You might do better if you tried a few simple learning techniques.
Research shows lying down is the poorest position for learning.
Sitting up is much better. Standing while learning is better still. And walking while learning is best of all, provided you're in familiar territory and don't stumble over anything. And if you are firmly gripping something while in any of these positions, they you increase the level of learning for that position. So the best position would be to walk while gripping your book.