On Monday, Josh Weinfuss of ESPN.com provided comments from Johnson, who said he felt overall health benefits during the three-week vegan lifestyle, but it diminished his abilities as a power runner.
"I'm not going to lie, my body felt great," he said. "I felt energized. I felt like my body was recovering, but I just couldn't keep the weight on."
Johnson, who's entering the final year of his contract, said he's worked with Cardinals strength coach Buddy Morris to regain his strength through a more balanced diet and weight training.
"I think I do feel a little bit better than last year going into camp," he told Weinfuss. "I think the biggest thing, though, is that I'm learning what to do to recover faster. I'm getting more massages, eating, maintaining the diet and really just figuring out ways to stay in shape."
The 26-year-old Tennessee native earned First Team All-Pro honors and a Pro Bowl selection in 2016 as he racked up an NFL-high 2,118 yards from scrimmage and 20 touchdowns.
He rushed 11 times for 23 yards in the Cards' opener against the Detroit Lions one year ago before suffering a season-ending wrist injury in the contest.
Now that he's healthy and back to his preferred playing weight, the dual-threat running back is hoping to put together his best season to date, per Weinfuss.
"It's good, but I actually want to be better than 2016," Johnson said. "I make my standard a lot higher than whatever everybody else is trying to compare me to. I think I can do a lot better than what I did in 2016, personally."
Johnson and the Cardinals kick off the regular season Sunday afternoon with a home game against the Washington Redskins at University of Phoenix Stadium.