だいぶ前の話になりますが，気になる語がありますので，アップいたします。NHKの情報番組「あさイチ」（2016年2月8日放送分）を見ておりましたら，たまたま「アクティブ・カウチポテト」という言葉を耳にしました。「カウチポテト」は以前のブログの記事で説明されており，「｟おもに米｠[通例軽べつして]カウチポテト（ソファーにごろんと寝そべって（スナックを食べ）テレビやビデオばかりを見ている人）」（『スーパーアンカー英和辞典』第5版，学研教育出版）（“someone who spends a lot of time sitting and watching television”—LDOCE5）とあります。“active couch potato”とは，「運動する習慣がある人で，特に座っている時間が運動している時間よりも長い人」のことを言います。要は，「運動習慣があるカウチポテト」ということです。座っている時間が長いと，心筋梗塞，糖尿病，肥満などの生活習慣病のリスクが高まることが指摘されているようです。それを予防するには，30分座ったら2-3分立って動く，または，それと同じような効果のある運動をすることがいいと「あさイチ」（2016年2月8日放送分）は伝えていました。
There's no question that regular exercise is essential to health. For the vast majority of our evolutionary history, we've had to exert ourselves -- often quite strenuously -- to get food, find shelter and simply survive. We naturally spent a lot of time outdoors in the sun, walking, hunting, gathering, and performing various other physically-oriented tasks. We had no concept of this as "exercise" or "working out." It was just life.
Things are different today. Most people in modern societies spend the majority of their time indoors, sitting on their butts (like you're probably doing right now). The typical U.S. adult is sedentary for 60 percent of their waking hours and sits for an average of six hours per day (and often much more, in the case of those who work primarily on computers). In fact, being sedentary is now the norm and exercise is primarily seen as an intervention -- something we do to guard against the negative impacts of a sedentary lifestyle.
An Epidemic of Sedentary Behavior: The Perils of Too Much Sitting
This increase in sedentary time and decrease in physical activity has profoundly impacted our health. Too much sitting is associated with numerous problems, ranging from weight gain, to osteoporosis, to cardiovascular disease. For example, research has shown that:
• Sitting decreases the activity of an enzyme called lipoprotein lipase (LPL), which helps burn fat.
• Too much sedentary time decreases bone mineral density without increasing bone formation, which raises the risk of fracture.
• Excess sitting increases blood pressure and decreases the diameter of arteries, both of which make heart disease more likely.
Even worse, too much sitting could shorten your life. Studies in the U.S., Canada, Australia and Asia have all found an association between increased sedentary time and the risk of early death. These associations were independent of traditional risk factors such as smoking, blood pressure, cholesterol levels, waist circumference and diet.
I'm sure this isn't news to you; most people are aware that physical activity is essential to good health. But what you may not know is that too much sitting time is harmful even if you're getting enough exercise.
This means you could be meeting the recommended guidelines for exercise (i.e., 30 minutes of moderate to vigorous activity, five days a week), but still be at higher risk of disease if you sit for long periods each day. In fact, a large study involving over 100,000 U.S. adults found that those who sat for more than six hours a day had up to a 40 percent greater risk of death over the next 15 years than those who sat for less than three hours a day. Most importantly, this effect occurred regardless of whether the participants exercised. Some research even suggests that people who exercise intensely (like marathon runners) are more likely to be sedentary when they're not exercising. They may assume that their training regimen protects them from the harmful effects of too much sitting when they're not exercising. It doesn't.
In industrialized societies, this "active couch potato" phenomenon has become the norm rather than the exception. If you work in an office, commute by car and watch a few hours of TV each night, it's not hard to see how you could spend the vast majority of your waking life (up to 15 hours!) sitting on your butt. This is far outside of evolutionary norms for humans, and has serious consequences for our health.