Junior doctors have been known to clock up 100 hours in a week without a rest.

Under new European regulations, which became a reality for trainee doctors this month, they should no longer be working more than 58 hours a week.

Although this has been welcomed as a triumph by doctors they are also saying it could be quite restrictive.

Hannah Tomes, 25, is junior doctor representative at Warwick Hospital.

She said: "We have been redesigning rotas to deal with this. It can make it incredibly difficult when some guy miles away from us comes up with the idea to cut our hours.

"The reality is we are not necessarily seeing an influx of doctors to fill in the time.

"It's quite difficult to stick to these hours. If someone is acutely unwell you cannot just say to the relatives 'it's 5 o'clock, I'm going home'."

By decreasing the hours Dr Tomes said this was not decreasing the workload on junior doctors as no more staff were being called in.

But she welcomed new regulations but said it would take a while for people to get used to the changes.

The new rotas could mean mean doctors would no longer be on 24 hour call. At the end of their shift they would be able to hand over their wordload to the next doctor starting a shift.

John Boileau, workforce development manager for South Warwickshire General Hospitals Trust, said doctors had been campaigning for shorter hours for many years.

He said: "The whole point of these new regulations is to improve working lives. Often this can seem difficult because some people do not like change."

Hospitals face fines if staff work over their quota of hours but Mr Boileau said it was all about understanding and a doctor could not leave their patient in the middle of consultation or treatment.

It is hoped by August 2007 the hours will be reduced to 56 a week and by August 2009 to 48 hours.

Mr Boileau said: "The directive is not flexible. We are trying to tell our doctors to go home at 5pm when their shifts have ended.

"These changes are very overdue but it would have been nicer to have a little bit more flexibility."

The directive also means that doctors must have a 30 minute break every four hours.