I feel like this works for me once per day. Even if I take a break, the second study session is consistently less productive. Any thoughts on this?
Without asking a hundred clarifying questions... I suspect your third (or even fourth) cycle of studying might be more productive than the second. Mostly for food reasons but also circadian rhythm. Check out this image: https://www.semanticscholar.org/paper/The-post-lunch-dip-in-performance.-Monk/2a637623cc562fffcddf9aa8c41e41ef2069f3e1/figure/0
Porter S.