Yogi: When the retreat started, the mind was really sleepy and went into chattering. There was aversion to it; it became very uncomfortable and the mind really wanted to go to sleep.
I couldn’t do much except to stand up and walk.
Sayadaw: When you saw the sleepy mind and it started chattering, right effort and wisdom had become weak and were not working actively anymore.
You should crank it up at the very beginning when you noticed it to inject more right effort or wisdom with right effort and try to activate the mind.
You’ll find yourself getting sleepier and sleepier if you fail to do this and you’ll get sucked into it. Yes, the right thing then is to get up and walk.
To activate right effort is to make the mind active somehow – you can try to increase the frequency of the awareness, body scanning for example and try to watch one spot at a time – head, ear, nose, mouth, sensations down the body all the way to the toes and working up. You can ask questions actively and continuously, like asking what you’re aware of.
You need to be creative to find ways to activate the mind and not just use the things I tell you. When you can’t change your mind, you change your body posture.