I don't think training has anything to do with it. Of all teams, it is the Chinese teams that lay most emphasis on physical fitness, conditioning etc (the Japanese and Koreans are catchng up, though.) Even more, the girls/women are pushed even harder than the boys/men in this regard, and as kinda by default, expected to play twice as much longer as the men. There may be something else here. One thing could be the mental/psychological issues with any individual. Another could be the physical mismatches. Tall players are especially vulnerable to short players, or at least the more compact players who stay low to the ground and below the tape. Sun Yu may probably need another year or two with her coaches to sort out her issues with short and persistent players. She had beaten Noz in straights less than a week ago in the team championships. She needs to be able to answer different approaches taken by the same opponent; i.e., the adaptability factor.