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The fundamental rule of fitness

Blue sky and a happy runner

There are a few questions that keep coming back to me as a trainer. How much should I eat? What should I eat? How much should I exercise and for how long? What’s best for me? What should I do? Thanks to the internet, we now have all the information we need at our finger tips. But I find this can lead us astray since there are soooooo many different opinions out there! You should do this, you should eat that BLA BLA BLA…Im not saying what you read is wrong, on the contrary, when it comes to fitness, a vast majority of the information out there is true. So how do you make sense of it?

When it comes to knowing how much to eat and how much to exercise, Im going to explain something inherently simple but that gets over looked more often than not. But first, let me say this: all trainers and fitness enthusiasts have there own unique style of training. Which means that their way of getting fit is going to be different. They do however, follow the rule I will explain in the next paragraph, they just show you their unique way of following it. Now up to you to find the path that best suits you!


The energy balance law

Energy is neither lost nor created. It simply changes form. In humans, its going to be from energy we eat to the energy we deploy to move around and carry out our everyday life.


The energy law and body composition

When we eat more energy than we use, our body will store all that energy, in the form of fat. When we eat less energy than we use, our body will use those fat stores to provide the required energy.

In very simple terms, eat more than you need and you will put on weight, eat less than you need and lose weight. This is the very fundamental rule of body composition. Since a vast majority of people I see and talk to online want to change their body composition, I believe this rule is important to remember.


Calories and energy

Ok so how do you figure out how much energy you need on a daily basis? As a start you can use this calculator . I do not encourage calorie counting as it gets very tedious and sucks the fun out of getting fit, but you need to have a general understand to how much calories you need. Wow hold up! Why do calories come into play here? A calorie is nothing more than a way to quantify energy. Without getting too technical, 1 calorie is the energy required to heat up 1 gram of water by 1 degree celsius, roughly 4.1 joule. So say you eat a medium banana, its roughly 105 calories. If you sit for an hour, you burn roughly 68 calories assuming you're around 150pds. And Boom that how it works, if you ate that banana and then sat for a whole hour watching tv, your would have 37 calories that your body would store as fat.


How to use this rule

What Im more interested in helping you with is HOW do you implement this rule into your lifestyle. There are so many ways to enjoy being fit without eliminating foods we love. What I really want you to think about is more about how much energy to do you require on a WEEKLY basis. The good news is that one cheat meal wont be bad for you, the same as one healthy salad wont make you shred weight instantly. Your fitness, body composition, whatever you want to focus on, is more a result of your ongoing habits rather than your daily doings. It’s ok to enjoy a dinner out with friends. It’s ok to eat chocolate cake with your kids. It’s ok to show up a party and say “Im going to out eat everyone here combined”…that ones more for me…The point is that your weekly energy balance is a better way to look at it than daily.


Energy balance and food

There are foods high in calories, mainly simple sugars like candy and other processed good and fats. The foods with less calories are the unprocessed foods, proteins and veggies. The less calories you eat, the less you have to exercise to balance out your energy. If you eat a delicious cake with tons of calories, you don't need to run a marathon right that instance. Think weekly! Throughout the following days, adjust your eating and exercise to make up for that big caloric surplus. The big problem in nowadays world is that it’s so easy to eat too much calories. Sweets are all around us and we usually over eat, even when we’re not hungry!


Energy balance and exercice

This is my jam: what exercise burns more fat, or how should your exercise? I love this question. There will be more posts about this question in more details later. For now lets just say that exercise is a tool that helps you with your energy balance. You should find a lifestyle than enables you to enjoy the food you eat without having to frenetically exercise every day to make up for it. A regular exercise routine with a mix of moderate and intense activity is perfect to keep everything in check and reap numerous health benefits.



The most important part of being fit and achieving your goals is to enjoy the process. The fundamental rule allows you to understand the relationship between food and exercise, so when you read or hear things about fitness, you can see how to implement it in your life.