Chasing My Ideal Weight: Part 2


The previous post (which you can find here) provided a bit of history behind my aim to maintain a goal weight. Ultimately, I want to feel happy with the way I look, and be confident in myself. I get hung up on whether or not my own “love handles” are feeling extra squidgy or not. And that’s OK. Everyone is entitled to their own opinion about their own body. What doesn’t matter is other peoples’ opinions about your body. They aren’t as intimately familiar with you, the workings of your mind, or what you hold as an ideal body image for yourself. But if you aren’t happy, set some goals, and try to make a change.

My own change is underway as part of the new year. Last post I mentioned BMI, and some specific weight numbers, and to me those are relevant. To other people they might mean nothing. It really depends how you want to approach weight loss. Sometimes people just want to clean up their eating habits, start exercising and stick with that until they visibly notice a change in their body shape. I personally have more of an affinity for numbers, and being able to measure things out. And that is something that is easy to apply to weight loss, and not only provides a way to measure it, but a method to achieve it as well. It does, however require a bit of research (aka Googling).

Regardless of which method appeals to you, there is one “rule” of weight loss in my eyes: the basics are the best. The hugely successful weight loss companies such as Jenny Craig or Weight Watchers simply utilize the basics, and they do extremely well in simplifying it, and selling it as their own. But if they are just using the basics, why can’t you use them yourself?

Some of what I write as a part of this blog series will involve a bit of numbers, but I will strive to make them as friendly as possible, and break down why they are important as I go. There is also a couple of basic concepts to understand.

Firstly, the concept of energy balance. Your body is a machine. Every day you get out of bed and move around a bit until you get ‘stuff’ done. Simple, right? Well, all the moving you do requires energy, the more moving you do, the more energy you use. In fact, even if you were to lay still in bed, and stare at the ceiling all day, simply being alive would use up energy. Something has to power your heart beating, your muscles to help you breathe, and even power your brain to think. If you are really active (running, swimming, going to the gym, etc.) then you require a lot more energy for all the additional moving. This is your energy output. But all that energy has to come from somewhere. For the most part, that energy comes from your food. This is your energy input. To maintain a given weight, your energy output must equal your energy input. To lose weight, your energy output must exceed your energy input. And if your energy output is significantly less than your energy input, then all the extra energy you take in gets stored. And yes, it stores itself as fat.

All food has an energy content based on the nutritional components which make that food. I am going to refer to this energy in kilocalories (more commonly called calories (cal)), as I am more familiar with caloric values, despite kilojoules (kJ) being more common in Australia. Ultimately food labels often have both cal and kJ on there. But if you want to follow along in kJ instead of cal, or you are reading a food label that doesn’t have cal, there is a conversion:

1 calorie = 4.18 kilojoules            OR          1 kilojoule = 0.239 calories

Food labels tell you the energy per serve of food, and the energy per 100g of the food. Therefore, if you stick to the suggested serves, or pretty close to it, you can estimate how many calories you are consuming. For example, my bread packaging says that 2 slices is a single serve, and it contains 148 calories (round it off to 150 to keep it easy). But what does that 150 calories mean? How do I know how much I can have? Do I have to run for 12 hours to burn the equivalent energy to those bread slices? To answer that, you need to understand the second concept, which I will call Passive Energy Burning.

Passive energy burning is what the body does to keep itself alive. You don’t tell your heart to beat, your chest to expand to breathe, or your eyes to blink. It just happens, and it uses energy. This is commonly called your basal metabolic rate (BMR), it is the minimum energy required to keep your body functioning in its current state. There are equations that can be used to estimate this:

For men: BMR = 88.362 + (13.397 x weight in kg) + (4.799 x height in cm) – (5.677 x age in years)

For women: BMR = 447.593 + (9.247 x weight in kg) + (3.098 x height in cm) – (4.330 x age in years)

The result is in calories. This passive energy burning from your BMR, is then multiplied by an activity factor that represents your average daily activity levels to get to an overall energy output:

Little to no exercise Daily kilocalories needed = BMR x 1.2
Light exercise (1–3 days per week) Daily kilocalories needed = BMR x 1.375
Moderate exercise (3–5 days per week) Daily kilocalories needed = BMR x 1.55
Heavy exercise (6–7 days per week) Daily kilocalories needed = BMR x 1.725
Very heavy exercise (twice per day, extra heavy workouts) Daily kilocalories needed = BMR x 1.9

 

Try and work this out for yourself. What you come up with is your recommended daily caloric intake. For me, at present, I weigh 84kg, I am 177cm tall, and I am close to 27 years old. That gives me 1910 calories from the first equation. I also do moderate exercise 3 – 5 days per week (or vigorous exercise on 3 days per week, but let’s be conservative and simple), so my activity factor is 1.55. This means the energy requirement for me to maintain my weight is 2960 calories per day. Important note: this equation is not 100% accurate, so I generally shave 10% off of this before I do anything else (i.e. it comes down to 2664). So I will keep it simple and say my energy output to maintain my current weight is 2700 calories per day.

Bringing this back to energy balance now, if I need 2700 calories to maintain my weight, I want my energy input to be less than that to lose weight. In fact, if I was targeting a loss of 1kg per week, I would need my daily energy input to be 1100 calories LESS than my maintenance requirement. I would need to consume 1600 calories per day. And that is what I will strive to do.

Hopefully that makes sense, I have explained the 2 key things for weight loss, energy input and energy output, and I have highlighted a method to quantify both. As I write this, I realise it is creeping up in length. But this is the underlying theory behind weight loss. It is not overly complicated, but if you are not familiar with it, you might need to read things a couple of times to grasp it. This forms the foundation of how I plan to drop a few kilograms. And in future posts I will put it in action, and provide the tools I use along the way.

Thank you so much for reading to the end, I am glad I have been able to share this with you.

Cheers,

Matt

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