Policy specialists suggest that being two hours ahead of Greenwich Mean Time in spring would allow people to stay outdoor for longer, help them exercise more, and thereby make their lifestyles healthier. They want the UK to keep British Summer Time in winter. But psychologist Dr David Lewis said there were flaws in the idea.

Concerned by a recent survey that show trends of declining fitness and predictions that show more than half of the population becoming clinically obese, Dr Hillman, senior fellow emeritus at PSI proposes not putting the clocks back in October in one year, but still putting clocks forward in the subsequent spring.

This could put the UK one hour ahead of Greenwich Mean Time in the winter and two hours ahead in summer, known as Single/Double Summer Time, adopting the same time as France, Germany and Spain.

"The common reaction to the prospect of less daylight and sunlight when the clocks are put back at the end of October - signaling as it does the end of outdoor activity and the onset of a largely indoor leisure life - is a negative one," Dr Hillman writes.

"The additional hours of daylight would considerably increase opportunities for outdoor leisure activities: about 300 more for adults and 200 more for children each year, given typical daily patterns of activity."

Seasonal change

Studies reveal that people feel happier and more energetic during the longer, brighter days of summer. Moods often tend to decline during shorter, duller days of winter.

He concluded that adopting this proposal for a clock change is an effective, practical, and remarkably easily managed way to better align our waking hours with the available daylight during the year.

For the first time, British Summer Time was established in 1916 to give farmers more daylight hours to work in their fields. Scottish farmers have always been opposed to changing the current set-up because they would have to deal with an extended period of morning darkness.

Dr David Lewis, a chartered psychologist who has done research into the effect of sunshine on our well-being, says there are arguments for both sides.

"If people can be persuaded to get out more and exercise after school and work, they are more likely to do it if it's light, than if it's dark."

He noted that there is a danger that people leaving for work in the morning don't really wake up properly if it's not light. However, Dr Lewis also agrees to the idea of people finding more time to exercise, noting that exercising during daylight often elevates moods.

A Department of Health spokesperson said: "It is recommended that adults do 30 minutes of exercise five times a week and children do 60 minutes each day.