A 7am start and 3pm finish would avoid the after-lunch slump into 'sluggishness, sleepiness and forgetfulness' that 38 per cent of workers admitted to in a BT survey.
It found an earlier working day would make many people, especially women, more efficient. Forty per cent of those interviewed said they were at their best in the morning, while only one in four considered themselves 'afternoon' types. Just one-third felt they were 'evening' people.
Although women are more likely than men to feel energetic in the mornings, one in four feels 'lazy' by mid-afternoon. Towards the end of the day, nearly two-thirds of women have slowed down compared with just 50 per cent of men.
Half of the 1,037 people questioned said they would like employers to offer more flexible hours to accommodate their 'best time of day'. One in five would even be prepared to take a pay cut to work their preferred hours.
BT commissioned the survey to mark the abolition from Wednesday of its morning peak rate - the latest move in the telephone price war. Morning calls will be charged at the same rate as the slightly cheaper afternoon calls.