Tracy Anderson says consistency is key to staying slim during the Christmas holidays.

The celebrity trainer - who works with A-list stars including Gwyneth Paltrow, Jennifer Lopez and Kim Kardashian - advises women not slack with their fitness regime during the holidays and to keep exercising in order to avoid the January blues.

She exclusively told BANG Showbiz: ''Consistency is key. Through the holidays especially, it's really important that you're able to enjoy your friends, your family and food. You need to make sure that you are being consistent with your workout.

''This is the time to figure out how to make consistency part of your lifestyle so you don't end up owning 20 extra pounds of weight after the holidays.''

Tracy says sticking to natural, organic foods when making traditional Christmas dishes is the best way to enjoy the festive period while staying healthy.

She explained: ''The best thing that people can do is, try and make the recipes that you love without using processed foods. Try and make things that are natural and organic to bake with this year.''

The star believes the Xbox Fitness is the perfect way to work out at home over the holidays without disrupting all-important family time.

She said: ''A fitness program, asking for the Xbox for Christmas is a good thing to do. The new platform is so exciting and it's really great how it's all right there.''

Tracy has teamed up with Xbox Fitness, a new online service that takes the world's best fitness videos and makes them interactive with the power of Xbox One, personalizing your workout with instant feedback, smart recommendations and social challenges. It features an extensive library of videos from the world's biggest fitness brands, including Jillian Michaels, Tracy Anderson and Insanity.