Alastair Cook said his lean summer spurred him on to his prolific Ashes series.

The 26-year-old scored 189 in the fifth Test, taking him to 766 for the series, as England moved into a commanding position in a match they need only to draw for a first Ashes victory in Australia since 1987.

England made 488 for seven, boosted by Cook's ton and 115 from Ian Bell - his first Ashes century - to end day three at the Sydney Cricket Ground with a lead of 208 runs.

Asked what has motivated him this winter, Cook, who has batted for 2,171 minutes in the series, said: "When you don't score runs.

"I spent a lot of last summer not scoring runs. It's pretty lonely.

"When you don't get any for a while, then you find form, you've got to make the most of it."

On his concentration and stamina, Cook added: "You can switch off a little bit at the non-striker's end.

"When you're batting well you get into a rhythm, you don't get flustered. Suddenly an hour goes, it's drinks and you don't know where it's gone.

"(I do) a lot of hard work in the gym. I'm lucky I don't sweat, I don't get too hot, and I'm pretty fit.

"(With) my technique, I've gone back to what I started with. We've got a great set-up here.

"We've got great confidence in how we've been playing over a period of time."