Chinese people are sleeping later on average than they did 10 years ago, but their total sleep time remains the same, research by the Leisure Economy Research Centre of Renmin University shows.

A survey on 2,000 people of all ages and different fields shows people, especially 25 to 45-year-olds, tend to sleep 40 minutes later than 10 years ago.

The survey listed 24-hour television, overtime work, increasing demand for education, and in particular, the spread of Internet as reasons for sleeping later.

However, the total sleeping remains the same at an average daily eight hours and 41 minutes and one hour longer on days off.

The widespread use of household appliances has lightened the burden of housework, allowing more time for rest. Meanwhile, more people begin working at 9:00 a.m., one hour later than 10 years ago, which enables people to maintain their sleep time, according to the survey.

Professor Wang Qiyan, of Renmin University, who has studied sleep for more than 20 years, said, "Good sleeping habits and reasonable sleeping period are beneficial to health and work efficiency.

"If late-sleepers regularize their sleeping period and ensure six to seven hours every day, their health will not be affected," he said.