Reducing Sitting Time: A Path to Lower Blood Pressure and Better Health
In a groundbreaking study, researchers explored the effects of a behavioral intervention on sitting time and its impact on blood pressure. Here’s what they found and why it matters.
What Was Studied?
The primary focus of the study was to determine whether reducing daily sitting time through a behavioral intervention could lower blood pressure in adults.
Who Was Studied?
The study involved 283 adults with an average age of 69, comprising 66.1% women and 33.9% men. The participants had an average BMI of 35, indicating obesity.
How Was It Studied?
This six-month randomized controlled study divided participants into two groups: a standing intervention group and a control group. The intervention group received 10 health coaching sessions, a study workbook, a wrist-worn fitness monitor, a tabletop standing desk, and a physical activity feedback report at baseline and three months. They set individualized goals to reduce their sitting time by standing more and taking frequent breaks from sitting, utilizing inner reminders (e.g., noticing muscle stiffness), external reminders (e.g., prompts from their fitness monitor), and habit reminders (e.g., standing during daily activities like reading).
The control group also received 10 health coaching sessions and a workbook, but these focused on general healthy living topics, such as healthy eating and sleep, rather than specifically reducing sitting time.
All participants wore a fitness tracker on their wrist for seven days to measure total daily sitting time.
What Were the Results?
Participants in the intervention group reduced their daily sitting time by 32 minutes compared to the control group. Systolic blood pressure decreased by 3.5 mmHg in the standing group, while diastolic blood pressure remained unchanged. Additionally, the intervention group increased their standing time by 28 minutes per day and reduced prolonged sitting bouts (more than 30 minutes at a time) by 0.6 bouts per day compared to the control group.
Secondary outcomes, including body weight, BMI, and waist circumference, did not change in either group.
The Big Picture
Sometimes, health improvements come from simple changes. This study showed that reducing sitting time by just over 30 minutes per day led to a clinically significant reduction in blood pressure. To contextualize this, the nearly 4 mmHg reduction in systolic blood pressure observed in the intervention group is comparable to the benefits seen with other lifestyle interventions.
Reducing sitting time appears to be as effective as other non-pharmacological interventions for lowering blood pressure. Given that standing more and sitting less is a zero-cost intervention requiring no special dietary or physical activity changes, it could easily be adopted by many.
The study aimed to reduce participants’ sitting time by two hours each day, but they achieved only a quarter of this goal. The COVID-19 lockdowns likely contributed to this limitation, as sedentary time increased by nearly two hours per day globally during the pandemic.
Interestingly, the reduction in sitting time did not correlate with an increase in daily step count, suggesting that the blood pressure benefits were not due to increased physical activity. Instead, participants reduced the average length of each sitting bout and the number of prolonged sitting bouts per day.
Health Implications of Prolonged Sitting
Prolonged sitting has unique negative effects on health. Sitting causes major blood vessels in the legs to bend, leading to turbulent blood flow and blood pooling in the lower limbs. Other effects of prolonged sitting include insulin resistance, endothelial dysfunction, changes in fat and carbohydrate metabolism, reduced cardiorespiratory fitness, decreased muscle mass and strength, weight and fat gain, inflammation, and altered blood lipids. Sitting for 30 minutes to a few hours can elevate blood pressure by up to 3 mmHg due to these altered blood flow patterns.
Standing, with legs straightened, likely prevents blood pooling, turbulent blood flow, and the consequent rise in blood pressure. Even more effective than standing are interruptions to prolonged sitting with light, moderate, or vigorous physical activity every 30 to 60 minutes.
The benefits of reducing sitting time extend beyond blood pressure reduction. Interrupting sitting with standing or walking breaks also improves post-meal blood glucose and insulin levels, with walking being more effective. Long-term interventions to reduce sedentary behavior have shown improvements in body weight, waist circumference, body fat, fasting blood glucose and insulin, HbA1c, and HDL-C.
Practical Recommendations
Most people sit too much during the day, making sitting a “natural” part of work and home life. Rather than quitting desk jobs, it’s beneficial to be conscious of sitting time and incorporate frequent activity breaks into daily routines to refresh both body and mind. This is particularly important for those concerned about their blood pressure and overall health.
By making small, manageable changes to reduce sitting time and increase standing and activity breaks, individuals can significantly improve their health and well-being
Call Sikorsky Chiropractic Clinic if Pain is preventing you from standing or walking. Chiropractic Care is safe and effective choice to help restore the body natural function.