hit the ground running

hit the ground running (be able to work effectively when you begin a new job; to begin a venture with great energy, involvement, and competence; to begin or proceed quickly, energetically, or effectively;to start doing something successfully without any delay) — взяться за / начинать дело без раскачки, без проволочек; энергично взяться за дело; взяться за дело с энтузиазмом; взяться за что-л. в полной боевой готовности (контекст)
This is about being ready, especially for a new task.
' ready to come to grips with their jobs'

...We need the new management team to hit the ground running if we want to reach our financial goals.

...Law graduates are expected to hit the ground running.

...The new work year has started, and I had to hit the ground running this week. So many things to do in the first week, whilst most others are still on half load, I already feel like I’m going to slide under my table and rot.

...Following her second year of law school, Marcia Owens hoped to hit the ground running as a summer associate: doing real work for real clients on real deadlines ...

Leaders' Edge: Hiring graduates who can hit the ground running.

to immediately work very hard and successfully at a new activity.
.....If elected, they promise to hit the ground running in their first few weeks of office.

to be ready to work immediately on a new activity.
.....His previous experience will allow him to hit the ground running when he takes over the Commerce Department.

see also
[get off to a flying start]