Gladbach impressed in the first half of the campaign and entered the mid-season break in fourth place - which would be enough to enter the Champions League qualifiers - with 27 points from 17 matches.
However, just five points separate Bayer Leverkusen in third from Eintracht Frankfurt in ninth in what is shaping up to be a close-fought race to qualify for Europe's premier competition.
"The start of the second half of the season is super-critical," Kramer told Bild. "It's all so close up there.
"If you mess up, you can quickly be gone. But we are well prepared."
Gladbach are also challenging in the DFB-Pokal and UEFA Europa League and striker Max Kruse feels their hard work during the break will ultimately bear fruit by the end of the season.
"Our preparation has been awesome," he said. "We have worked like never before. The suffering will be worth it. We have more than many other clubs."
