Two years ago, I discovered that if I walked on a treadmill while studying Chinese flash cards, it became much easier. Without walking, I could barely study 10 minutes without getting exhausted and stopping. If I walked at the same time, however, I could study much longer — say, 60 minutes. Huge difference. Walking on a treadmill made studying Chinese pleasant. This was stunning because walking on a treadmill by itself was boring and studying Chinese (or any other dry knowledge) is supposed to be boring. I concluded that walking created a thirst for dry knowledge, which studying Chinese satisfied. My evolutionary explanation was that this linkage evolved to push us to explore our surroundings. My posts about this.
In an April 2012 QS talk, Jeremy Howard reported the same thing.
I discovered that if I am walking on a treadmill at 1.2 miles per hour at a 1 degree incline I have an error rate of about 5%. Whereas if I don’t [walk on a treadmill] it’s about 8%. I also know that I can do that for an hour. Whereas normally if I’m just sitting down I can just do it 20 minutes. . . . And at the end of that hour I was ready to do something else. Whereas at the end of 20 minutes, normally I’d [audience member: "Take a nap"] Yeah, I’d be totally ready for a rest . . I also discovered I was 40% faster [at learning].
He added, “I love my Chinese every day.” More recently, someone named Adam posted on the QS forums that he’d had a similar experience:
As Jeremy Howard mentioned in his talk, SRSing (is that a word?) is exhausting. Like him, after a period of about 20 minutes, I often reach a level of fatigue that makes it difficult to continue studying. I first read about the “treadmill method” on Seth Roberts’s blog & found it highly effective. Like Mr. Howard, I could study for hours without become bored . . . The only problem here is that I don’t have easy access to a treadmill. My gym is quite far & it is impractical to go there every day, while I desire to SRS every day.
That two other people noticed such a big effect is good reason to think that it will be true for most people.