'Commando' has some choice words for Michelle Bridges' post-birth fitness critics.

Image: Getty.

Michelle Bridges and Steve ‘Commando’ Willis welcomed their first child together, a little boy named Axel, last month.

Since it was first announced in early 2015, Bridges’ pregnancy consistently made headlines — primarily due to the fitness routine she pursued. As a professional trainer and Biggest Loser coach it shouldn’t have been surprising that the 45-year-old kept herself fit and active, but she faced constant criticism from her social media followers and experts for taking things too far.

This negativity has continued since Axel’s birth; just recently, Bridges was accused of sharing “irresponsible” post-natal fitness recommendations — namely 56 minutes of walking and jogging — on her Instagram account.

In public she’s appeared unfazed by it all, but according to her partner Steve ‘Commando’ Willis that’s not necessarily the case.

“It definitely had an effect on her, but she is a big girl and it will pass over time. It is something she has always done. She has always liked to get out and about, feel good in herself,” Willis told Nova hosts Fitzy and Wippa this morning.

“Also, psychologically it helps to calm her mind, as many people out there that exercise know.”

Watch: The 5 pregnancy symptoms nobody warns you about. (Post continues after video.)

Willis, a personal trainer himself, also took the opportunity to highlight that a sedentary lifestyle is more harmful that being physically active after childbirth.

“All these people that just get on her coattails to cut it down use it as leverage to voice their opinion. So be it, but the lounge chair and other things are killing people a lot more than someone who has just had a baby, pushing their pram out on a footpath,” the 39-year-old said.

“People pigeon hole. So now she’s a new mother with a baby, she can only speak to new mothers. Her audience is much bigger than that and we’ve got to be mindful of that.”

Throughout the headlines and public discourse Bridges has remained steadfastly silent, but in her first post-birth interview the 12 Week Body Transformation founder defended the way she’s approached exercise both before and after giving birth.

“A lot of people were freaked out that I was exercising [while pregnant]. But there is research as long as your arm on the benefits of exercising," she told the Australian Women's Weekly.

"Not everyone can exercise during pregnancy — I understand that — but if you have been given the all clearance by your specialist, there are some incredible benefits to you and the baby during pregnancy, the birth, after the birth and the future."

Bridges explained she had gained 14kg during her pregnancy, but was in no rush to lose the remaining weight. “I haven’t trained at all [since giving birth], I’ve just gone for walks. I am looking forward to getting back in to it," she added. (Post continues after gallery.)

As for the social media critics, Willis says he and Bridges are both determined to keep doing what they've always done.

“We can allow it to affect us and alter the way in which we do things, or we can stay true to ourselves. That’s what I believe the majority of people out there want us to do is to lead from the front, not just through what we say but our actions,” he told The Glow last month.

“I just feel sad and sorry for the people who feel there’s a need to be like that. Why do people have to cut other people down and have nasty things to say? It’s like, stand in front of a mirror — what’s going on in your life that makes you feel you need to have a go at others?”

Right on.

How did pregnancy affect the way you approached exercise?