July 12, 2017
View Full PaperEffect of alternating standing and sitting on blood pressure and pulse wave velocity during a simulated workday in adults with overweight/obesity
Key Result
Alternating standing and sitting during a simulated workday significantly decreased diastolic blood pressure (mean difference -1.0 mmHg, P=0.020) and carotid-ankle PWV compared to continuous sitting.
Study Design
Type
RCT (n=25)
Randomization
crossover
Structured PICO
Does alternating standing and sitting reduce blood pressure and pulse wave velocity in overweight/obese adults with pre-to-Stage 1 hypertension?
P
Population
25 overweight/obese adults with pre-to-Stage 1 hypertension completed a randomized crossover study during a simulated workday.
I
Intervention
STAND-SIT condition (alternating standing and sitting every 30 min) using a sit-stand desk during a simulated workday
C
Comparator
SIT condition (continuous sitting) during a simulated workday
O
Outcome
Blood pressure (SBP, DBP, MAP) measured hourly and pulse wave velocity (carotid-femoral, carotid-radial, carotid-ankle) measured morning, mid-day, and late afternoonsurrogate
Interrupting prolonged sitting with intermittent standing slightly but significantly decreases DBP, MAP, and carotid-ankle PWV in overweight/obese adults with elevated blood pressure.
Main Result
Mean Difference: -1
p-value: p=0.020
Limitations
- Clinical significance of the observed effects is modest
Abstract
OBJECTIVE: Reducing prolonged sitting at work has been recommended by an expert panel, but whether intermittent standing improves vascular health is unclear. We aimed to test whether using a sit-stand desk could reduce blood pressure (BP) and pulse wave velocity (PWV) during a simulated workday. METHODS: Overweight/obese adults with pre-to-Stage 1 hypertension completed a randomized crossover study with two simulated workday conditions: STAND-SIT (alternating standing and sitting condition every 30 min) and SIT (continuous sitting condition). Oscillometric BP was measured hourly. Carotid-femoral, carotid-radial, and carotid-ankle PWV were measured in the morning, mid-day, and late afternoon using tonometry. RESULTS: Participants n = 25, 64% male, 84% white, mean (SD) age: 42 (12) years had average resting SBP of 132 (9) mmHg and DBP of 83 (8) mmHg. In linear mixed models, STAND-SIT resulted in a significantly lower DBP (mean ± SE: -1.0 ± 0.4 mmHg, P = 0.020) and mean arterial pressure (MAP) (-1.0 ± 0.4 mmHg, P = 0.029) compared with SIT. SBP (-0.9 ± 0.7 mmHg, P = 0.176) was not different across conditions. Carotid-ankle PWV was significantly lower during the STAND-SIT vs. SIT condition (-0.27 ± 0.13 m/s, P = 0.047), whereas carotid-femoral PWV (-0.03 ± 0.13 m/s, P = 0.831) and carotid-radial PWV (-0.30 ± 0.18 m/s, P = 0.098) were not. Changes in MAP partially explained changes in PWV. CONCLUSION: Interrupting prolonged sitting during deskwork with intermittent standing was a sufficient stimulus to slightly, but statistically significantly, decrease DBP, MAP, and carotid-ankle PWV. Though the clinical significance of the observed effects is modest, regular use of a sit-stand desk may be a practical way to lower BP and PWV while performing deskwork.