Updating its physical activity guidelines, the World Health Organisation on Wednesday urged citizens to stay physically active through the Covid-19 pandemic. A sedentary lifestyle may lead to another ill-health pandemic, the UN body said. Lockdowns and restrictions forced many people to stay indoors and disrupted regular activities, a trend which is worrying, the UN said. The world body estimates that pushing people to get moving could avert almost 5 million deaths a year. Adults must get 2.5-5 hours of aerobic activity a week while children should move an hour a day at least, they said. Sedentary behaviour, which has harmful effects, has been added to WHO guidelines for the first time.