How to lose weight and keep it off

With so many fads, advertisements and 'bikini model' programs out there to confuse the poor consumer, what is the best way to lose weight and permanently keep it off?

Zumba? F45? CrossFit? BodyPump? Endless cardio? What about Lean cuisine? Eating clean? Cleanse diets???

One of these is the magic bullet, right? Surely so…

Well, yes, and big, glorious NO. Before we discuss the truth behind weight loss, we must first understand the simple principles behind the human metabolism and energy balance – the simple version:

1. Food is consumed by the body.

For each macronutrient molecule (carbohydrate, protein or fat), a set number of calories (unit of energy) is harvested (note that alcohol can also be used for energy, in fact, it’s the number 1 priority fuel source) for the body to do what it needs to do on a daily basis; move, think, breathe, exercise, etc. The number of calories (approximate conversion to kilojoules kJ is x 4) is approximately as follows:

  • 4 calories (or 16 kJ) per gram of carbohydrate and protein
  • 9 calories (or 36 kJ) per gram of fat
  • 7 calories (or 28kJ) per gram of alcohol

So, over the course of the day, your body will have consumed a certain number of calories, i.e., a certain amount of energy, e.g. 2400 calories (or approx. 9600 kJ).

Please note that on top of this discussion is the importance of micronutrients (vitamins and minerals), though for basic understanding of losing weight, they’re not particularly relevant.

2. Basal Metabolic Rate (BMR).

This is the amount of energy your body needs on a daily basis, taking into account basic bodily functions, when at rest (not including physical activity!). Now this value is usually semi-constant, but a bit of a red-herring in terms of weight loss, as an individual’s activity levels differ wildly from person to person, making the actual number unhelpful. The common methods for energy production are discussed below.

3. Activity.

Doing any form of activity beyond simply lying down flat at rest will require energy. Primarily, this comes in the form of glucose (a simple sugar), derived from both blood stores and glycogen (a stored form of glucose in your cells) through a process called the Krebs Cycle. Secondary to this is the process of using fat, in the form of free fatty acids (released from adipose tissue as triglycerides) through the process of Beta Oxidation*. 

*It is important to note that both these forms of energy production occur simultaneously within the body.

So, when you combine a rough estimate of your activity level and you BMR, you get an (albeit extremely rough due to wild variability when measuring on a molecular level) estimation of the amount of energy your body uses throughout the day.

4. Calories in vs. Calories out.

 That is; the key to losing weight is to expend more energy than you take in; exist in a calorie deficit. Thereby requiring the body to harvest energy from its fuel stores (adipose tissue – ‘fat’).

Some of you may have heard this before.

It is (basically) that simple. There are hormonal, micronutrient and genetic factors that may play a role in clouding this simplistic view, but don’t fall into the trap of this being the reason why you can’t lose, or struggle to keep off, weight.

The Long – Term Solution.

Now, the crux of the discussion.

Too many people, think the solution to creating this energy deficit is through starving yourself and doing endless hours of cardio. Will that work?

Yes. For a time.

See the problem with our bodies is that they don’t want to be thin and toned and ripped. The thin, toned and ripped guy or gal was the first to perish in a famine or when food was scarce. You know who lived? The fat guy. He lived a long old time, as when his body required more energy than he could scrounge together, he had these wonderful fat stores to call on.

Conversely, if the body detects that food intake is getting low (i.e. long term calorie- restricting diets), it will actually adjust to make the body more efficient, adjusting to get by on less, lest it waste away to nothing, ergo, bring weight loss to a screeching halt.

This is the single biggest problem amongst the demographic of women 18-50 trying to lose weight; under-eating.

So, what the hell do we do?!

The only sustainable, long term solution is to raise your BMR. How do we do this? I’m glad you asked…

Muscle is one of the most expensive tissues in the body, meaning that it uses a LOT of energy simply being there. If you are to add a kg here or there of muscle onto your frame, it will make a noticeable difference in your BMR. This is achieved through resistance training; building towards heavy (relative to you) resistance training in the gym or studio, to provide stimulus for your muscles to grow.

THIS is how we foster long term weight loss. If resistance training is coupled with an amount of moderate cardio and we take in a generous amount of food, slightly below our approximate expenditure (from good sources, with plenty of vegetables and protein of course), we can facilitate weight loss that will be long lasting and more permanent.

Oh, and before I go..



Zac Kelsey B. Ed, B. ExSS

Exercise and Sports Scientist & Injury Management Specialist

Zac has a wealth of experience in the exercise field, having worked in a variety of settings over the past decade. With a natural inclination towards injury management and pain relief through corrective exercise and the intricacies of high-end resistance training and power lifting, he has carved out a niche within the broader scientifically-based fitness community. Having successfully rehabbed hundreds of injuries and conditions over the past 3 years, Zac has particularly focused upon lower back, shoulder, hip and knee dysfunction. From his private studio in Kedron, QLD, he works with general population patients and athletes alike, both in injury management and high performance coaching/programming. Zac has worked as an educator to personal trainers and allied health professionals alike, having run workshops, professional development lectures and seminars on an individual, group and corporate level. He is a content creator for numerous institutions as he shares his methodical processes and observations when addressing particular issues and how these practices align with the latest scientific research for the education of other up and coming professionals. If you are interested in any further information about Zac’s services, he may be privately contacted via or on 0402468874.