Fifty years ago, most people's daily levels of activity were equivalent to walking three to five miles a day; today, the average person fails to cover that distance in a week.

    It's no wonder the incidence of obesity has soared - with serious implications for health.

    The culprit? Inertia. What we have gained in convenience from labour-saving devices over the past half-century, we have paid for in terms of a sharp decline in physical activity.

    We use cars, buses or trains to get to work; our children are driven to school; escalators and lifts have replaced conventional stairs in shopping centres, offices and apartment blocks.

    Washing machines, vacuum cleaners, dishwashers and electric mowers all minimise the effort required to maintain a clean and tidy home.

    Television has us tethered to the sofa.

    Almost one third of adults spend over ten hours sitting down every day, adding up to a staggering average of 32 years and four months over a lifetime.

    Hardly surprising, then, that researchers blame this sedentary lifestyle for our weight gain.

    Of course, our diets have changed, too, but the fact is we consume fewer calories now than in the 1960s.

    Our waistlines are expanding for one major reason: increasing inactivity.

    So what is the solution?

    The secret is integrated exercise. This involves going about your normal daily life - but doing it with more gusto.

    It might mean standing to answer the phone and pacing the room, tapping your feet on the floor as you work.

    It means never taking the car when you could walk; it means standing on short train and bus journeys, or walking at a pace where you feel you might break into a run if you were to go any faster.

    A Dutch study found that people who spend more time doing moderate, integrated-style exercise burned more calories than those who performed shorter, sharper workouts.

    半個(gè)世紀(jì)前，大多數(shù)人每天的活動(dòng)量相當(dāng)于步行三至五英里，而如今，普通人一周的活動(dòng)量還不到這個(gè)水平。

    所以肥胖率的上升不足為奇，而這一問(wèn)題則對(duì)健康造成了嚴(yán)重影響。

    罪魁禍?zhǔn)资钦l(shuí)？懶惰！半個(gè)世紀(jì)以來(lái)，我們從各種節(jié)省人力的設(shè)備中得到很多便利，但這是以我們身體活動(dòng)的大大減少為代價(jià)的。

    我們上班要么開(kāi)車(chē)、要么乘公交或坐城鐵；我們開(kāi)車(chē)送孩子上學(xué)；購(gòu)物中心、辦公大樓和公寓里傳統(tǒng)的樓梯都換成了扶梯和電梯。

    洗衣機(jī)、吸塵器、洗碗機(jī)和除草機(jī)讓我們不費(fèi)力氣就能保持家庭整潔。

    電視機(jī)讓我們陷入沙發(fā)，不能自拔。

    近三分之一的成年人每天坐著的時(shí)間超過(guò)十小時(shí)，照此計(jì)算，他們一生中坐著的時(shí)間竟達(dá)到三十二年零四個(gè)月！

    所以，研究人員將發(fā)胖歸咎于這種久坐的生活習(xí)慣不無(wú)道理。

    當(dāng)然，我們的飲食也發(fā)生了變化，但事實(shí)在于，與上世紀(jì)60年代相比，如今我們消耗的能量減少了。

    身體活動(dòng)的日益減少是我們腰圍見(jiàn)長(zhǎng)的一個(gè)主要原因。

    那么如何解決這個(gè)問(wèn)題呢？

    秘訣就是“綜合性鍛煉”。這得從你的日常生活做起——但一定要充滿(mǎn)熱情地去做。

    比如，你可以站著接電話(huà)、可以在房間里溜達(dá)、辦公時(shí)雙腳可以拍拍地板。

    可以步行時(shí)，絕對(duì)不要“以車(chē)代步”；乘短途火車(chē)和坐公交車(chē)時(shí)最好站著；快步走，以再快一點(diǎn)就會(huì)跑起來(lái)的速度走路。

    荷蘭一項(xiàng)研究發(fā)現(xiàn)，經(jīng)常進(jìn)行適度綜合性鍛煉的人比在短時(shí)間內(nèi)進(jìn)行高強(qiáng)度健身的人消耗的熱量多。