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Calories in Vs Calories out: Is It Really That Simple?

Devon is a CPT and Nutritionist who assists individuals in achieving their goals by employing a balance between mental & physical kinship.

Let's try make sense of all of this

If you’ve spent any deal of time looking for ways in which to change your physique you’ve more than likely come across the timeless equation: calories in vs calories out. Specifically, this refers to the energy yield (in calories) from food and drink that we consume on a daily basis and the energy we expend due to exercise, day-to-day tasks, and our resting metabolic rate. In theory, if we eat more than we expend within a specific time frame we will gain weight. And if we spend more than we consume we lose weight. And of course, if we consume the same number of calories, we burn then our weight will remain unchanged. This all sounds simple but the reality is people know this is not the only factor that affects our weight loss/gain/maintenance goals. If it were so, why do we see so much fuss over low vs high glycemic index carbohydrates? Why does it matter whether you eat before bed or not? Why does portion size matter if you’re still getting in the calories you require? And why is macronutrient breakdown so important? These questions, amongst others, lead me to do some research on the subject to find out what some of the most important factors are that we should consider when trying to improve our physical well-being and how we should be applying them to get the most out of what we put into our bodies.

Let’s break it down real quick

To best understand what causes us to gain and lose weight it helps to instead refer to “weight” as either fat or muscle. As much as the body loves to maintain homeostasis, it is in constant fluctuation in an effort to do so, and the things we put into our mouths affect this never-ending cycle. At any given time, we are either in an anabolic (building up) or catabolic (breaking down) state. These building up and breaking down states can affect both muscle mass and fat. Bearing this in mind we can move on to the factors that affect these different states.

The burning question

Is “calories in vs calories out” a reliable indicator for assuming weight loss and weight gain? The short answer is yes. If you consistently ingest more energy than you spend, your body will store those extra calories as fat or muscle and you will subsequently gain weight. Conversely, if you do not eat or drink enough calories over time your body will use stored energy reserves and you will ultimately lose weight. However, the body quickly adapts to change and will slow down the rate at which you both lose and gain weight in an effort to keep balance. As you gain weight, energy requirements increase and more energy is needed to gain weight at the same rate. Just as energy requirements decrease as weight decreases and the body goes into survival mode trying to hold on to as much weight as it can. Various other factors like exercise will come into play and have an influence on how these calories are used in the body. For example, if an individual consumes an excess of calories but performs strength training, the extra calories provided will first be used to repair and grow the muscles trained before the body stores them as fat. Typically, an extra 300-500 calories a day above maintenance is required to assist in gaining lean muscle mass. Any more than that and there is the potential for fat gain. To lose fat, an individual should aim to consume 300-500 calories less than what they require for maintenance daily to put the body in a calorie deficit. Any more than this amount and the body may think it is starving and will break down muscle tissue to provide it with the energy it needs. Healthy muscle gain and healthy fat loss are achieved through making small changes and applying them consistently over time.

Can I have my cake and eat it?

The next conflicting issue that is often debated is that of the glycemic index (GI) of carbohydrates and how they can bring the fat-burning process to a halt. All carbs have a GI and this refers to the rise in blood sugar levels and the subsequent release of insulin to control blood sugar levels after the carb is ingested. Insulin is a powerful hormone that plays a vital role in the metabolism of protein, carbs, and fats, and shuttles nutrients into various cells around the body. The higher the GI of carb, the higher the surge in blood sugar levels and the more insulin that is released to bring levels back down to normal. This insulin spike will quickly deliver nutrients to muscles, the liver, and fat cells but it will also force the body to stop using fat as a fuel source. In addition, it will also store excess carbohydrates as fat once muscle and liver cells have been filled. So if insulin has the ability to store extra fat right after a meal, does “calories in vs calories” out still matter? Again the answer is yes. Ideally, you want to be eating the number of calories you need but you also want to avoid these insulin spikes for various reasons.

  1. Keeping blood sugar and insulin levels stable throughout the day will allow you to experience sustained energy and avoid crashes.
  2. Although you could be in a calorie deficit, you may not be burning fat as efficiently because constant spikes in insulin forces the body to change from using stored fat as a fuel source to using stored carbohydrates as a fuel source instead.
  3. High insulin levels have been linked to obesity, heart disease, and even some cancers.
  4. Over time cells become resistant to the effects of the hormone and this can lead to type 2 diabetes.

If you’re going to consume carbohydrates while attempting to lose fat, stick to whole grain, low GI sources like oats, legumes, peas, sweet potato, brown rice, and starchy vegetables. Keeping blood sugar and insulin levels low in conjunction with a calorie-restricted diet will ensure your body is burning fat round the clock.

Grilled or fried?

Next, we can move on to the quality of the calories we consume. What does this mean exactly? Well, it can refer to a number of things. How is the food prepared? Does it have any additives? What is the macronutrient profile, ie what percentage of its calories are from carbs, protein, and fat? These small considerations can largely affect how our body absorbs and digests these foods, ultimately determining whether they assist our lean mass gains or hinder our fat loss efforts. You see, although a slice of cheesecake and a lean steak may yield the same number of calories, the steak will more than likely contain more protein. And the cheesecake will certainly provide more carbs. So it is important to keep your goals in mind when choosing foods and opt for the options that will provide nourishment for the body. Try to stick to foods that are in their most natural state as possible. Canned foods, baked goods, and other processed items typically do not digest well and don’t provide much nutritional value.

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All or nothing

For many years my approach to nutrition was not the healthiest, and through my years in the bodybuilding industry I have come to learn that many competitive athletes adopt the same approach; an all or nothing approach not a healthy one, and I’ll explain why). During ‘off season’ athletes and seasoned gym rats alike tend to eat a fairly balanced healthy diet most often meeting their macros and consuming sufficient calories for maintenance or growth. But when it comes to dieting, and I’m talking serious dieting to get competition or photoshoot lean, all may start well, but over time as the body realizes it’s taking in far fewer calories than it should whilst you’re pushing harder than usual at the gym, you may become prone to developing an obsessive compulsion with food, constantly thinking about your next bland meal and worse of all being hungry almost all the time.

It's not unusual to see post competitors head out to their favorite pizza joint or burger bar and indulge as a reward for their hard work and discipline, but far too often this can start to form a habit. As I’ve seen with myself and many others this binge tends to go on for days if not weeks and in a short space of time one can find themselves back at square one or even worse off.

It took me just a few weeks to go from 85kg to 101kg. One can only imagine the mental anguish, frustration, and disappointment after seeing their physique go from township dog shredded to what was technically classified as obese. And as I mentioned this is just all too common in this industry.

Armed with a degree in clinical psychology, two certified personal training qualifications, and being a nutritionist, I decided to do some research as to why so many of us are prone to relapsing after a successful diet. For competitive athletes it may be a tad more difficult to regain control after being so lean; the body and mind are constantly fighting to maintain homeostasis and all it wants to do is feed after a long diet.

But I have found that the best method of retaining as much of a lean physique as possible after dieting is to simply ease your way slowly into eating the ‘normal’ meals you did before you started dieting.

Keep in mind these important factors:

  • Your body’s metabolism is at an all-time low and is thus not expending as much energy as it did before you started dieting
  • Therefore, a slow and steady increase in calories each week will allow your energy expenditure to gradually return to where it likes to be
  • Go out and spoil yourself with a satisfying treat, but in moderation. One cheat meal a week should not affect weight gain significantly
  • Continue training and train hard. You now have extra energy coming in and your gym sessions shouldn’t feel like a chore anymore
  • Monitor your weight. Weigh yourself once a week at the same time first thing in the morning and if you notice you’re picking up weight too fast (<.5kg a week), cut back on some of the food you’re consuming or increase your daily caloric expenditure by means of extra cardio or simply moving about more than usual
  • Take weekly progress pics to see how your body is changing over time.

Hopefully, these tips help prevent you from landing in the position I found myself in too many a time.

Keep an eye on how much you’re eating, track your training intensity and volume, and don’t forget to record how your body responds over time.

Until next time, keep grinding!


Apple or donut

Apple or donut

© 2021 Devon Bruce

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