Newcastle United have been linked with a move for the France international midfielder, who has claimed he has a knock and is not seeking a move.
Grenier posted on his personal website: "I have read a lot of things about myself recently.
"Just to be clear, Lyon's medical and technical staff have set me a specific programme so I can be back at 100 per cent.
"That includes a period spent training indoors. That is why I have not been present at some of the training sessions.
"I have no problem with the club and have never missed a training session intentionally.
"There is no controversy and my intention is to be back on the pitch and competing as soon as possible."
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