Sahin played just seven minutes of Dortmund's 17 matches before the winter break in Germany's top division due to his knee injury but the Turkey international is confident he will play a much bigger role in the second half of the campaign.
Dortmund will resume away to third-placed Bayer Leverkusen on Saturday with Sahin & Co. sitting second-bottom in the Bundesliga standings.
"I played seven minutes in the first half of the Bundesliga season. It was quite a new feeling for me to be injured for such a long time," Sahin said on Tuesday.
"For me personally the [winter break's] preparation was very important, I had to get my body in a good shape again.
"Now I am really looking forward for the second half of the season. I'm not afraid, on the contrary, I'm really happy to again be able to train every day.
"With my injury it was quite awkward, I wasn't able to get up on my feet so every minute I run is a huge gift now. So I train every day, I was able to participate in all the friendly games except for the one against [Steaua] Bucharest when I had some minor problems but, all in all, my body responds well to the training."
The 2014-15 German league campaign has been an incredible turnaround for Jurgen Klopp's men, who finished second last term.
But Sahin refused to get bogged down in discussions of what has gone wrong at the Westfalenstadion.
"I finished the year 2014 and the whole club and the whole team finished the year 2014. We are just looking forward for what 2015 can give us or what we can give 2015 and our fans and our club," the midfielder said.
"It wouldn't be professional to think about things that happened in the past."
