People often ask me what the difference is between training now and in the past.  It is hard to explain, the things that teachers complained about 50-100 years ago are the same things that they complain about today.  In the past, students seemed more focused, eager and dedicated, but that might just be sentimentality. Here is a video documentary of what it was like to train in Judo under the famous Judoka, Masahiko Kimura.  He trained eight hours a day even in retirement and into to his old age.  His osoto-gari (outside foot sweep) was said to be so powerful that it could give even high ranking black belts concussions and that he was even asked to not use it in training and was sometimes asked not to use it in matches.  There is a famous saying in Judo, "No one before Kimura, no one after."  He was one of the most prolific Judo players of our time.

Olympian Doug Rogers from Canada is the focus of this documentary about what it was like to train in Japan in the 1960s under Masahiko Kimura.

https://www.youtube.com/watch?v=CBFx1a4L2ig