Antony Costa took advantage of the 12 weeks before Christmas, opting to go on a fitness spree while the rest of us were tucking into mince pies.
The Blue singer, 39, looks completely different after the three-month-long challenge, having shed a whopping two stone.
Admitting he hoped to revamp his "dad bod," the former boy band star looked transformed after sticking to the challenge.
Antony took to Twitter to showcase his hard work, promoting the Muscle Food Weight Loss plan as he shared the story behind his new physique.
In the first photo, taken at the beginning of his challenge, Antony posed to the side, going shirtless.
The second snap showed him 12 weeks later, visibly slimmed down and toned after revamping his diet and fitness regime.
Thrilled with the results, the pop star wrote: "Happy New Year!
"OPERATION DAD BOD COMPLETE! 2 stone down in 12 weeks and I'm so proud of myself! All thanks to the Muscle Food Weight Loss Plan!"
In the comments below the post, Antony's fans praised his determination, impressed by his commitment to leading a healthy lifestyle.
One wrote: "Fair play Ant, top respect to anyone who goes out their way to improve themselves. Well done pal."
"Well done mate," added a second, and a third penned: "Inspired by this mate. I've got the same weight to lose!"
On Instagram, the pop star – who shares two young children with his fiancée Rosanna Jasmin – delved into the motivation behind his transformation.
Antony confessed he decided to overlook the lockdown and focus on getting fit, putting the plan into action when summer came to an end.
"A pandemic and a national lockdown wasn't going to stop me," he said.
"2 stone down in 12 weeks, I can't quite believe it! And it's all thanks to @mfgoalgettersuk.
"Honestly, with everything else going on, the one thing I wanted to focus on was my health. I've wanted to lose weight for a while and decided a few months back that it was time to take action so followed this plan!"
Antony admitted it was a struggle to focus on weight loss as an active dad, and thanked the weight loss plan for the spectacular results in a promotional message.
He said: "As a busy dad the last thing I really wanted to think about was having to prepare my meals and worrying about my calories.
"That's why the MuscleFood Weight Loss Plan has been such a lifesaver! I chose which meals and snacks I wanted for the week ahead and everything was delivered to me. Really couldn't be easier!"