Shiel played just three games after round nine and none after round 17 last season, then had surgery in October in a bid to ready him for this year.
But he is no certainty to appear in the Bombers' season opener against Hawthorn on March 16.
"(My body) is getting better every week, which is good," 30-year-old Shiel said.
"It's been a slow, slow journey over this pre-season and off-season but fortunately I'm making some good ground.
"It's probably too soon to be rolling out to be playing just yet but we haven't got a hard time on it yet. We're just making sure that I can get the foot right, get the body okay so when I declare myself fit to play I'm ready to perform.
"If that's practice game, round one, great. And if it's not, well then we'll just have to take it as it is."
At his best, Shiel can be a linebreaking, dynamic midfielder.
"I believe I've still got plenty of football left in me," he said.
"That's why I'm still here. I'm still giving my best every day with everything I do with my training, in the meetings, even in my recovery and trying to help others get better as well around the club.
"Every year's an opportunity to play a career-best year.
"(Coach Brad Scott) has been really encouraging to guys taking that approach, even if they've been around for more of a decade."
Shiel said he was managing his training loads, making the most of an anti-gravity treadmill, and limiting time on his feet on days off, while he had to ensure he wore the right footwear and orthotics.
"You can't run on your hands, I've discovered," he quipped.
"You can't avoid the feet.
"I've been doing a mountain of work that doesn't get me too much credibility in the gym with how much weight I'm shifting but it's important work that I'm doing."
Shiel said he had been surprised when interest from St Kilda emerged last trade period - though Essendon insisted he was a required player.
"Yeah, there was the opportunity to move to the Saints, obviously that's been reported," he said.
"It would have been a more convenient drive from home, I live just around the corner from there. But fortunately, I'm still here.
"This is where I've always wanted to be. And I've been really clear with the club how committed I am to helping this club get to where it wants to be, and I'm excited."
9°C