`I had been running' is an example of the past progressive.
Examples of past progressive
past progressive
Like the present progressive, the Italian past progressive is extremely regular.
From the en.wikipedia.org
The past progressive is considered interchangeable with the imperfect.
From the en.wikipedia.org
The past progressive construction indicates ongoing action in the past, and is sometimes called the past continuous.
From the en.wikipedia.org
And, I also, recognize the GOP has embraced progressive thought in the past.
From the swampland.time.com
To convey the past perfect progressive in the passive voice, the construction It had been in the process of being written can be used.
From the en.wikipedia.org
In response to interrogatives, Dili is used to reply negatively to future actions, while Wala is used to reply negatively to past and progressive actions.
From the en.wikipedia.org
Accountancy firm Collins SBA principal Sean Devenish said the idea of the reclusive accountancy geek was valid in the past, but progressive firms are changing that.
From the couriermail.com.au
Some business leaders are more progressive and inclusive than in the past.
From the kentucky.com
But in the past 15 years, two progressive kings have invited French winemakers to lease prime land, and a wine industry has begun to flourish.