Scarlett Johansson is a "stay-at-home-and-veg spice".
The 24-year-old actress admits she felt terrible watching husband Ryan Reynolds compete in the New York Marathon last year because she doesn't have the energy to do it herself.
She said: "I went to some random spot and saw everybody going past. It was really incredible. I'm a horrible runner - I can barely put one foot in front of the other.
"I saw that Jennifer Lopez did a triathlon and I'm like, 'Damn, girl, you just had twins!' It's amazing."
Referring to the nicknames the Spice Girls gave themselves - Posh Spice, Ginger Spice, Sporty Spice, Baby Spice and Scary Spice - Scarlett added:
"I'm so not a Sporty Spice - I'm a stay-at-home-and-veg Spice."
Scarlett also revealed she is keen to expand her acting repertoire and move away from period dramas, adding she would love to star in a Western movie.
She told Harper's Bazaar magazine: "Every actor wants to work on a Western. I would run a brothel, like a madam or something. I'm working with what I got. It's only so long that people are going to want to see me in a corset. So I might as well do it now."