Image: iStock.

I know so many women (and men) who have injuries they can’t shake and that are the result of personal trainers under pressure from their gym to get weight loss results, Biggest Loser-style. They’re usually guys who have done an eight week course and middle-aged women who have never lifted a weight before and are particularly prone to injury and slow to recover.

One of the worst stories I ever heard though was from a woman named Micaela Middleton. She’d just had a baby and thought it would be nice to meet up with other mums for a bit of gentle exercise, so when she saw an ad for a trainer who claimed to specialise in mums and bubs, she signed up.

RELATED: Everything you need to know about exercising after a C-section.

She turned up for the first session to find a burly young guy laying out medicine balls, boxing gloves and heavy dumbells. Nervously, Micaela pointed out that her baby was just four weeks old, she was breast-feeding, and she’d also had spinal surgery. The trainer assured her he knew what he was doing — then proceeded to get Micaela performing sprints, burpees, high-knee runs and sit ups with a four-kg medicine ball. When she ventured her body might not be quite ready for that, he recommended star jumps instead. (Post continues after gallery.)

Fast, high-intensity exercises

Burpees

Skipping

Running up stairs

Star jumps

Mountain climbers

In retrospect, Micaela told me, she can’t believe she even went back. However, with so much media pressure on new mums to snap back into shape and a trainer who made her feel she should be fitter than she was, she was worried about looking like a bludger. Five weeks later, suffering bleeding and incontinence issues she went to see a health professional who ordered her to stop training immediately.

“Luckily any potential problems were rectified very quickly,” Micaela told me, but it still makes her angry that a trainer was able to present himself as an expert in an area when he clearly wasn’t.

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I’ve since discovered that trainers can do no more than a one half-day course which allows them to claim they are an expert in older women, new mums or any other speciality.

I’ve got nothing against trainers. Research shows that the best ones can help us get better results out of every workout, offer support and encouragement, make sure we use the right technique for our particular body and alignment, and guide us towards a healthier lifestyle in general with advice on food and recovery.

But how do you find a good one? I asked around for the best advice.

Tips for picking a PT

Victorias Secret Angel Adriana Lima with her personal trainer

1. You can't beat word of mouth. Ask friends, family or health professionals for recommendations.

2. Watch PTs and their clients in action at your local park or beach.

3. If you're a gym member and enjoy training there, ask for details of the trainers they have on staff. They should have different levels of qualifications and also be able to tell you about their background.

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4. Remember that you can always see an exercise physiologist who specialises in strength and conditioning instead. If you have private health insurance, that often works out cheaper as you'll get a rebate. If you have a chronic condition such as Diabetes or are recovering from serious injury, talk to your doctor as you're entitled to five free sessions on Medicare.

5. If you want to do serious strength training go to a qualified powerlifting trainer or Olympic lifting trainer. Don't just watch other people to see how they lift as your anatomical needs may be different to theirs. (Post continues after gallery.)

How the rich and famous stay fit

Lena Dunham.

Girls star Lena Dunham says exercise is vital to her mental health.

Margot Robbie.

Miranda Kerr.

Miranda Kerr weights for nobody. (Instagram)

Rosie Huntington-Whiteley.

Anna Kendrick.

Gisele Bundchen.

Bar Rafaeli.

Kendall Jenner.

Lea Michele.

Karlie Kloss.

Paris Hilton

Julianne Hough.

Beyonce.

Questions to ask

1. Qualifications?

They should have a minimum Cert IV in Fitness but I, personally, would want more than that. I want to know about their personal journey as well — are they just the occasional gym-goer who got made redundant and needed to fill in their time or have they been involved in sport and coaching their whole lives? Do they have a background in exercise science or exercise physiology?

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If they've taken additional courses, ask for details. A half-day seminar on training woman doesn't make them an expert in everything from mums to menopause. If they're teaching a skill such as boxing, check their expertise. Boxing is one of the best workouts possible if taught correctly but will fast track you to to injury if not.

Don't hesitate to ask questions

2. Length of time in business?<