The trainer has helped Rebel lose about 20kg over the year, with the 40-year-old actress now within only a few kilograms of her goal weight.
Speaking with Yahoo Lifestyle, Jono shared the "most important" part of Rebel's weight loss journey.
"I'd say her consistency has been the most important thing, if you're consistent and you're getting amazing results then it's just going to continue to show, even if it's not just in your appearance, but it's also going to help in bringing out the best in you," he said.
"We sometimes forget about what fitness and results actually does, it's not just about losing weight, it gives you so much more confidence."
Rather than attempting a 12-week challenge or something else short-term, Rebel understood it would take time to make real lifestyle changes and has focused on making her new diet and fitness program sustainable.
Jono also revealed his favourite tip that he shares with all of his clients, which is surprisingly simple.
"For reaching your fat loss goals, I'd probably say my favourite tip that I love to give out is: eat to be satisfied, not to be full. And that goes in terms of incorporating enough calories into your diet, because at the end of the day, we eat to be satisfied, we don't eat to be full or bloated.
"Because all that's going to create is that you're going to be tired, it's going to be hard to process, you're not going to absorb all the nutrients. So, I think when you know you're satisfied, stop there and then give it two hours and then eat again. Rather than just eating large meals where you're just going to feel tired."
This is especially important as we head into the festive season with the trainer adding: "I love people enjoying it, I think that's one of the key things on why people actually train with myself and Acero, because of our easy approach."
If you're hoping to stick to your fat loss goals over this period, Jono suggests working out how many calories you need every day, and then making changes based on events that come up at this time of year.
"It's calories in versus calories out. So, if you know that you're going to have a night out, you're going to go out with the team for Christmas drinks, dinner, lunch - whatever it is, you've got to play around with your calories.
"So, are you going to skip breakfast and then use those calories to consume for lunch and that's the thing about having a personal trainer, you can have personalised plans to help you reach your results."
Speaking about his involvement with the Alternative Meat Co, Jono said that if you're wanting to indulge a little bit, but also stick to your goals, you could try making switches from a meat option to a plant-based option.
"You could use the Alternative Meat Co sausages rather than using normal sausages that contain a lot more fat than the products that Alternative Meat Co have. For example as well, let's talk about white bread versus rye bread, I think it's more about choosing better options that are going to incorporate better macronutrients [carbs, fats and proteins] for results."
However, Jono isn't suggesting you need to be entirely plant-based if you don’t want to, it's all about balance.
"For myself, my philosophy would be more incorporating different styles of protein variations. So, if you're going to go for that approach, it might be adding tofu, adding plant-based dishes. I wouldn't go full plant-based personally, because you're so restricted to so many options, but for me I'd go more the approach of incorporating it all and all that balance.
"I'm all about balance, if you look at myself and Acero and the people that I work with, it's all about balance."
"When you think about a diet, you don't want it to be so restricted, because at the end of the day, you're going to give up on it. For me, the flexibility has allowed my clients to get results and that's what I've focused on 100 per cent."
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