To set the quote into context here's an excerpt from Hard-Boiled Wonderland and the End of the World by H. Murakami.
There was little left to do but lean up against a wall and count the change in my pockets. For someone in my profession, know how to kill time is as important a method of training as gripping rubber balls is for a boxer. Although, in any strict, it's not killing time at all. For only through assiduous repetition is it possible to redistribute skewed tendencies.
I would interpret as it takes lot of effort (assiduous repetition) to replace (redistribute) bad habits (skewed tendencies) but it's does not seem to fit here.