Klopp, who replaced Brendan Rodgers as Liverpool boss in October, has promised his players a summer of hard work on the training pitch and will bring in a second member of Bayern Munich's backroom staff in pre-season.
“It will be triple training sessions, of course,” Klopp told British media.
“The problem with pre-season is that for the first three weeks we have 15 players who will have been away at the Euros and we also have to see how the squad is changing.
“On another planet we would have six weeks together training because in this league it is the only time that you can train.”
Liverpool head to the United States for a training camp in mid-July and will play friendlies against Chelsea and AC Milan, and Klopp said he would use the games to focus on building up his team's fitness.
The former Borussia Dortmund manager, who has already hired fitness coach Andreas Kornmayer Bayern, will bring in the Bavarian side's nutritionist Mona Nemmer in the close season.
“In all of the (pre-season) games we will play out full training,” Klopp said. “So if we play our best in pre-season then I've done something completely wrong. We have to do a lot to create a base for one year.”
Liverpool are eighth in the Premier League table with one game left and face Sevilla in the final of the Europa League on May 18. – Reuters
Original source: Klopp’s pre-season warning to Liverpool