Only upload files idle more than 1 minute

Is there a way, when scripting an upload via PowerShell/etc., to only upload local files that have been idle for a certain period of time? (ex: idle for more than 1 minute)
Thanks,
Todd.

What does it mean when "file is idle"?
You can upload files that were not modified in the last one minute by using a file mask with a time constraint: <1N

Cool. Thanks Martin, I believe that's exactly what I'm looking for.
To only upload a file that has not been created/modified in the last minute or two.