The Hackney rapper accompanied Millie on her trip to the gym yesterday (30 July) and even captured some of her moves on video to show his fans.
Clearly Pro Green was proud of his future wife's efforts, as he uploaded one snap of her lifting a heavy bar while in a sit-up position and wrote: "Go on bird! That's what we like to see! @camillamackintosh"
He then added a short Instagram video clip of Millie and her personal trainer and tweeted: "Definitely gonna be in trouble later. Hats off though she's properly dedicated x"
The Made In Chelsea star was seen kitted out in a white camisole vest, a pink sports bra and black shorts. She also wore a cool pair of trainers with pink detailing and tied her hair into a messy bun.
However, it doesn't look like Millie was too pleased with her fiancé's filming, as she turned around to give him the middle finger on more than one occasion. Oops!
Millie, 23, has embarked on a strict exercise regime this year in a bid to get rid of her "wobbly bits" for her upcoming nuptials.
She also recently admitted to struggling with insecurities about her looks when she was younger and even revealed that she became so conscious of her teenage acne that going to school was unbearable.
"I was skinny, had glasses, wore braces to realign my jaw, had full-on yellow hair after a home dye job and really bad acne all over my forehead," she said.
Well, she's definitely looking fit and glowing these days - even in the gym!
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