Anderson returned match figures of 1 for 97 at Emirates Old Trafford, saying on Monday that he had "not bowled very well" and "felt out of rhythm" during the first Test. Over the course of the summer, he has taken six wickets in three Tests at an average of 41.16.
And while Anderson dismissed speculation that his retirement is imminent, he admitted: "If I keep bowling the way I did this week, the opportunity to retire will be taken out of my hands - it will be a selection issue."
But in his pre-match press conference, Root said that it would be "very silly for us to write someone like Jimmy off," and said that he expected "to see the best of him again very soon".
"To question Jimmy's ability and his record - do that at your own peril," Root said. "There's a reason he's got so many wickets over such a long period of time: it's because he's a consistent performer. I don't think it'll be long until he's back in the wickets big time.
"I think it would be very silly for us to write someone like Jimmy off. He's still as dedicated as ever, he's working very hard at his game, and looking very good in practice. I don't think it'll be long before he's got another five-for to his name."
Root said that he had sat down with Anderson during the first Test, and that getting his concerns about his form with the ball off his chest had been helpful.
"It just shows that even the greats of the game have those days where it doesn't always come naturally, where it doesn't always feel like the easiest game in the world and you know it can be a real struggle sometimes," Root said. "That's the way it goes and I feel with Jimmy we know it won't be long before he's back at the top and at the peak of his powers and I'm very much looking forward to seeing him perform this week.
"Sometimes it's very easy just to look at the statistics and not have a more broad view on how things are actually going for you. Sometimes you create pressure and wickets come at the other end and you build a partnership that way.
"There have been occasions this summer when that's been the case for Jimmy. Wouldn't you give him the opportunity [to put things right] with almost 600 Test wickets under his belt?"
England named a 14-man squad for the second Test, and will make at least one change to the side that won in Manchester. Ben Stokes will be missing the final two Tests due to family reasons, with Zak Crawley set to slot back in at No. 3 and Root shifting down to his preferred No. 4 role.
Sussex seamer Ollie Robinson has been included in the squad for the second time this summer, but appears unlikely to play. Root confirmed that Mark Wood has been suffering from "a knock" in recent weeks, and that England needed to make sure he was "absolutely 100%" before picking him, but said that he had bowled with "high pace" in training on Wednesday.
Root also admitted that he would like to see Jofra Archer bowling at 90mph "for slightly longer periods of time", but said that he and the England management accepted that "it's not going to happen all the time".
"He's going to go through phases where he's not always operating up at 90mph," Root said. "All we can ask of Jofra is he keeps putting it in - keeps showing the desire, the want, the hunger to keep getting better, day in, day out.
"We know there's more to him than just bowling fast. But obviously it's a great point of difference to have when you've got someone that can bowl at those speeds. If he gets the opportunity to get out there and show everyone what he can do, [bowling fast] is one of his great assets, so it would obviously be good to see him operating there for slightly longer periods of time."
England squad for second Test: Joe Root (captain), Dom Sibley, Rory Burns, Zak Crawley, Ollie Pope, Jos Buttler (wk), Chris Woakes, Sam Curran, Dom Bess, Jofra Archer, Stuart Broad, James Anderson, Mark Wood, Ollie Robinson