Tumble will pit celebrities against one another as they learn gymnastics before being judged by London 2012 Olympic medal winner Louis Smith.
Former The Only Way Is Essex star Lucy tweeted: "I've been bursting to tell u all!!!! .. I will be taking part in @BBCOne NEW exciting gymnastics show #Tumble eekkkk!!!"
Sarah Harding and Lucy Mecklenburgh
After splitting from her fiancé Mario Falcone, Lucy has become a fitness queen and now runs her own company, Results With Lucy.
But she also admitted to feeling the nerves, saying: "I'm scared, nervous and more excited than I can describe about Tumble! To have the opportunity to learn a new skill is a dream come true for me. Although I'm sure I'll be falling over a lot before then!"
It's not the first reality show Lucy has been linked to since leaving the Essex-based show, as in December she was been hotly tipped to join Celebrity Big Brother, alongside her co-star Sam Faiers.
THE SECRETS OUT ....— Lucy Mecklenburgh (@lucy_meck) June 13, 2014
Girls Aloud singer Sarah Harding will also be joining Lucy on the Saturday night show and said: "I'm really excited but a bit nervous about what it is going to be like doing Tumble! I'm really looking forward, but also a little bit scared, about all the training I'll be doing ... but at least it beats going to the gym!"
Rounding out the host of celebs are Ian 'H' Watkins from Steps, fitness legend Mr Motivator, Loose Women's Andrea McLean, Sugababe Amelle Berrabah, boxing champion Carl Froch, Eastenders actor John Partride, actor Bobby Lockwood, and Dynasty star Emma Samms.
Joining Louis on the judging panel are former Olympian Nadia Comaneci, Commonwealth Games champ and sports broadcaster Craig Heap and cirque artist Sebastian Stella.