Not only was the bejeweled purple dress incredible, it showcased Amanda's ultra-toned limbs. Given that the star has been vocal about not loving exercise (she told Top Sante she's 'not a huge fan of exercise'), how does she get her legs so toned?
WATCH: Amanda Holden looks like a goddess for BGT live show
The answer lies with four super simple hacks – one of which you probably do every day anyway…
Amanda recently shared a video of herself hiking while on holiday, and according to fitness professional David Wiener, who works with fitness app Freeletics, walking is key when it comes to lithe limbs like Amanda's.
Amanda went hiking in California
"One of the most important (yet underrated) exercises to get toned legs is walking," confirms David. "Walking has so many different mental and physical health benefits and is incredibly important if you want toned legs.
"I always recommend that if you can walk somewhere, then walk! Swapping that 10-minute car journey for a 20-minute walk can truly be the difference in not only leading a healthier lifestyle, but helping get amazing toned legs."
Amanda Holden's legs are long and lean
Amanda has mentioned she's a fan of running before, saying that she goes for a run three times a week. "It's the one time I can be alone with my thoughts and clear my head," she said.
David agrees that running is a great way to achieve toned legs. "Regardless of your body shape and size, runners tend to have powerful legs as they are constantly working the large muscles of their body," says David.
Amanda regularly shares photos of herself atop a bicycle, enjoying bike rides with her family, and this is another activity her toned legs could be attributed to.
Amanda Holden loves a bike ride with her family
"Cycling is another great exercise which helps you tone your legs as you will be working your quadriceps when you pedal, which helps strengthen and tone your legs," explains David. "You will also be working the hamstrings and calf muscles, which gives you a true full leg workout."
4. Weight training
David does point out though, that as good as running, cycling and walking are, an element of weight training will really supercharge your journey to toned legs.
"Squats, lunges, deadlifts and box jumps are some of the best training exercises to help build toned legs," he says.
Amanda Holden regularly wows in leg-baring outfits
"The answer to toned legs is building muscle around the thigh, which is why incorporating cardio and strength training is vital," David adds.
We know what we’ll be doing in the gym this week…
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