Depressed new mothers are being urged to push their prams - and beat the baby blues.
Medical researchers think regular pram pushing could combat the worst symptoms of postnatal depression, which affects more than one in ten women.
A team at Birmingham University is studying the effects of gentle exercise on a group of women suffering postnatal depression.
The mothers, including some who are already on anti-depressants, are being asked to push their babies in a pram for at least 30 minutes a day, five times a week.
They are being encouraged to walk instead of taking the car for the school run and shopping trips.
Dr Amanda Daley, of the university's department of primary care and general practice, said: "Around 13 per cent of new mums experience some form of postnatal depression and psychiatric illness is the largest cause of maternal death in the UK, so investigating the possibilities offered by new therapies is important."
Dr Daley said women suffering postnatal depression had problems bonding with their babies and the illness had a "massive impact" on the child and the wider family.
"These women feel depressed, low, that they have got the baby blues. They may feel they are not bonding with the baby, that they are not a good mother, that they are worthless and don't have good self-esteem.
"A lot of them will be over-weight, or feel that they are overweight, after giving birth. They may not feel very attractive."
Exercise is recommended for mild to moderate depression and it is believed a "moderate intensity" walk could help depressed new mothers.
As part of the 12-week trial period, the women receive two exercise consultations and support via telephone calls. Participants are also given a pedometer, which measures the number of foot steps a person takes, to help them monitor how far they walk each day.
Dr Daly said: "The women have been encouraged to be more active, particularly in terms of pushing their prams. If they are thinking about going out during the day, they should push the pram.
"We try and encourage them to do 30 minutes' exercise on five days of the week at a reasonable pace.
"We recognise that at the start not everybody will be able to exercise this much but at the end of the 12 weeks we would like them to be pushing towards 30 minutes, five days a week."
Asked what moderate intensity exercise meant, Dr Daley said: "Breathless, but not knackered."