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.

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.

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