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How to: burn fat

The internet doesn't need another fat loss article.

We look at the cool stuff surrounding fat adaptation that can benefit you.

Torching body fat Vs using fat for fuel is commonly mistaken yet interchanged freely in the physique and fitness industry.

Ask many people on the gym floor about why they started training and most will propose a benefit to body fat or weight reduction.

Increasing fat burning may help you achieve your desired body weight and have a beneficial impact on your endurance but let’s address the fundamental comparison.

Using fat for fuel refers to using the fat that is consumed in the diet for energy.

Burning body fat refers to using the fat that is stored in the body as a source of energy.

The fat that is consumed in the diet is readily available for use as fuel, whereas burning body fat requires the body to first break down the fat stores before they can be used for energy.


  • To lose weight, you must create a deficit in your body's energy balance by burning more calories than you consume.

  • By increasing your body's ability to burn fat, you can increase the percentage of calories burned that comes from stored body fat.

Our bodies burn all three macronutrients that make up calories (fat, carbohydrate, and protein) for energy, but most of our energy comes from carbohydrates and fats.

Increasing the percentage of energy expended from fat means a decreased percentage of carbohydrates, and vice versa, like a seesaw effect.

To maximise fat burning, it's important to focus on aerobic/endurance exercises such as jogging, cycling, swimming, rowing, skipping, and cross-country skiing.

During these exercises, energy is produced by combining carbohydrates, fats, and a minimal amount of protein calories with oxygen. Oxygen is a crucial factor.


At rest, the body uses fat as a fuel source, as we elevate heart rate and muscular activity this stimulates blood flow and enzymes which takes oxygen, glucose and other nutrients to the working muscles, allowing them to use carbohydrates as a fuel source in addition to fat.

As intensity and exercise duration gets higher, we use up ATP (think of this as your onboard battery pack that can be recharged) more blood glucose has to be synthesised (from muscle tissue, blood glucose, and liver) to feed further energy production.

The body may also start to break down muscle tissue to use as an energy source in addition to fat and carbohydrates.

This is why it is important to properly fuel the body with carbohydrates before and during high-intensity and long-duration exercise to prevent muscle breakdown and maintain energy levels.


Using fat from the diet for fuel is generally less efficient than burning body fat. This is because the body needs to first break down the dietary fat into smaller molecules before it can be used for energy, whereas body fat is already in a form that can be readily used.

Fatty acids


Carbohydrates fructose and glucose


Burning body fat can lead to weight loss as weight is not only fat, BUT it is not a predictor of reductions in body fat percentages.


1lb of fat is said to equate to 3500k/cals.

To lose 1 lb of body fat alone, you have to preserve muscle tissue fiercely (resistance training and protein intake) whilst you support the basic metabolic needs of your body, reduce energy intake or promote further output over some time.

Over 7 days you would need to create a -500k/cal per day deficit - this could be done by reducing your dietary calories by 250 and increasing expenditure by 250 (both from your current baseline) to create a 500 calorie deficit.

7 days -500 = - 3500 calories - -1lb of fat

Stay with us.


Fat adaptation is a metabolic process in which the body becomes more efficient at using fat as a fuel source during exercise.

This happens when the body is repeatedly exposed to low-carbohydrate, high-fat diets and prolonged exercise sessions.

When the body is in a low-carbohydrate state, it turns to fat stores to provide energy for exercise.

Over time, the muscles become better at using fat as a primary fuel source, which can enhance endurance performance and increase the availability of energy during long-duration exercises.

Fat adaptation also involves changes in the body's enzymes and metabolic pathways to better utilise fat as a fuel source.

These changes include an increase in the activity of enzymes involved in fat oxidation and a reduction in the activity of enzymes involved in carbohydrate metabolism.

As a result, the body becomes more efficient at using fat as a fuel source and conserves its limited carbohydrate stores for high-intensity exercise.

According to research, it typically takes 2-4 weeks of consistently following a low-carbohydrate, high-fat diet and consistent training. It may not be suitable for all athletes. low-carb diet to become fat-adapted.

However, the duration may vary depending on individual factors such as metabolism, exercise routine, and overall health.

There is no specific g/kg of bodyweight recommendation for macronutrients to become fat-adapted. However, most low-carb or ketogenic diets recommend consuming a high amount of fat, moderate protein, and very low carbohydrates.

Combine this with understanding your Total Daily Energy Expenditure (we do this for our clients) you can refine the numbers.

Typically, the macronutrient ratio for a low-carb diet is 60-75% fat, 15-30% protein, and 5-10% carbohydrates. 1,2,3

Most athletes do well aiming for 20% protein, 60% fat and 20% carbohydrates to begin, emphasised around the workout window.

For example, only, a male maintaining their weight at 2500k/cals per day would aim for 125g protein, 125g carbohydrates and around 167g of high-quality fats during this phase.

As for the duration of time, it takes to become fat-adapted, it may take anywhere from 2-4 weeks of consistently following a low-carb diet to enter a state of nutritional ketosis and become fat-adapted.

The exact duration may vary from person to person depending on various factors such as age, gender, activity level, and overall health status. 4,5,6

We don’t advise that this is a long-term lifestyle strategy, we are objectively looking at the outcomes and information and these have to be considered within the context of your lifestyle.