A Melbourne west hospital has admitted to allegations junior doctors have been overworked, amid claims of exploitation taken to the workplace watchdog.

A Melbourne hospital has admitted to allegations of overworking its junior doctors amid legal action on exploitation claims.

Sunshine Hospital's trainee doctors, backed by the Victorian Australian Medical Association believe the hospital has been slamming the junior medicos with unpaid overtime and insufficient clinical training.

Western Health says it is making changes to reduce the workload of their junior doctors and provide them with adequate training opportunities.

"This includes improved rostered access to training time and the introduction of a new training time guideline following consultation with medical staff, as well as improved processes for claiming overtime hours," Western Health said in a statement on Wednesday.

The changes were only implemented after the trainee claims were made, but the health service is working "constructively" to resolve the issues, the statement said.

"The essential contribution of all medical staff, junior and senior, is greatly valued by Western Health which has recently implemented a range of measures to both reduce the workload on our junior doctors and to ensure access to adequate training opportunities during their time with us," the hospital said.

However, overworked and underpaid doctors is not an isolated issue, argues AMA Victoria president Julian Rait.

"It's not just isolated to Sunshine, but Sunshine has been, I suppose the source of the most complaints from our members and that's why we've decided to take Western Health and Sunshine Hospital in particular to the Fair Work Commission over this," AMA Victoria president Associate Professor Rait told 3AW on Wednesday.

"We're talking probably around about 64, 65 hours a week. So that's a significant amount of overtime probably about 24 to 26 hours on top of the usual week's work."

Metropolitan hospitals in Melbourne and larger regional centres suffer the most from overworked staff, Assoc Prof Rait argues.