"If I would have played less, I wouldn't be here at the Finals,” Thiem told reporters at the ATP World Tour Finals in London. “This was one of the reasons why I'm here, because I was playing a lot ... Maybe I will play a little less, but also maybe not. I think, also, the body and the mind and everything gets used to it. It was my first year that I played over 80 matches. Of course, I drop a little bit.
"I think it's really normal. I think that if I play the same amount of matches and tournaments next year, I will be used to it much better than this year."
Thiem, who has lost to Novak Djokovic and beaten Gael Monfils in London, plays Milos Raonic on Thursday in his final round-robin match. The winner will advance to the semifinals.