Having already extended their reach into fashion, music, and so much more, the Kardashian empire is now tackling fitness. Khloe Kardashian is helping people change their bodies and lives in the trailer for Revenge Body with Khloe Kardashian.

The first look at the upcoming E! reality series opens with the youngest Kardashian sister discussing her own weight battle. “I was always overweight as a kid,” she admits. “If I was stressed out or sad, I would eat. So I then had to learn how to put my energy into something positive and healthy for me, which is how I fell in love with working out.”

Having changed her own habits, Kardashian and her team of trainers set out to do the same for others. Throughout the preview, the 16 participants realize how tough a transition they are making. “What the f— did I get myself into?” asks one competitor, echoing the sentiments of anyone who has ever made such a drastic lifestyle change.

While the journey is rough — “Either buckle down and take it serious or I’m just going to have to drop you and get somebody new,” Kardashian tells one woman — the participants realize there is a light at the end of the tunnel. “Who can legitimately say that their life was changed by a Kardashian?” asks one weight-loss hopeful.

Revenge Body premieres on Jan. 12.

Watch the trailer above.