Spending time online is normal behavior for teenagers. But too much Internet use by teens -- or too little, for that matter -- might be related to depression, a study finds.

The findings, reported in the journal of Pediatrics, do not mean that the Internet is to blame. For one, teens in the study who spent no time online were also at increased risk of depression symptoms.

Instead, the researchers say that both heavy Internet use, and non-use, could serve as signals that a teenager is having a hard time.

For the study, Dr. Pierre-Andre Michaud and colleagues at the University of Lausanne, Switzerland, surveyed 7,200 individuals ages 16 to 20 about their Internet use.

Those who were online more than two hours per day were considered "heavy" Internet users, while those online anywhere from several times per week to two hours per day were considered "regular" users.

The teenagers also answered a number of health-related questions, including some standard questions about "depressive tendencies" that gauge¹ how often a person feels sad or hopeless.

Compared with regular Internet users, the study found, kids who were heavy users or non-users were more likely to be depressed² or very depressed.

Among male teens, heavy users and non-users were both around one-third more likely to have a high depression score, compared to "regular" users. Among girls, heavy Internet users had an 86 percent greater chance of depression, while non-users had a 46 percent greater likelihood compared to regular users.

Getting up from your desk to go and speak to your colleagues – instead of emailing them – reduces the risk of heart attacks, research shows.

Those who take short breaks away from their seats – lasting³ as little as a minute – at regular intervals⁴ throughout the day are less likely to be overweight and have high blood pressure.

They also substantially reduce the risk of potentially fatal cardiovascular diseases.

Researchers found that people who are on their feet for short periods which add up to more than two hours a day tend to have smaller waists and lower blood pressure.

They studied the habits of 4,757 adults over the course of a week.

Each participant wore an accelerometer, a small device fitted to the hip⁵ to measure how much time they spend walking and running.

Their waist size, blood pressure and the level of C-reactive protein in their blood, which is often high in people at risk of heart disease, were also measured.

The researchers, from the University of Queensland in Australia, whose study is published in the European Heart Journal, found that those who took the most breaks had waists up to 4cm smaller than those who were more sedentary.

研究显示，起身离开你的办公桌去和同事交谈，而不是给他们发电子邮件，可以降低患心脏病的风险。

那些每隔一段时间就起身稍微休息一下的人，哪怕只有一分钟，他们体重超标或者患高血压的可能性也会较小。

这些人患上致命的心血管疾病的概率也会小很多。

研究人员发现，如果你每天多次起身且累计每天站两个小时以上的话，那么你的腰会更细，血压也会更低。

研究人员研究了4757个成人一周的工作习惯。

每个参与者都在胯部佩戴了一个加速表，这个小装置是用来测量被调查者每天用于走路和跑步的时间。

研究人员还测量了参与者的腰围、血压以及血液中的C反应蛋白含量。一般心脏病患者的这些指标都很高。

这些来自澳大利亚昆士兰大学的研究人员发现，那些经常起身活动的人的腰围要比久坐的人腰围小4厘米。该研究发表在《欧洲心脏杂志》上。