Right now, you're probably sitting down to watch this video and staying seated for a few minutes to view it is probably okay. But the longer you stay put, the more agitated your body becomes. It sits there counting down the moments until you stand up again and take it for a walk. That may sound ridiculous. Our bodies love to sit, right? Not really. Sure, sitting for brief periods can help us recover from stress or recuperate from exercise. But nowadays, our lifestyles make us sit much more than we move around, and our bodies simply aren't built for such a sedentary existence. In fact, just the opposite is true. The human body is built to move, and you can see evidence of that in the way it's structured. Inside us are over 360 joints, and about 700 skeletal muscles that enable easy, fluid motion. The body's unique physical structure gives us the ability to stand up straight against the pull of gravity. Our blood depends on us moving around to be able to circulate properly. Our nerve cells benefit from movement, and our skin is elastic, meaning it molds to our motions. So if every inch of the body is ready and waiting for you to move, what happens when you just don't? Let's start with the backbone of the problem, literally. Your spine is a long structure made of bones and the cartilage discs that sit between them. Joints, muscles and ligaments that are attached to the bones hold it all together. A common way of sitting is with a curved back and slumped shoulders, a position that puts uneven pressure on your spine. Over time, this causes wear and tear in your spinal discs, overworks certain ligaments and joints, and puts strain on muscles that stretch to accommodate your back's curved position. This hunched shape also shrinks your chest cavity while you sit, meaning your lungs have less space to expand into when you breath. That's a problem because it temporarily limits the amount of oxygen that fills your lungs and filters into your blood. Around the skeleton are the muscles, nerves, arteries and veins that form the body's soft tissue layers. The very act of sitting squashes, pressurizes and compresses, and these more delicate tissues really feel the brunt. Have you ever experienced numbness and swelling in your limbs when you sit? In areas that are the most compressed, your nerves, arteries and veins can become blocked, which limits nerve signaling, causing the numbness, and reduces blood flow in your limbs, causing them to swell. Sitting for long periods also temporarily deactivates lipoprotein lipase, a special enzyme in the walls of blood capillaries that breaks down fats in the blood, so when you sit, you're not burning fat nearly as well as when you move around. What effect does all of this stasis have on the brain? Most of the time, you probably sit down to use your brain, but ironically, lengthy periods of sitting actually run counter to this goal. Being stationary reduces blood flow and the amount of oxygen entering your blood stream through your lungs. Your brain requires both of those things to remain alert, so your concentration levels will most likely dip as your brain activity slows. Unfortunately, the ill effects of being seated don't only exist in the short term. Recent studies have found that sitting for long periods is linked with some types of cancers and heart disease and can contribute to diabetes, kidney and liver problems. In fact, researchers have worked out that, worldwide, inactivity causes about 9% of premature deaths a year. That's over 5 million people. So what seems like such a harmless habit actually has the power to change our health. But luckily, the solutions to this mounting threat are simple and intuitive. When you have no choice but to sit, try switching the slouch for a straighter spine, and when you don't have to be bound to your seat, aim to move around much more, perhaps by setting a reminder to yourself to get up every half hour. But mostly, just appreciate that bodies are built for motion, not for stillness. In fact, since the video's almost over, why not stand up and stretch right now? Treat your body to a walk. It'll thank you later.
現在你大概正坐著要看這影片吧 坐住幾分鐘來觀看它也許沒啥問題 但是你一動也不動得越久 你的身體就會變得越焦慮 它坐在那裡倒數著時間直到你再次起身 帶著它去散個步 這聽起來也許很荒謬 我們的身體就喜歡坐著不是嗎? 事實則不然 坐一下子的確可以消除緊張 或是運動後恢復體力 只不過當今的生活型態使得我們 坐著的時候遠遠多過於在動的時候 而我們的身體明明就不是 為了如此缺乏運動的生活而打造的 事實上恰恰相反才對 身體是為了移動而打造的 我們可從其架構之方式找到證據 我們體內有超過 360 個關節 以及大約 700 條能讓輕鬆、 流利之動作體現的骨骼肌 人體獨特的身體結構給了我們 抗拒重力的拉力而站直的能力 血液有賴於我們四處動 才有辦法完善地循環 我們的神經細胞能從運動中受益 皮膚是有彈性的 代表它可以貼合我們的動作 假若全身上下都準備好了 就等著你去動 而你就是不動那會怎麼樣呢? 讓我們從這問題的「中樞」開始來講: 你的脊椎是由骨頭組成 而椎間盤坐落於其間的長條結構 附著於脊椎骨的關節、肌肉和韌帶 把它包覆在一起的 一般的坐法帶著微曲的背部、下放的雙肩 是一種讓脊椎受力不均的姿勢 長時間下來會造成椎間盤磨損、 過度操用部分韌帶與關節 以及對延展以配合你微曲 背姿的肌肉造成壓迫 當你彎腰坐著還會限縮到你的胸腔 表示當你呼吸時肺部只有 較小的空間能吸進擴張 這就是個問題了 因為它會暫時地限制住充填你的肺部 和濾進血液裡的氧氣量 骨骼週圍是組成人體軟組織層的 肌肉、神經與血管 「坐下」這動作就是在壓平、壓迫、擠壓 而且這些較為嬌嫩的細胞 確實感受得到壓力 你是否有過坐著時下肢麻木、腫脹? 承受最大壓力的部位中 神經、血管會被阻斷 阻礙神經訊號會導致下肢麻木 還有使流進下肢的血液變少 造成下肢水腫 長時間坐著還會暫時地讓 「脂蛋白脂肪酶」失去功用 那是一種特殊酶素 在血管壁裡摧毀血液當中的脂肪 所以在坐著時燃燒脂肪很難做到 接近與你在動的時候一樣好 到底這種靜滯對大腦有什麼影響呢? 絕大多數時間你大概是坐著動腦 不過諷刺的是久坐 事實上與這個目標背道而馳 在靜止不動之下會讓血液流量 以及經肺部進入血液的氧含量變少 你的大腦要保持清醒兩者都需要 因此當你的大腦運作慢下來了 你的專注程度極可能下滑 很不幸地一直坐著的負面影響 不是只限於短期而已 最近研究發現久坐與某些類型的 癌症、心臟疾病有關 還會導致糖尿病與肝、腎之毛病 事實上研究人員們已經計算出在全世界 欠缺運動造成一年大約 9 % 的早逝率 那可是5百多萬人呀 所以這種看似無害之習慣者 其實對健康影響深遠 不過幸好對這種積累性危害的 解決之道既簡單又不需動腦 當你非坐不可時 試著把無精打采的彎著腰 轉換成挺直的胸膛 而當你不必黏在位置上時 訂下運動更多的目標吧 也許利用設定每半小時 站起來一次的提醒給自己 最主要的是要理解你的身體 是為了動作而非呆滯而生 這影片即將結束 何不站起來伸展一下呢 犒賞身體去散個步 稍後它將會感謝你的!