But now it seems the 41 year old is more sporty than scary as she was spotted working up a sweat outdoors.
The singer was seen boxing with her personal trainer in sunny Sydney Park.
And clearly putting her all into the exercises, the former X Factor judge showed off her impressive physique in a pink and blue outfit.
Wearing a pink crop top, the mum of 3 revealed an amazing set of washboard abs.
And teaming the look with a tight pair of patterned leggings, the popstar flaunted her shapely legs as she ran across the grass.
Matching her outfit with her pink trainers, the Spice Up Your Life singer also sported a pair of sunglasses to shade her eyes.
With her dark hair tied up in a ponytail, the outspoken star seemed to be enjoying herself as she hit pads held up by her trainer.
At one point her long locks seemed to come loose, wrapping around her neck as she sprinted between boxing sets.
Stopping to pull her hair back from her face, the yummy mummy looked like she was in better shape than ever.
No doubt Mel is getting back in shape ahead of the Spice Girls reunion tour, which will be starting next year.
The singer will be joined by former bandmates Geri Horner and Emma Bunton, calling themselves GEM instead.
“In studio,oooooh @emmaleebunton,” shared Geri just last week on Instagram.
Mel is currently sunning herself in Sydney, taking to Instagram to share stunning shots of herself in front of the opera house.
“Sometime ya just gotta take a second, relax breath and appreciate #blessed (sic),” the songstress told her fans.
But despite the chill out time, the singer recently warned her 768,000 followers not to get on the wrong side of her.
Posting on her social media, the popstar shared a quote that she described as “setting her mood for the weekend”.
“I don’t have a short temper. I just have a quick reaction to bulls**t,” the photo read.
“Read this 3 times, take several seats,and then dress me #currentmood #settingthetonefortheweekend (Sic),” Mel captioned the image.