Pippa Middleton has hailed her Pilates sessions as a "weekly necessity".

The 27-year-old brunette - who showcased her enviable physique at last month's Royal Wedding between her sister Kate Middleton and Britain's Prince William - has revealed the secret behind her stunning figure is regular trips to Pilates classes at a small studio near her West London apartment.

In a testimonial on the unnamed fitness centre's website, she wrote: "From breathing techniques, muscle toning to overall flexibility and relaxation, my Pilates sessions have become something of a weekly necessity that keeps me fit, happy and energised."

Pippa - who has become an internet sensation following her international debut at the royal nuptials and even has a Facebook group with tens of thousands of members celebrating her behind - admitted the calming routines have also been a "wonderful escape" from her "busy lifestyle" in London.

She added: "As someone who is always on The Go, Pilates has been a wonderful escape from my busy lifestyle in London. Whether it's 7am in the morning or 7pm at night I always leave feeling calm, refreshed and invigorated.

"Over the past few months I have noticed a huge difference in my core strength and posture and couldn't recommend Margot more highly as an instructor."