If you have your camera set to continuous record like I do, the camera simply records 1 minute video for every minute regardless of motion, like you’re saying. If you set it to record events only, it saves any 1-minute video to your SD card regardless of when within that minute the motion occurred. So as long as there is motion within any minute, that 1-minutes is saved.
Now, there is some discussion on how much motion is required to trigger a save. But that’s another issue.