The 'Blue Samurai' had 11 Europe-based players in their squad of 25 for the just-finished Kirin Cup, with strikers Takashi Usami and Tadanari Lee set for moves to Germany.
Shinji Kagawa, reported to be a target for Manchester United, was left out as he is still recovering from a fractured metatarsal suffered while helping Japan win a record fourth Asian Cup in January.
Midfielder Yasuhito Endo of J-League side Gamba Osaka said Zaccheroni believed Japanese players had to play abroad to take their abilities to a new level.
"I've heard all about Italy from the coach," Endo told Thursday's Nikkan Sports.
"I leave those things up to my agent but I'm not the only one getting that sort of advice from the coach. He wants us to be playing at the highest club level."
Zaccheroni, who played a key role in full-back Yuto Nagatomo's move to Inter Milan, wants all his players to have the same conditioning when they meet up for Japan duty.
"Unlike at club level there's only a limited period when they come back for Japan games," said Zaccheroni. "Because of the different schedules of the European and J-Leagues their conditioning is all over the place.
"I want them all to be at the same level when they're on international duty."
