I usually try to do the pomodoro tecnique, 25 mins of study, 5 mins rest. Between your breaks you can have some hot salsa by your side or do some stretching, sit ups, some thing to get you going. Hope this helps. I wish you the best in your studies.
I try to study in 15-20 minute intervals. Stand up, walk around. Think about what I read or listened to. Mostly, if I embrace what I am learning, with passion, fatigue takes much longer to surface.
I take a break, eat an apple or a banana, and some almonds. And by break I don’t mean looking at my phone, I mean going outside and take some fresh air for 5/10 minutes.
When I’m studying or learning something new, I take the time to process and comprehend what it is before I move on to something else. Repetition is the key so Ill simply ponder and reiterate what I’m learning in different ways so that I gain understanding.