No date has yet been set for the 27-year-old's return to action but former Ireland strength and conditioning coach Mike McGurn has suggested he will struggle to stay injury free in the future given his combative style of play.
Ferris admits that he was frustrated and somewhat surprised by McGurn's comments but he insists we will see him at his very best before the Lions head to Australia this summer.
"People can say and write what they like, but at the end of the day they don't know me," said Ferris.
"Reading that article, it didn't make me angry, but that is somebody that I've worked with and I think he should have kept his opinions to himself.
"That's my opinion and I know a lot of other people who share that opinion.
"I'm the strongest I've ever been in the gym and personally I feel absolutely fantastic, so I just can't wait to get back out there.
"When I do get back out there, I think I'll be better than I was when I left off."
So what exactly did McGurn say about Ferris' future? Well, he picked up on the star blindside's chequered injury history and claimed that an early retirement was likely to come his way unless he developed his game to focus on other potentially less damaging areas.
"He's a really combative player, but unless he changes his style of play - which would be hard for him to do at this stage of his career - and avoids some of that contact, there's not going to be much longevity," said McGurn, who coached rugby league outfit St Helen's before being headhunted by the IRFU and Eddie O'Sullivan.
"Stephen is naturally powerful. He was born that way and he has enhanced that power in the gym. Because he is so powerful, he is creating a lot of stresses on his joints - ankles, hips and knees. So it's just a matter of the body not being able to handle the freakish pressure that he is putting on those joints.
"The human body wasn't made to do what Stevie gets it to do on the rugby pitch. Your bones can be as strong as you like, but your tendons and ligaments can only hold you together for so long and that's where he's damaging himself.
"He's a smashing lad and he does a great job. But will he change his style? Personally I doubt it because that's what makes him tick.
"If he does, that might give him an extra three or four years, which is what we'd all like to see for him because his career really has been disrupted by injury.
"Pound for pound, he and David Wallace are the two hardest I worked with. And what happened to David? (He retired with a knee injury.) Exactly. The same as could happen to Stevie - injury after injury until finally the body can't take any more."