Pippa Middleton’s wedding diet and exercise regimen is so intense! A new report has revealed just how Kate’s sister is getting ready for the big day.

Middleton has been kicking up her workouts at the KX Gym in Chelsea before she gets married on May 20. She recently attended a 75-minute Pilates class. And sources told E! News that Middleton looked “excited, happy and smiling.”

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Of course, Middleton has always stayed incredibly fit. She even climbed the Swiss Alps for charity last April. Middleton has also participated in the Inferno race in Switzerland and the Birkebeiner Ski Race in Norway.

Pippa Middleton and James Matthews Pippa Middleton and James Matthews did the Birkebeiner Ski Race together (Photo: Splash News).

Middleton is also staying healthy by sticking to the SirtFood Diet. According to E! News, KX Gym even has a restaurant with a SirtFood Diet-friendly menu, which works out great for Middleton.

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The SirtFood Diet, which Adele also subscribes to, emphasizes foods with high levels of sirtuin-activating nutrients. These foods include arugula, red wine, cocoa, coffee, kale, strawberries and walnuts. They will increase your metabolism and your ability to burn fat.

“There is no one who will not benefit from following it,” trainer Pete Geracimo previously told E! News of the SirtFood Diet. Geracimo also helped create it.

Pippa Middleton Diet and Exercise Pippa Middleton has always been very fit (Photo: ISP / Splash News).

Pippa Middleton also previously shared her diet and fitness secrets in a column for Waitrose Weekend magazine. She wrote that she worked with a nutritionist and personal trainer. She limits her refined carbs, practices portion control and exercises three to five times a week. Some of her workouts include ladders, plie squats, wall pushes, and the plank.

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“I grew up with the belief that good health is all about moderation in all things, so I’ll be celebrating healthy living through exercise, a balanced diet and a little naughty stuff sprinkled in – I’m talking chocolate, crisps, and the occasional glass of wine,” she previously wrote.

Would you try the SirtFood diet? Let us know your take in the comments section below!