The Abbott Government has asked the public sector to trim the fat and one agency is going above and beyond the call of duty, splashing out on fitness instructors to man its corporate gyms.

Airservices Australia is determined not to be part of a "bloated public sector" after putting out the call for instructors to help work the cores, abs and butts of its workers at gyms it provides for its staff in Melbourne and Brisbane.

While most government workers face lean times, increased efficiency dividends and stripped down budgets, Airservices' workers will be trimming down in their onsite gyms.

Bosses at the air traffic control outfit have decided that keeping the nation's skies safe is no job for the sedentary of lifestyle and the expectations on its new gym instructors are high.

Airservices' 4200 workers are not public servants and the Commonwealth-owned agency is not subject to the efficiency dividend but it has felt some of the icy blasts from Canberra after being asked in November 2013 to limit its hiring activities.

The agency is one of the federal government's financial success stories, reporting an after-tax profit of $63 million in 2012-13 on income of $955 million.

But the controllers' performance in getting to the gym has been less impressive; 575 of Airservices' 900 Brisbane workers have signed up as members, but they only managed about four visits, on average, in the three months until September 30, 2013.

The Melbourne office's cohort of 1100 has 643 gym members who also squeezed in about four workouts each at the office gym in the same period.

The gym and instructors are being offered to staff as part of Airservices'  "fit and well objectives".

"Airservices Australia aims to provide employees with activities, resources and education that will support and encourage health and wellbeing and positive lifestyle choices," according the tender documents for the contract.

The job is open to suitably qualified individuals or companies (Fitness Leader Certificate 3 qualifications or higher) who need to get their applications in before March 25.

This is not the public sector easy ride of popular imagination; the successful applicant has a tough program mapped out for them.

They will be expected to get physical, leading regular fitness classes working on cores, abs and butts, lung-busting circuit training as well as cardio and boxing sessions.