Conveniently, it’s near my office, so I went for a consultation. The trainers there talked me through exactly what happens and how it works. They offer the full package; workouts and nutrition as well as constant support.

I started doing two workouts a week after work on a Tuesday and Thursday, with my new personal trainer, Richard. Each session would last about an hour and we’d do a mixture of upper body and lower body resistance training. We did a little bit of cardio on the bikes and pulled the sled but it was 95% resistance training.

I’ve always done cardio and I’ve always been pretty fit. I even did a marathon a few years ago – but I’d never really done any resistance training. Even my doctor recommended I try resistance training because I take hormone replacement therapy (HRT) and honestly, the results have been just amazing.

I also started tracking the food I was eating on the gym’s app which calculates your macronutrients. I worked really closely with Richard to make sure I was consuming the right amount of calories during the week. He was there for me constantly, 24/7. I could message him now and he’d answer me while he’s on holiday.

I realised that the balance of macros in my diet were completely wrong. I wasn’t eating over my daily calorie limit, but the combination of macros was really out. I was eating 70% carbs, very little protein and very little fats. Changing my nutrition was a real eye opener; it made a massive difference.

My plan was to eat more protein and fat, which would support my muscles and help me to burn more fat. Plus, protein would keep me fuller and stop me reaching for more carbs.

I made some simple carb swaps; instead of potatoes, I have couscous; instead of a banana I have some berries. I didn’t realise a banana had so many carbs in it. Instead of crisps or chocolate after I’ve had my dinner in the evening when I’m watching TV, I have two squares of dark chocolate and it’s enough to satisfy me.

The main problem I always had pre-transformation was weekends. On Fridays I’d be like, “okay, how many glasses of wine can I have?” My partner and I would get a takeaway and I would eat quite a lot.

During my transformation however, I was much more careful about the amount of carbs that I ate, and the amount of wine I drank.

I was just really conscious of what I was doing on the weekends because I didn’t want to screw up what I’d done during the week. I had to focus on it 100% because if you are prepared to commit, then you cannot fail.

Every fortnight, my trainer would check my measurements and take photos. It was so helpful to see progress; without the photos I wouldn’t have realised I was doing as well as I was.

I finished my transformation in mid-April; it took 24 weeks. In that time, I went from 39% body fat to 16%; even I think that’s insane. I weighed 65.7kg when I started in October and I’m now 55kg at 1.67m (5ft 5in); so I lost almost 11kg.

My partner, who is very fit, also ended up losing 8kg simply because he was eating the same food as me. We go to the gym together now too which is nice.

And, at the end of January, I started to see abs, which I didn’t think I would ever see on my body. Resistance training had just completely changed my body shape and my strength.

Over the Christmas period, I just ate normally. I had a few glasses of wine. I just thought, you know, I’m going to enjoy it. My trainer told me not to track calories on Christmas Day or Boxing Day. You’ve got to be able to live, otherwise it would be ridiculous.

Although the 24-week transformation is finished, I still see my personal trainer once a week. Then I do three of my own sessions because now I know what I’m doing as Richard has shown me.

I still track what I’m eating just for my own benefit, so I know what I’m doing. And my weight hasn’t changed since I did my transformation, and I’ve been on holiday to Sicily eating lots of pasta and drinking lots of wine.

I also make sure that I do at least 10,000 steps a day because that is key. When I was doing my transformation, I upped it to 15,000 a day, but now I just make sure I’m over 10,000.

My family has been massively supportive. My two 20-year-old twin daughters are at university, so they were away for quite a bit of the time but they were very impressed at the rate my body was changing. They kept looking at my pictures and saying, “Oh my gosh, you’re shrinking!”

I’ve knocked quite a lot of time off my 5km Park Run too. I was taking more than 29 minutes before and now I can do it in 27 minutes. My aim is to get it down to 26 minutes.

Strength has really helped with my running and other cardio; I have a lot more energy and I can run a lot faster for longer. I’ve got so much more left in the tank now.

My next goal is to build upper body strength. I’m really working on getting some definition in my arms and to keep looking as fit and as toned as I can, as I get older.

I’m lengthening the quality of my life is how I see it, really. I feel much fitter, much healthier and mentally better. I feel like if I can achieve what I did, then I can achieve anything.

Sheila’s top tips for losing weight in the menopause

As told to Lucy Gornall