A lot of studies have shown that over a certain level, increased time leads to decreased productivity. The studies have usually been done relative to work, demonstrating that between 50 and 70 hours of work there is only a minor increase in total produced, and after 70 hours a week there is actually a decrease in total produced, according to one such study that I saw recently. However, given that accounting work and accounting study are similar, I think that sometimes the same principal applies if you combine the time spent at work and the time spent studying. So, that's not to say that if you work 50 hours a week, you shouldn't study at all; however, if you work 50 hours a week and study 20 hours a week, that still leaves around 30 hours a week open, assuming you sleep about 8 hours a night, and allowing around 2 hours a day for showering, driving to work, eating, etc. So, the other 30 hours a week could be devoted to studying, pushing the total accounting hours for the week to around 100, but I don't think the gains are worth it. Instead, taking at least part of that time to relax, pursue a hobby that helps restore your mental health, spend time with family, etc., is probably more valuable to your productivity than to spend it all in studying.
Everyone's limits are different, so I'm not saying that none of those 30 hours can be spent studying. However, I am saying that at least part of them can be spent non-studying. Some people might need to spend 20 of them devoted to family obligations (if they have kids, or aging parents, or other family obligations), so only have 10 left to determine how to spend; others might have all 30 up for negotiation. If you learn to listen to your body and evaluate the effectiveness of your study, I think that you'll find that some breaks can contribute to much improved study when you do study.
On the flip side, you've got to make sure that the study time you do have is effective, in order to have time to take breaks. If “study time” really means “browsing Another71 time”, that might not allow time for breaks to pursue more enjoyable things. However, I know you've posted a lot about the promodoro technique, so I think that you're familiar with how to make study time effective. Now you've just got the practice the part of the theory which involves rewarding yourself with breaks, and pick something fun to do on those breaks. 🙂
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