Ahh yes, the serenity of a shavasana.

That spell of meditation at the end of yoga practice when you close those peepers, soak up the darkness and let the stress slip away.

After a crack of dawn alarm call, frustrations of a cancelled train and a 6.30am start, a spot of extra shut eye would ordinarily be ideal.

But in The Sky Garden at the top of the Walkie Talkie zoning out in Dead Man’s Pose requires a tad more effort.

Because let’s face it – how many times do you lie back and finish a workout while staring at the puffy clouds filling London’s sky?

Sky High Yoga is the perfect way for early-birds to soak up the morning sunrise.

You might have to take the first DLR to lay down a mat on time but chances are you’ll be among a handful of bleary-eyed yogis on your journey, all heading to 20 Fenchurch Street for a most memorable fitness session.

The transformation from sleepy to super-awake happens the moment you enter The Sky Garden terrace.

Stunning panoramic views hit you from all sides including Canary Wharf’s towers, which were bathed in an attractive tangerine glow.

I faced the Gherkin and found counting its many windows was an ideal way to stay steady when you’re wobbling ungracefully out of posture.

The soothing music and green foliage help the “chittra vitti” style of Mona Heep’s session where you focus on the relationship between movement and breath.

The active toning and muscle-stretching sequences flow through the 60 minutes.

Only when you turn faces to the morning in warrior pose you realise night has passed, daytime has arrived and you’ve been doing downward dogs as the sun rises.

You’re 35 floors tall - and chances are your relaxation levels will soar just as high.

And for £10 every Wednesday , it’s a workout worth waking up for.

Starts 6.30am, 20 Fenchurch Street.

Two other places to try Rooftop Yoga

1. House of Voga at Coq d’Argent

The eatery’s rooftop garden plays host to yoga sessions on the last Sunday of each month. But this is yoga with a twist - with participants striking poses while a soundtrack from 80s plays out.

2. Rooftop Secret Yoga Club, part of Bold Tendencies building’s rooftop, Peckham.

Sessions are varied to cater for both beginners and more experienced yogis.

Cost £12 each.