RENEE ZELLWEGER has become an unofficial ambassador for underwear company Hanes after insisting the firm's pantyhose saved her life on the freezing set of her new film.

The actress shot New In Town with Harry Connick Jr. in Winnipeg, Canada, and admits the big freeze there took a lot of getting used to.

Zellweger explains, "I didn't know cold like that, it was a whole different kind of experience. I had to develop new survival skills. It was a whole new language for the biological things that happen.

"Who knew that pantyhose could be so very important - three or four pairs at a time. I never imagined that I would rejoice at the pantyhose laid out on the bed by wardrobe every morning. They were essential. I would not be here today were it not for the Hanes."

But, despite the big chill, Zellweger can't wait to return to Winnipeg.

She tells WENN, "We had a really good time. There were so many things about that place that were so charming. I loved the ice sculpture downtown. And I loved waiting for the snow to compile and harden - that took probably 30 minutes. That was fantastic.

"The tenacity of the people there was just so impressive. To me, you looked outside and thought, 'Where is the road?' - because you can't see the road. I'd think, 'I guess there is no driving today.' But that's not the case. Everybody just gets up and they get on with it like it's normal. It's just commonplace that your face freezes within two seconds of stepping outside of the door."