Hazard joined Real from Chelsea in the summer for an initial £88.5million fee which will rise to £130m with add-ons.
Wenger has suggested the Belgian began the season overweight.
But Hazard told Sky Sports: "For the last month I've been in good condition with no injuries.
"I'm in good shape. When I'm on the pitch I will always try to do my best, with Real Madrid or Belgium. I just want to keep this momentum."