The Rangers striker has been the target of critics who have written off his recovery from a second cruciate ligament injury.
He has also been forced to defend himself against accusations that he is in line to leave Rangers, but the 25-year-old Scotland star said: ''You have your doubters, people saying you will never be back. But I am fit and just about raring to go.'' Naismith, speaking exclusively to SportTimes, claimed he is set to return stronger and better to Rangers after being injured at Aberdeen in October.
It was his second cruciate injury – he was carried off in the 2007 Scottish Cup semi-final against St Johnstone – but he has no doubt he has been strengthened by adversity.
"The surgeon and the rest of the medical staff say a good eight weeks of pre-season will make me fit enough to resist anything,'' Naismith said.
He also revealed that recovery was easier the second time around. He said: "The rehab has been much more straightforward.
"The first time I would do an exercise and would feel a wee ache and would stop and the physio would reassure me.
"But in your head you would still be thinking 'Is that right?' This time I am comfortable. I know my limits, know what progress I have made.''
He added: "I got a lot of mental strength from coming back so well the last time.
"You get your first injury and it is very revealing. It tells you a lot about your life and yourself.''
Naismith, too, has been at the centre of the financial storm at Rangers. A lifelong fan, he has been saddened at the meltdown that has threatened to consume them.
He says the only upside of his injury was "it helped take my mind off the events at the club just a little bit''.
Naismith was one of the high earners who in March sacrificed 75 per cent of their wages so there would be no job losses among staff. But he has been at the heart of constant speculation about his future, with Rangers rejecting a bid for him from West Brom.
Asked about the doubts about where he would play his football next season, Naismith said: ''I am not in a state of uncertainty. I have certainty. I have a three-year contract.
"I have no say in who takes over the club or whatever happens in business terms, but I have a contract.''
He added: "It really is that simple. Now, I am not daft and things can change and I can have decisions to make. But then it will still be in my control.''
