Differences in Sitting Versus Standing on Metabolic and Cardiovascular Measurements

Study Overview
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Brief Summary
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This investigations examined the effect that posture has on metabolic and cardiovascular measurements. Further, it will explore the potential for body weight status or physical activity to influence these relationships. All subjects will complete a seated condition and a standing condition in a counterbalanced manner.

Detailed Description
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The purpose of the present study was to evaluate both metabolic and cardiovascular responses to acute bouts of computer work while sitting and standing. Cardiovascular measurements were made using continuous non-invasive blood pressure monitoring and metabolic measurements were made using indirect calorimetry. Subjects will be grouped and analyzed based upon the weight status of the subject. All subjects will complete a seated condition and a standing condition in a counterbalanced manner. Investigators hypothesize that metabolic and cardiovascular responses will be elevated in the standing condition compared to sitting.

Official Title
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Differences in Sitting Versus Standing on Metabolic and Cardiovascular Measurements

Conditions
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Overweight and Obesity

Intervention / Treatment
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* Behavioral: sit/stand


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: healthy adult Exclusion Criteria: Have a history of cancer, cardiac issues, hypertension, pulmonary disease, stroke, neurological or muscular dystrophy, uncontrolled diabetes, or any life threatening chronic conditions. Are currently being treated for infectious mononucleosis, hepatitis, pneumonia, or other infectious diseases. Are unable or unwilling to stand in one position continuously for 15-20 minutes at a time. Use nicotine products, or non-contraceptive hormonal therapy (birth control is okay). Are pregnant or trying to become pregnant. Are not between 18 and 50 years of age.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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All

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Normal Weight<br>Group is determined based upon subjects weight status. Subjects will preform computer work in the seated and standing position in a counterbalanced manner while metabolic and cardiovascular measurements are made. | Behavioral: sit/stand<br>* Subjects will be asked to both sit and stand during a single trial.<br>|
| Overweight/Obese<br>Group is determined based upon subjects weight status. Subjects will preform computer work in the seated and standing position in a counterbalanced manner while metabolic and cardiovascular measurements are made. | Behavioral: sit/stand<br>* Subjects will be asked to both sit and stand during a single trial.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Heart Rate | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be used to measure heart rate based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Systolic Blood Pressure (SBP) | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be used to measure SBP based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Diastolic Blood Pressure (DBP) | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be used to measure DBP based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Oxygen Consumption | Oxygen consumption will be measured using indirect calorimetry. | Approximately 15 minutes in each condition (sitting and standing) | 
| Carbon Dioxide Production | Carbon Dioxide will be measured using indirect calorimetry. | Approximately 15 minutes in each condition (sitting and standing) | 
| Ventilation | Ventilation will be measured using indirect calorimetry. | Approximately 15 minutes in each condition (sitting and standing) | 
| Respiratory Exchange Ration (RER) | RER will be calculated using oxygen and carbon dioxide value measure from indirect calorimetry. | Approximately 15 minutes in each condition (sitting and standing) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Height | Standard stadiometer will be used to measure height in meters. | 1 minute | 
| Weight | Standard scale will be used to measure weight in kilograms. | 1 minute | 
| Body Mass Index (BMI) | Height in meters and weight in kilograms will be used to calculate BMI using the formula BMI = kg/m^2. | 1 minute | 
| Body Composition | Body composition will be measured using air displacement plethysmography. | Approximately 15 minutes | 
| Total Peripheral Resistance (TPR) | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be uses to estimate TPR based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Stroke Volume | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be used to estimate TPR based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Cardiac Output (Q) | Using human non-invasive blood pressure continuous monitoring placed on the middle finger of the non-dominant hand will be used to estimate Q based upon beat-by-beat finger pressure. | Approximately 15 minutes in each condition (sitting and standing) | 
| Muscle Oxygen Saturation | Using Near-inferred spectroscopy muscle oxygen consumption will be monitored. | Approximately 15 minutes in each condition (sitting and standing) |