"I always feel so much better after a workout," 38-year-old Melanie Luu says.

Melanie is 32 weeks pregnant at the time of our chat. She's been exercising at boutique gym, Sassi Fit, in inner-city Melbourne for several years, including throughout her pregnancy.

But training during pregnancy and after giving birth can be difficult to navigate.

Some personal trainers and instructors don't modify exercises or their classes for perinatal people as they would for someone recovering from injury.

Some new parents may be unaware of particular movements to avoid, held back by morning sickness or fatigue, or daunted by the prospect of injuring themselves.

Cultural expectations about losing weight after giving birth, led by a plethora of "fitspo" Instagram content, can also encourage some mothers to fixate on "getting their pre-baby bodies back" as soon as possible.

Rosie Purdue is a physiotherapist who specialises in pelvic floor and continence physiotherapy.

She has more than a decade of experience and is the founder of Hatched House, which provides allied health services for women.

Rosie says that it's not surprising how delicate the return to exercise after giving birth can be, given the myriad of changes that happen to the body.

"During pregnancy, the mother's weight and posture changes, and there is a significant stretch of the abdominal and pelvic floor muscles."

Rosie says that after giving birth, "internally the placenta organ detaches from the uterus. This wound takes a minimum of 4-6 weeks to heal, regardless of how the baby is born [i.e. via caesarean or vaginally]."

Exercise encouraged during pregnancy

However, it's partly for these reasons that maintaining exercise during pregnancy and beyond can be very beneficial for the parent's health.

For those with uncomplicated pregnancies, exercise is actually encouraged. Among its many advantages, exercise can improve mood, sleep, sense of well-being and, of course, fitness levels.

Exercise during pregnancy has additional benefits including a decreased risk of developing gestational diabetes, hypertension, and pre-eclampsia.

It's why the World Health Organisation recommends those with uncomplicated pregnancies participate in at least 150 minutes of moderate intensity aerobic exercise per week.

A recent University of Wollongong study surveyed nearly 700 women on their attitudes and beliefs around exercise during pregnancy.

While most believed that "regular exercise during pregnancy is safe" for themselves and their baby (94 per cent), many reported receiving "no or little advice from their healthcare provider".

This meant that they were unaware of or not meeting the World Health Organisation recommendations about exercising during pregnancy.

Melanie agrees.

"As a first-time mum, I've enjoyed modified exercises during my pregnancy and have learnt what is safe for me," she says.

While Melanie finds the idea of returning to exercise after giving birth "a little bit daunting", she's aware that she can, and should, ease back into it.

She finds the social aspect of group classes help keep her motivated.

Adapting and modifying workouts key to pregnancy fitness

Melanie's trainer, Caroline Molloy, owned Sassi Fit for seven years.

Caroline aims to help women achieve their health and fitness goals in a non-judgemental environment, specialising in pre- and post-natal exercise.

She was inspired to pivot from her career as a teacher to start the business after having her own troubling experiences when exercising while pregnant and after giving birth.

"There was a big lack of understanding on the pressure that has already been on the pelvic floor," Caroline explains.

For her, and many other new parents, this meant that trainers were prescribing exercises that added to that pressure. This had the potential to cause pain, discomfort, and even further damage.

"Some weren't really understanding what it felt like to have just had a baby and then be asked to do a burpee or jump around with weights."

Rosie notes that important modifications to exercise during pregnancy can include "making sure you can hold a conversation while you're working out and avoiding exercising on your back during the later stages [of pregnancy]."

Shrugging off the pressure and taking it slow

Unrealistic pressure to return to pre-pregnancy weight and appearance is also something that Caroline has seen encouraged by some gyms and studios and repeated by clients.

This can include encouraging impractical fitness goals too soon after giving birth, and body-shaming or framing anyone who doesn't achieve them as "lazy".

"They're often feeling that pressure of 'fitspo' stuff on Instagram," Caroline says.

"Things like 'I did this, and I've had five children – this is how I look, and you should be the same.'"

Caroline says it's understandable that being bombarded with these messages may mean some new parents need reminding that no two journeys back to exercise will look the same.

She recommends that perinatal people looking for a personal trainer, or even attending a gym class, ask if their trainers have qualifications in pre- and post-natal training.

"Even fitness instructors, I think, should be qualified in that, particularly when they're running a group class," she says.

Rosie recommends new parents "take it slow and listen to your body."

"For the first six weeks try doing your pelvic floor exercises, stretching and building up to walk comfortably for 30 minutes," she explains.

"When your baby is around six weeks, get a check-up with a pelvic health physio. They can guide your strength and fitness program for the next six weeks, before returning to higher intensity exercise.

"If something doesn't feel right, then get professional help."

ABC Sport is partnering with Siren Sport to elevate the coverage of Australian women in sport.

Danielle Croci is a policy officer and freelance writer and podcaster specialising in women's sport.