久坐後身體會發生什麼變化?

Is it unhealthy to sit for hours?

Sitting for long periods of time with little physical activity is part of what doctors call a sedentary lifestyle. The Centers for Disease Control and Prevention (CDC)Trusted Source states that a sedentary lifestyle without physical activity increases a person's risk for health problems, such as:

  • type 2 diabetes
  • heart disease
  • certain types of cancer, including colon, breast, and uterine cancer

Sitting all day without adequate physical activity can also affect a person's sleep quality, mental health, physical and cognitive abilities, and bone health.

There is no hard and fast answer to the question of how long it is unhealthy to sit. It's different for everyone and may depend on factors such as how much exercise a person gets each day.

A person's risk for health problems from sitting for long periods of time:

  • Low risk: less than 4 hours of sitting time per day.
  • Moderate risk: Sitting 4-8 hours per day.
  • High risk: Sitting 8-11 hours a day.
  • Extremely high risk: Sitting for more than 11 hours a day.

The CDC considers 150 minutes of moderate activity per week sufficient to reduce the risk of certain health conditions associated with a sedentary lifestyle.

What happens to the body after sitting for a long time?

Sitting for long periods of time can have a variety of effects on the body. This can include:

uncomfortable

One study suggests a link between prolonged sitting and musculoskeletal discomfort. Areas where people may experience discomfort include:

  • neck
  • Shoulder
  • Lower limbs
  • lower back
  • buttocks
  • thigh
  • wrist and hand

This study examined the effects of sitting for 2 hours. Studies have found that as time goes by, the level of discomfort in various parts of the body increases.

metabolism slows down

Metabolism is the process by which the body breaks down and uses energy. A research articleTrusted Source shows that sitting for long periods of time can affect your metabolism after eating. The researchers in this article recommend taking regular breaks when sitting for long periods of time to improve metabolism.

blood flow changes

According to the same research article, sitting for long periods of time reduces blood flow, especially in the legs. This can lead to leg swelling, among other consequences.

hypertension

A cross-sectional study links prolonged sitting to high blood pressure, or high blood pressure. 6.3% of office workers in the study had blood pressure higher than 140/90 mmHg. The American Heart Association classifies it as stage 2 hypertension.

Musculoskeletal disorders

One article highlights the association between prolonged sitting and certain lower extremity musculoskeletal disorders.

One article points to a link between prolonged sitting and the following musculoskeletal disorders:

  • neck
  • knee
  • thigh
  • lower back
  • Psychological effects

One study shows that sitting for long periods of time can negatively impact perceived mental state and creative problem-solving abilities.

How to Treat the Effects of Sitting All Day

Being active is the best way to treat or prevent the consequences of sitting all day.

It is recommended that people engage in at least 150 minutes of moderate-intensity activity each week. This may be 5 30 minute sessions over 1 week.

Moderate-intensity activities may include:

  • Go quickly
  • water aerobics
  • Cycling on flat ground

People can start with less strenuous exercise and build endurance over time.

A research articleTrusted Source shows that regular activity provides better benefits than replacing long periods of sitting with long periods of standing.

When to talk to your doctor

Anyone experiencing symptoms of a health condition related to sitting for long periods of time should see a doctor.

Anyone with a pre-existing health condition (such as type 2 diabetes, heart disease, or osteoporosis) may want to talk to a doctor before starting a new exercise regimen.

Healthcare professionals are often able to provide personalized advice on how to perform activities or increase activity levels.

How to prevent the consequences of sitting all day

Staying active is the best way to avoid the consequences of sitting all day. This may include at least 150 minutes of physical activity per week or introducing regular activity breaks.

A systematic review suggests the benefits of breaking up long periods of sitting by moving around regularly.

Tips to avoid sitting all day

People who work in offices can try to avoid sitting all day by:

  • Request a sit-stand desk or workstation
  • Alternate standing and sitting every 30 minutes
  • Hold a walking meeting
  • Stretch frequently while sitting or standing
  • Walk and talk to colleagues instead of sending emails

Is sitting for 8 hours harmful to the body?

Just Stand charity requires sitting for 4 to 8 hours a day as the risk of associated health complications is moderate. It considers sitting for 8 to 11 hours a day to be high risk.

Will you die if you sit for too long?

Sitting all day is part of what doctors call a sedentary lifestyle. According to the World Health Organization (WHO)Trusted Source, physical inactivity is the fourth leading risk factor for death, causing 3.2 million deaths worldwide each year.

One article shows that people who sit and work for long periods of time are nearly 1.4 times more likely to die prematurely after 12 years than people who don't sit and work for long periods of time.

generalize

Sitting all day long without engaging in any physical activity may increase a person's risk for a range of health problems, including heart disease, type 2 diabetes and certain types of cancer. It can also affect sleep patterns and mental health.

However, there are steps people can take to reduce health risks. These include being more physically active overall and breaking up long periods of sitting by moving around.

Review

All comments are moderated before being published

HealthyPIG Magazine

View all
如何判斷雞翅是否變壞?

如何判斷雞翅是否變壞?

重點摘要 雞翅會變質嗎? 如何判斷雞翅是否變壞? 過期雞翅還能食嗎? 雞翅可存放多久? 如何儲存雞翅? 雞翅可以冷凍嗎? 結論 雞翅會變質嗎? 會。皮脂較多、表面不潔或溫度過高時,細菌繁殖更快。 如何判斷雞翅是否變壞? 外觀:皮色發黃、出黑斑或血水。 觸感:表面黏滑、軟爛。 氣...
如何判斷雞蛋是否變壞?

如何判斷雞蛋是否變壞?

重點摘要 雞蛋會變質嗎? 如何判斷雞蛋是否變壞? 過期雞蛋還能食嗎? 雞蛋可存放多久? 如何儲存雞蛋? 雞蛋可以冷凍嗎? 結論 雞蛋會變質嗎? 會。殼面有微孔,溫差及濕度變化會令細菌入侵。 如何判斷雞蛋是否變壞? 水測:沉底=較新鮮;浮起=多半變壞。 打開觀察:蛋白渾濁水樣、蛋黃...
如何判斷羊肉是否變壞?

如何判斷羊肉是否變壞?

重點摘要 羊肉會變質嗎? 如何判斷羊肉是否變壞? 過期羊肉還能食嗎? 羊肉可存放多久? 如何儲存羊肉? 羊肉可以冷凍嗎? 結論 羊肉會變質嗎? 會。脂肪多而易氧化,處理或存放唔好就會變壞。 如何判斷羊肉是否變壞? 顏色:紅轉黑,或出現綠斑。 脂肪:由白轉黃兼有酸味。 氣味:由輕...
如何判斷豬肉是否變壞?

如何判斷豬肉是否變壞?

重點摘要 豬肉會變質嗎? 如何判斷豬肉是否變壞? 過期豬肉還能食嗎? 豬肉可存放多久? 如何儲存豬肉? 豬肉可以冷凍嗎? 結論 豬肉會變質嗎? 會。豬肉表面水活度高,加上處理不潔或溫度過高,容易腐敗。 如何判斷豬肉是否變壞? 顏色:粉紅轉灰、發綠或出斑。 氣味:酸臭、腥臭味濃 ...
如何判斷牛肉是否變壞?

如何判斷牛肉是否變壞?

重點摘要 牛肉會變質嗎? 如何判斷牛肉是否變壞? 過期牛肉還能食嗎? 牛肉可存放多久? 如何儲存牛肉? 牛肉可以冷凍嗎? 結論 牛肉會變質嗎? 會。牛肉含高蛋白同水分,若溫度控制或衛生不當,細菌會快速繁殖,導致變壞。 如何判斷牛肉是否變壞? 顏色:鮮紅轉深褐甚至發黑;脂肪變黃。 ...
成年後懷疑自己有注意力不足過動症(ADHD),應該接受診斷嗎?

成年後懷疑自己有注意力不足過動症(ADHD),應該接受診斷嗎?

在過去,注意力不足過動症(Attention-Deficit/Hyperactivity Disorder, ADHD)多被視為「小孩的病」,很多成年人小時候從未被評估或診斷。直到近年社會對心理健康重視度提升,許多成人才開始懷疑,自己長期以來的專注困難、健忘、衝動或時間管理不良,可能與 ADHD 有關。這種「晚發現」的情況相當普遍,也引發了問題:成年後是否值得接受 ADHD 診斷?

哪些職業對健康影響最大?科學與現實的分析

哪些職業對健康影響最大?科學與現實的分析

在現代社會中,工作佔據了人們生命中相當大的一部分。然而,不同職業對健康的風險並不相同。一些工作性質或環境,會顯著增加慢性病、心理壓力、甚至縮短壽命的風險。以下從科學研究與醫學角度,探討幾類對健康損害較大的職業,並附上相關統計數據。

電擊槍的機制與對人體健康影響

電擊槍的機制與對人體健康影響

在現代執法中,警察常使用所謂「非致命性武器」(less-lethal weapons),其中最廣為人知的便是 電擊槍(Taser)。電擊槍的設計初衷是提供一種介於徒手制服與槍械之間的選擇,藉由暫時性電擊使嫌疑人失去行動能力,以降低致命暴力發生的風險。然而,電擊槍並非完全無害,背後涉及的電流機制與人體生理反應值得深入探討。

PD-(L)1/VEGF「三抗」:腫瘤免疫治療新方向

PD-(L)1/VEGF「三抗」:腫瘤免疫治療新方向

腫瘤治療的新挑戰 近十年來,免疫檢查點抑制劑(Immune Checkpoint Inhibitors, ICIs)改變咗癌症治療格局。當中 PD-1/PD-L1 抑制劑 已經成為多種腫瘤的一線或二線療法,而 VEGF 抑制劑 亦係抗血管生成治療嘅核心藥物。然而,臨床數據顯示,雖然 PD-(L...