | 
| Maximum in 24 hour glucose concentration |  | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Exercise, Breaking prolonged sitting, physical activity