I'd call it either a reduced adverbial clause or a nonfinite adverbial clause, depending on whether my audience was using a system that required finiteness for clausehood.

---- Bill Spruiell

From: Assembly for the Teaching of English Grammar [mailto:[log in to unmask]] On Behalf Of Scott Woods
Sent: Wednesday, April 20, 2011 1:42 PM
To: [log in to unmask]
Subject: grammar question: "while running"

Dear List,

How would you analyze "while running" in the sentence below?

 I yelled a command while running.

Thanks,

Scott Woods
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