TOKYO (YOMIURI SHIMBUN/ASIA NEWS NETWORK) - The federation of senior citizens' clubs in Nonoichi, Ishikawa Prefecture, launched a campaign two years ago called "Stand Up 301," which encourages the elderly to get up at least once every 30 minutes, in cooperation with the city government.

At club meetings, they encourage members to stand while speaking, and also call for periodic standing and stretching at lecture events for the elderly.

"We have been working on making the project well known at each senior citizens' club, and it has also begun to be practiced at household level," said federation chairman Hiroshi Nishimura, 76. "More people, who previously did not get out very often, are showing up at the meeting venues now."

As people get older, they tend to sit for longer periods of time, and the time spent watching TV is an indicator of the length of sitting time.

The efforts are also gaining attention from companies because of a link between less sitting time and improved productivity.

According to an NHK Broadcasting Culture Research Institute survey, TV-watching time increases with age.

In their 60s, men spend three hours and 59 minutes watching television each weekday, while women spend four hours and 21 minutes. In their 70s and above, those figures increase to five hours and 16 minutes for men and five hours and 29 minutes for women.

Concerns that excessive sitting can lead to "economy class syndrome", or deep-vein thrombosis, and other negative health effects have been raised for a long time.

The mechanisms at work are not yet completely understood, however, as Ms Yuko Kai, a senior scientist at the Physical Fitness Research Institute, Meiji Yasuda Life Foundation of Health and Welfare, pointed out. "When we do not move the large muscles in the lower half of the body, this inhibits the absorption of blood sugar into the muscles," Ms Kai said.

As the levels of blood sugar and triglycerides rise, the risks of ailments such as diabetes and cardiovascular disease increase.

Companies have begun to take serious action in recent years to address excessive sitting by their employees. Such efforts have been fuelled by increased concern about the negative effects on productivity caused by health problems.

In the head office of Rakuten, in Setagaya Ward, Tokyo, each employee's desk can be altered to their preferred height.

The office uses standing desks that can be adjusted up and down with electric motors, and while some employees sit in chairs and read documents, others stand up to work on their computers.

Ken Mukai, 25, who works in Rakuten's Human Resources Department, raises his desk and works on his feet at times such as when he gets sleepy after lunch. "I feel fresh and can focus," he said.

In 2015, the company introduced about 13,000 standing desks for its entire workforce, including employees of its overseas offices, with expected benefits on improvements in both health and productivity.

"It frees us from working in the same posture for a long time and even promotes freer thinking," a Rakuten employee said.

Fujikura, a Tokyo-based electrical wire manufacturer, has also introduced standing desks.

"We have adopted them as a management strategy. Creating a sustainable healthy environment is not a cost, but an investment," said Mr Kenichiro Asano, deputy manager in charge of health management promotion.

Ms Kai said: "Excessive sitting has negative effects on both the mind and health... Standing is easy to do wherever you are, and I expect we will see more and more of such efforts."