Breaking of Sitting Time Prevents Lower Leg Swelling

Study Overview
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Brief Summary
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Sitting or standing during a prolonged and uninterrupted period of time is related to negative health outcomes, such as lower extremity swelling. It is unknown if interrupting sedentary behavior by including brief bouts of standing up to the sitting time can attenuate lower leg swelling. Thus, our purpose is to examine if breaking sitting time by adding sit-to-stand transitions attenuates or even prevents lower leg swelling, compared with uninterrupted motionless standing and uninterrupted motionless sitting, using localized bioelectrical impedance raw parameters.

Detailed Description
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Increased sedentary behavior has deleterious effects on cognitive function, mental health, physical function, disability as well as quality-of-life. Nowadays, prolonged sitting time has been introduced into many situations such as transportation and in the workplace. Staying in the same position (e.g., sitting/standing) for a long and uninterrupted period is associated with poorer health-outcomes, increasing the risk for premature mortality. For instance, sitting for a long period of time has been associated with lower limbs edema. This condition causes discomfort and pain, in turn associated with a lower quality-of-life. The literature shows that interruption of prolonged sitting time has a positive impact in several health-related risk factors. However, no studies analyzed the effects of motionless sitting with brief standing bouts on lower leg swelling. Thus, the aim of this study is to examine and to compare the effects of standing, sitting and sit-to-stand transitions on lower leg swelling using localized bioelectrical impedance analysis (BIA) measurements A crossover randomized experiment was performed among 20 healthy individuals [age: 27.5±5.9y, 47% females]. In this study, the participants performed the 3 conditions (randomly ordered): 1) uninterrupted motionless standing; 2) uninterrupted motionless sitting; 3) sit-to-stand transitions (1 minute sitting followed by 1 minute standing). Before each condition, a 10-min resting period was performed. Total fat and fat-free mass were determined by dual-energy x-ray absorptiometry. Localized resistance (R), reactance (Xc), impedance (Z) and phase angle (PhA) were assessed at the baseline, at 10 min and at 20 min for each condition. The researchers hypothesized that interrupting a prolonged sitting position with sit-to-stand transitions will result in greater muscle pump, preventing lower leg swelling.

Official Title
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Breaking of Sitting Time Prevents Lower Leg Swelling - Comparison Among Sit, Stand and Intermittent (Sit-to-stand Transitions) Conditions

Conditions
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Edema Leg

Intervention / Treatment
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* Behavioral: Uninterrupted motionless standing
* Behavioral: Uninterrupted motionless sitting
* Behavioral: Sit-to-stand transitions


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI ranging between 18.5 to 29.9 kg/m2; Not taking any medications at the time of the measurements; All women should have a (self-reported) regular menstrual cycle. Exclusion Criteria: Self-reported inability to stand for 20min without moving the lower limbs An active smoking status Presence of diabetes

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
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All

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: Uninterrupted motionless standing<br>20minutes of uninterrupted motionless standing | Behavioral: Uninterrupted motionless standing<br>* Participants remained 20 minutes of uninterrupted motionless standing<br>|
| Experimental: Uninterrupted motionless sitting<br>20 minutes of uninterrupted motionless sitting | Behavioral: Uninterrupted motionless sitting<br>* Participants remained 20 minutes of uninterrupted motionless sitting<br>|
| Experimental: Sit-to-stand transitions<br>20 minutes of sit-to-stand transitions (1 minute sitting with 1 minute standing) | Behavioral: Sit-to-stand transitions<br>* 20 minutes of sit-to-stand transitions (1 minute sitting with 1 minute standing)<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Phase Angle (º) | The bioimpedance AKERN BIA 101/BIVA PRO was used to assess physical parameters. Akern is a phase-sensitive device that measures phase angle (PhA). | 8 weeks | 
| Impedance (Ohm) | The bioimpedance AKERN BIA 101/BIVA PRO was used to assess physical parameters. Akern is a phase-sensitive device that measures impedance (Z). | 8 weeks | 
| Resistance (Ohm) | The bioimpedance AKERN BIA 101/BIVA PRO was used to assess physical parameters. Akern is a phase-sensitive device that measures phase angle (PhA) and impedance (Z), and then calculates resistance (R). | 8 weeks | 
| Reactance (Ohm) | The bioimpedance AKERN BIA 101/BIVA PRO was used to assess physical parameters. Akern is a phase-sensitive device that measures phase angle (PhA) and impedance (Z), and then calculates reactance (Xc). | 8 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Fat Free Mass (kg) | Dual-energy X-ray absorptiometry (DXA; Hologic Explorer-W, Waltham, USA) was used to determine fat-free mass (FFM). A whole-body scan was performed, and the attenuation of X-rays pulsed between 70 and 140kV synchronously with the line frequency for each pixel of the scanned image was measured | 8 weeks | 
| Fat mass (kg) | Dual-energy X-ray absorptiometry (DXA; Hologic Explorer-W, Waltham, USA) was used to determine total fat mass (FM). A whole-body scan was performed, and the attenuation of X-rays pulsed between 70 and 140kV synchronously with the line frequency for each pixel of the scanned image was measured. | 8 weeks | 
| Weight (kg) | Weight was measured in bathing suit and no shoes to the nearest 0.01kg using a weight scale. | 8 weeks | 
| Height (cm) | Height was measured in bathing suit and no shoes to the nearest 0.1cm using a a stadiometer (Seca, Hamburg, Germany), respectively. | 8 weeks | 
| Blood pressure (mmHg) | Blood pressure was measured (seated and bipedal) right before the start of each protocol. During the experimental condition, blood pressure was measured every 5 minutes. | 8 weeks | 
| Heart Rate (bpm) | Heart rate was measured (seated and bipedal) right before the start of each protocol. During the experimental condition, heart rate was measured every 5 minutes. | 8 weeks | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Bioimpedance, Raw BIA parameters, Extracellular water expansion, Sedentary behaviour