Bayern won four trophies last season, but missed out in the Champions League after suffering defeat to Real Madrid in the semi-finals.
Lahm also had a successful summer with his country - captaining the European team to the World Cup trophy in Brazil.
"After I've had three weeks of vacation - I can say this now - I'm looking forward to being back with Bayern," he told Bild.
"Bayern always pursue huge goals."
Lahm open their Bundesliga campaign against Wolfsburg on August 22.