Sitting for long periods of time has become increasingly common in modern society. With growing reliance on computers, video games, and televisions for work and leisure, many people find themselves sitting down for hours on end each day. However, research shows that excessive sitting can have serious negative effects on health. This article will explore the question “What happens if you sit too long?” by looking at the potential risks and health consequences.
How much sitting is too much?
There is no definitive threshold for how much sitting is dangerous, but health experts recommend breaking up long bouts of sitting as often as possible. Sitting for more than 30 minutes at a time without getting up has been associated with negative effects. Other research suggests limiting total sitting time to less than 3 hours per day for better health outcomes. The more often you can interrupt sitting throughout the day, the better.
Increased risk of obesity and weight gain
Prolonged sitting is linked to a higher risk of obesity and excessive weight gain over time. When you sit, your body burns fewer calories as compared to when you are up moving around and engaging your muscles. Just standing up engages your leg and core muscles more than sitting. The metabolic rate—the rate at which the body burns calories—slows down with extended inactivity. This means prolonged sitting gives the body less opportunity to burn calories from food intake, making weight control more challenging.
How weight gain happens with prolonged sitting
– Fewer calories burned: Sitting for long periods burns about 80 fewer calories per hour compared to moderate activity like walking. This adds up over the course of a day.
– Reduced metabolism: Excessive sitting slows down the metabolism, the body’s engine for burning calories. The body converts unused calories to fat rather than burning them off.
– Increased appetite: Sitting for long periods has been linked to increased appetite and excess food intake, even when you are not hungry. This makes it more challenging to maintain energy balance.
– Loss of muscle mass: Prolonged inactivity leads to loss of muscle mass over time. Muscle burns more calories than fat, so less muscle means fewer calories burned.
Increased risk of type 2 diabetes and heart disease
Studies consistently show excessive sitting increases the risk of developing type 2 diabetes and cardiovascular disease. Sitting for many hours appears to alter normal biological processes, leading to:
– Reduced insulin sensitivity, which can progress to insulin resistance and type 2 diabetes
– Increased blood sugar levels, cholesterol, and triglycerides
– Higher blood pressure
– Excess visceral fat around the abdomen
These metabolic changes promote inflammation, atherosclerosis (hardening of the arteries), and the development of heart disease over time. Breaking up sitting time and getting regular activity helps regulate blood sugar and prevent metabolic dysfunction.
Musculoskeletal discomfort
Staying seated in one position for a prolonged period can lead to aches and pains throughout the body, especially in the lower back, neck, shoulders and hips. Some key reasons why include:
Poor posture
Slumping forward or slouching for long periods strains the muscles, tendons and discs in the spine. This commonly causes general back, neck and shoulder discomfort.
Weakened muscles
Underused muscles in the legs, back and core become weaker and less supportive of proper posture. This stresses the joints and can lead to pain.
Reduced circulation
Sitting still inhibits blood flow, which allows fluid and waste products to build up in muscles. This leads to stiffness, soreness, swelling and tightness.
Weight impact
The hips and thighs support the full weight of the upper body when seated. Gravity compresses the hips, pelvis and spine, straining the structures.
Regular movement helps lubricate joints, improve circulation to the muscles and reduce the static load on the body imposed by long periods of stillness.
Increased cancer risk
Some research points to a correlation between prolonged sitting time and increased cancer risk, especially for colorectal, endometrial and possibly breast cancers. Exact mechanisms are still being studied but may involve:
– Impaired metabolism and excess insulin production, which can promote tumor growth
– Reduced antioxidant levels and increased inflammation
– Weaker immune function
More research is needed to confirm a direct causal relationship between sitting and cancer. However, reducing sitting time may provide protective effects against cancer development and progression.
Deep vein thrombosis
Prolonged sitting slows blood circulation, especially in the legs, which can promote development of blood clots known as deep vein thrombosis (DVT). When blood pools in the lower extremities, it triggers the abnormal formation of clots. If a clot travels to the lungs it can cause a pulmonary embolism, a dangerous blockage of an artery.
Those at higher risk include:
– Older adults
– Pregnant women
– Individuals with a previous history of DVT
– Those recovering from surgery
– Obese individuals
– Smokers
– Anyone taking contraceptives or hormone therapy
Moving the muscles periodically when sitting for long stretches helps keep blood flowing and lowers DVT risk.
Effects on mental health
Excess sitting may also negatively impact mental well-being. Studies link prolonged sedentary time to:
– Increased risk of depression and anxiety
– Impaired cognitive function
– Poorer work productivity and academic performance
– Behavioral problems in children and adolescents
Getting regular physical activity, even light activity, releases endorphins that boost mood and psychological outlook. Social interaction and exposure to nature, both facilitated by less sitting, also benefit mental health.
Premature death
Strong evidence from multiple studies draws a correlation between excessive sitting time and increased risk of early mortality. The combination of adverse metabolic, cardiovascular, mental health effects contribute to greater mortality risk overall.
Some research suggests sitting more than 10 hours per day increases risk of premature death significantly compared to sitting less than 4 hours per day. The exact amount of sitting that substantially elevates mortality risk is not definitively established. In general, minimizing total sitting time may promote longevity.
Tips to avoid excessive sitting
Here are some simple strategies to avoid the negative effects of prolonged sitting:
Take standing or movement breaks every 30 minutes
Set a reminder to get up and walk around, stretch, or do some light exercise for at least a few minutes every half hour. This interrupting sitting significantly.
Try a standing desk
Working at a standing desk or counter can reduce sitting time, especially for desk jobs. Adjustable desks allow you to alternate between sitting and standing.
Walk during phone calls or meetings
Use opportunities like phone conferences to walk around or pace rather than sit. Even light activity engages muscles and burns more calories.
Replace sitting with activity when possible
Stand or walk when watching TV. Take the stairs instead of the elevator. Park farther away and walk. Do household chores like cleaning to get activity in.
Set hourly activity goals
Aim for 5-10 minutes of some activity every hour. Simple exercises, a walk around the office or home, using stairs, stretching etc.
Try a standing commute
Stand rather than sit when commuting via car, train, bus or subway to reduce sitting time. This engages the core and lower body.
| Sitting Habit | Healthier Alternatives |
|---|---|
| Watching TV for hours | Take movement breaks during shows, stretch, walk in place. Stand while watching. |
| Desk work | Use a standing desk option. Take regular standing breaks. |
| Driving long distances | Stop to walk and stretch legs every 2 hours. Stand while driving if possible. |
| Reading/tablet use | Sit on an exercise ball. Stretch hips and legs between chapters or pages. |
| Commuting/public transit | Stand and hold handrails rather than sit if possible. Walk or bike if feasible. |
| Computer use | Set hourly alerts to get up and move. Try a treadmill desk. |
| Video gaming | Take standing stretch breaks during loading screens or level changes. |
Conclusion
Prolonged sitting should be minimized as much as possible throughout the day for better health. Taking brief activity breaks every 30 minutes can help reduce the risks linked to excessive sitting. Replacing sitting with light movement or standing whenever possible is recommended. Being mindful of total sitting time and aiming for less than 3 hours per day may provide significant benefits. Consistent exercise is also essential for mitigating the negative impacts of unavoidable sitting. Overall, a combination of more movement of any kind and less static sitting may greatly improve health.