She accompanied her post with pictures – one taken a month after her baby boy was born, the second a year later and the third recently.
‘I wish I had a few from in between the first and second so you could really see how slow my progress was but alas...I was busy covering it all up those months, not posing in my unders!’ Katherine wrote.
‘Anyway, I have a beach vacation coming up, a new job I start filming in April and my deep desire to feel fit, strong and sexy propelling me forward the last two months to finally loose the last of my baby weight and do a deep dive search for the ab muscles I knew were buried under that belly somewhere!’
Katherine went on to explain that she had been inspired by the before and after pictures shared by another mum Rach Parcell, who took part in the ‘bbg’ challenge – created by Australian fitness star Kayla Itsines to get back in shape after the birth of her baby.
‘I had never heard of it [the challenge] but she looked so damn great (she had her baby just a few months before me) that I had to check it out,’ Katherine explained, adding that she had then downloaded Kayla’s app Sweat.
‘[It] features several different #bbg programs you can choose from and makes it incredibly easy to do anywhere, which for me means in my bedroom at home!’ Katherine revealed.
Kayla's 'bbg' challenge - also known as her 'Bikini Body Guide' - is a 12-week workout schedule which has built up something of a cult following since it's conception.
On her website, Kayla describes the 'basic format' as being easy for people to get started on right away.
'The program begins with smaller challenges, then ramps you up over the following weeks, to higher levels,' Kayla explains.
'This allows your body to continue adapting, and helps to avoid plateau. A glossary of each exercise is also included to ensure you have the best direction for form, and technique.'
‘I won’t lie, the workouts are real ass kickers but the progress I’ve made in only 5 short weeks has kept me motivated and inspired to keep going!' Katherine wrote about her own experience.
‘I am so grateful I’ve had a full year to find those ab muscles and get my butt back up where it belongs and wasn’t forced by work to snap back into shape but it is time to make the strength, fitness and overall health of my body a priority and I am so grateful that @rachparcell shared her story and got this mama motivated!' she concluded.