Strictly judge Shirley Ballas shows off her 'fit body' in a chilly 3-degree Celsius bath as she prepares for the upcoming season.

STRICTLY Come Dancing’s Shirley Ballas showed off her killer figure in a bright yellow swimsuit as she went for a dip in a plunge pool.

The BBC competition’s head judge shared a video to her Instagram of jumping into the ice cold bath in her back garden.

Explaining she had been working hard to get back into a pair of trousers she had when she was 20 before the first night of Strictly, she had gone the extra mile with the chilly health fad.

a woman in a yellow bikini sits in a pool of water

Shirley prepared her body for the first night of Strictly live shows with a plunge pool

a woman in a yellow tank top is swimming in a pool

The star made no secret of the chill as she filmed herself bathing

a woman holding a paddle with the number 10 on it

The star is the glamorous leader of the judges panel

Teetering on the edge of the pool, Shirley told cameras: “So this morning now is the first day of Strictly.

“I’ve done my exercise. I’m about to go my plunge pool, but I’ll be posting to – remember those trousers that were too tight? I’ll be posting them today, and the results, which I promised myself by the time I did the show would be much better.”

“Anyway, in for a dip!” she declared, before sliding into the water, gasping at the cold temperature, telling fans it was “freezing” and she needed to focus on her breathing.

“I started at six degrees. I went to four degrees, and today I’m at three degrees,” she said. So I’m getting colder and colder and colder.

“Strength in the mind.”

It seems her efforts with her health and wellness have done the trick, and later on she revealed she had succeeded in her trousers target ahead of the first night of Strictly tonight.

The series, now celebrating its 20th year, will see Shirley reunite with Craig Revel-Horwood, Motsi Mabuse and Anton Du Beke to give their scores and feedback to this year’s celebrities.

There will be no eliminations this week, with the stars putting their best foot forward in order to impress the judges.

The scores they dish out will then be rolled over to next week, with those combined with the public vote deciding who will landed in the dreaded first dance-off.

The series is under particular pressure this year after being faced with a sea of scandals that resulted in two professional dancers – Giovanni Pernice and Graziano Di Prima – being axed from the show.

With the investigation into their rehearsal room conduct still ongoing, Shirley declared at the beginning of this month that “nothing will dampen” the spirit of the beloved show.

Speaking about the situation, head judge Shriley said: “To be perfectly honest, I stay in my lane. I don’t condone anything that some people may have gone through, but all I could say is the show that we will be producing this year is full of humour.

“I’ve never laughed so much in all my life from the launch show. I mean that Chris McCausland and Wynne Evans, they’ve got their own little battle going on. I think it’s just such great camaraderie … this year and everybody seems bright and light, and nothing is going to dampen this show in any shape or form.”

She continued to PA:”It’s got new twists and turns this year, and don’t forget the millions and millions and millions and millions and millions and millions of people that this show brings joy to, from every age group – from four all the way up to grandpa or grandma.”

She added her hopes that the show will be “absolutely joyous”

Strictly Come Dancing kicks off tonight at 7pm on BBC One.