<p>^ While you can say that, I don’t think it would be appropriate for the tense in the sentence. The sentence is in the past tense, and had been running I don’t think is really used in English. I think usually when you use a verb ending in -ing it has to do with an event that is happening right now in the present and is ongoing. I don’t think “had” is usually used with -ing verbs. More common would be something along the lines of “He has been running for a while now.”</p>