Speaking to Warriors TV, James said: "The ankle injury against Ulster was definitely frustrating, coming when it did. I've had a good amount of time to get fit though, so it's feeling really good.
"Pre-season has been good - we're stepping up the intensity week on week. We've been building up a good fitness base, and we're starting to bring in more rugby related skills so it's going well.
"It's hard to replicate a game week, where you've got a real spike at the end. The way we're doing it is going above and beyond what we'd experience in a regular season."
The Glasgow squad are adapting to a new coaching set-up, with Gregor Townsend having departed at the end of last season. However, the hooker is enthusiastic about the impact the new coaches have had in pre-season.
"It's change, it's certainly different," said James.
"They [new coaches Dave Rennie, Jason O'Halloran and Jonathan Humphreys] are trying to instil a slightly different game plan to Gregor, so it's exciting. It's new, so it's about trying to adapt and get comfortable playing that way.
"Monday, Tuesday, Thursday and Friday all follow fairly similar structures - in the morning we'll have a skill development period, followed by a gym session and a rugby session. After lunch it's another rugby session, and that's the real hard, fitness-based session."
James has been involved in the Warriors professional environment for two seasons, and as well as benefiting from the knowledge of more experienced team-mates, he's also able pass on wisdom of his own.
He added: "It's definitely motivating, having some of the top guys in the country in your position. You want to push on, as well as get as close to them as you can.
"It's only a couple of years ago that I left the academy, so I've been in the same situation as the young boys. I'm always happy to lend a hand if they need it."