Melbourne: Czech powerhouse Petra Kvitova says her new fitness regime is helping her cope with the Australian Open heat after some previous blowouts in Melbourne.

Her last two appearances at the year’s opening grand slam ended in early defeats, but the Wimbledon champion looked in ominously good form when beating Germany’s Mona Barthel 6-2 6-4 to reach the third round on Thursday.

Despite winning a second Wimbledon title last year on the grasscourts that bring the best out of her game, her results elsewhere were patchy.

But with fitness coach Alex Stober, who used to work with the likes of 2014 Australian Open champion Li Na and Pete Sampras, in her corner working alongside coach David Kotyza she looks leaner and a yard quicker.

“I think it was quite warm today and I think I handled it quite well. The last two or three years I’m not sure if I can handle it like that,” the fourth seed told reporters.

“It’s always tough to breathe a little bit when it’s really warm. But because I had this time during the off-season I knew I could still play.

“When I knew today would be warmer than yesterday, I knew that [coach] David [Kotyza] was little bit worried. Me, too, of course. I did not say it.

“But I knew that I’m prepared better than the years before, I can handle it better.”

Kvitova began working with Stober in November and admits the off-season was a little more intense than usual.

“It’s my first time actually to have this combo,” she said. “When we started, the first three, four days was very, very tough. I felt everything. I couldn’t really walk. Was funny to see me probably.

“But I think that every day when he did the treatments, I could handle it more and could do tougher workouts. That’s helping me now.”

Kvitova, a semi-finalist in Melbourne in 2012, is up against hard-hitting young American Madison Keys next.