The way of learning of Rav Nahman was to say the words and to go on. And not to do any review until one has finished the book one is learning until he or she has finished it. Then to review again and again. This comes up in the Conversations of Rav Nahman 76. But it is also brought in his Magnum Opus {the LeM}.
I suggest applying this to things that are beyond the general accepted Torah sessions. --To include Physics and Mathematics. The reason I say this is more or less based on the Musar book The Obligations of the Heart and the Rambam. These Rishonim saw in natural science and Metaphysics an imperative. To the Rambam, Physics and Metaphysics are included in the commandments to love and fear God.
However, it is true that most people that are good in these subjects have IQs that are way beyond us regular people. So my point here is not that everyone can be a genius at these subjects-- which I realize are difficult. It is rather that everyone has access to these subjects --even though they might think that they do not. And these access is through this path of learning fast--saying the words in order as fast as possible and going on to the end of the book--and then tart again.
[In Far Rockaway, Rav Freifeld emphasized review of every chapter 10 times,- but I found that did not work very well for me. I whittled it down to review twice of every paragraph. But when it came to math and Physics, I found the only thing that seems to work for me is this path of learning of Rav Nahman.]
[However, even with Rav Nahman, there is a place for deeper learning [as he also mentions in Conversation #76] [And the Le.M VOLUME I chapter 74]. So when I try to learn Gemara, I do try to spend a little more effort into the deeper aspects. But when it comes to Physics, I find that efforts on depth tend to take away the time I need to get the big picture. So there I tend to concentrate more of Rav Nahman's path of just saying the words and going on.]
Just for a reminder "outside wisdoms" are not books on natural science, but as the Rif [Rav Isaac Ilfasi ] and Rosh [Rabbainu Asher] explain they are books that explain the Torah in other ways besides the Sages of the Gemara.[You can find this idea of the Rif in the first mishna in chapter Helek in Sanhedrin]