How to Burn More Fat Through Exercise?

Javier Colomer 9 min. of reading Fitness Leave a comment

“Burn fat” is a hugely popular term that most people know and use. It’s generally associated with, or thought to refer to, weight loss and a decrease in fat percentage, but it’s a somewhat misused word, much like “toning”…

However, we’re going to take another approach, one more focussed on sport, and how this macronutrient behaves as an energy source. There are no magic formulas, just hard work and perseverance!

Fat Usage

A well-trained athlete has a great capacity for increasing fatty acid oxidation, as they can draw on fatty acids and use them as fuel, rather than carbohydrates (limited energy). In contrast to these athletes, obese patients who have high insulin resistance or type II diabetes are very inefficient at “burn” fat.

It’s important to understand the factors that regulate fat metabolism, and ways to increase fat oxidation, in both patients and athletes

As a result, fat is deposited in muscles and other stores (in other tissues). This accumulation of lipids and their metabolites within the muscle interferes with the capacity of the muscle’s insulin receptors and will lead to insulin resistance.

Fat Burn and Energy Production

Lipolysis

Fat is stored in adipose tissue, but also at the intra-muscular level (intramuscular triglycerides). When you start exercising, neuronal stimulation, where catecholamines (adrenaline, noradrenaline) intervene in the process by increasing lipolysis, leads to the breakdown of fats into fatty acids and glycerol in adipose and muscle tissue.

During exercise, a mixture of fatty acids derived from adipocytes and intramuscular stores are used. More trained subjects use more intramuscular fat as an energy source during exercise.

Oxidation of Fatty Acids

As soon as the exercise begins, the fatty acids are mobilised from the adipose tissue, which are transported to the muscle, through the cell membrane, and reach the mitochondria, the cell organelle where beta-oxidation occurs (commonly known as “fat burn”), and thus, is subsequently used as energy.

Fat oxidation (burning) is carried out in different steps: it is regulated by hormones (HSL “Hormone Sensitive Lipase”), stimulated by catecholamines, and inhibited by insulin. The transport of fatty acids will also depend on the supply of blood to the adipose and muscle tissues, for the uptake of said free lipids by the muscle and the mitochondria below.

Factors that influence Fat Burn

Exercise Intensity

One of the most important factors determining the rate of fat oxidisation during exercise is the intensity. It’s generally recommended that if we want to burn fat, we should exercise in a zone known as the “fat-burning zone”, which will depend on our heart rate.

It sits at around 60-75% of our VO2MAX (anaerobic threshold).

Some studies have confirmed that through HIIT, despite working at intensities higher than those recommended for fat burning, and where glycogen is primarily used, the post-burning effects at the level of eliminating lipids are even greater.

Exercise Duration

The longer the exercise lasts, the more the body will use fat as an energy substrate.During ultra-distance competitions, high peaks of fat oxidation can be reached.

In terms of weight loss, exercise duration can be considered an effective way to increase the energy used (calories burned)

Type of Exercise

The degree of fat oxidation differs depending on the sporting activity being practiced. Amongst the differences between the activities (athletics VS CrossFit), or even within the same activity (training one muscle group or another), there will be several variables affecting the use of more or less fuel from fat.

Bear in mind that the calorie expenditure of an activity is not the same as the final fat expenditure…

Diet and Performance

To reduce our fat index, our energy intake from food must be less than our energy expenditure. It’s about creating a caloric deficit. If our training is extremely demanding, we’ll have to plan to avoid affecting our performance or recovery.

Women have a higher rate of fat oxidisation when exercising. However, the differences generally aren’t too big…

The HSN Protocol: Fat Loss, developed by Sergio Espinar, is designed especially for athletes looking to lose fat but without compromising their athletic performance.

Training while Fasting

Training while fasting can increase the amount of fat you use up. However, as with before, if the amount of calories we’re consuming through our diet exceeds our total energy expenditure, the process won’t be effective.

Endurance athletes often use this method of skipping breakfast, or training while fasting, with the specific aim of encouraging fat oxidation and increasing their metabolic flexibility

The relationship between fasting and training for fat loss might also be associated with the athletic level of the subject. For untrained or sedentary people (brisk walking…) it might have a greater impact than for very active sportspeople or athletes used to training at high intensities.

Tips to Boost Fat Burning

Training Frequency

Obviously, one of the most effective methods to promote fat oxidation is through regular training.Through regular exercise, it’s possible to increase the enzymes that generate more stimulus for fat burning, increase mitochondrial density, increase blood flow… all of which will increase the rate of fat oxidation.

Strength Training

The pillar of sporting activity for everyone, regardless of their physical condition. While it might not result in fat loss in the short term, it will condition our evolution.

Basic strength exercises: squats, deadlifts, bench presses… these all help to mobilise a large amount of muscles, which will directly and indirectly increase energy expenditure

Circuit Training

This kind of training aims to maintain a high calorie expenditure for the duration of each set or round. Several stations are established, generally with functional exercises performed at each.

Aerobic Activity

As we saw earlier, the intensity of the activity will result in the use of more or less fat. If our goal is purely aesthetic, low-intensity aerobic exercise will complement a training programme focused on fat loss.

Activities such as walking or running at an intensity of approximately 50-65% of the VO2Max seem to be one of the most effective ways to achieve the greatest amount of fat burning

My recommendation for what type of cardio to do is simple: alternate HIIT, MISS and LISS...

Increase your NEAT

The fat burning or oxidisation that occurs when exercising is really small when compared to the rest of our day. All of our daily activity contributes to our calorie expenditure. Taking the stairs instead of the lift, cycling instead of taking the car… Although they’re everyday activities, we can still include them in our programme planning, even if they’re listed under the NEAT terminology (“Non Exercise Activity Thermogenesis”).

Fat oxidation rates are around 0.5g per minute at optimal exercise intensity.As such, “burning 1kg of fat mass” would require more than 33 hours of exercise!

Supplements for Burning Fat

There are a wide range of supplements on the market designed to supplement a nutritional and training plan and produce a greater degree of fat burning. Some of the best are:

Caffeine. This stimulates lipolysis and fatty acid mobilisation by increasing the circulation of catecholamines, or by antagonising receptors that inhibit hormone-sensitive lipase.
Guarana. Its active ingredient, guaranine, is very similar to caffeine, and therefore causes fatty acid oxidisation. The response is somewhat less acute at first, but more sustained and prolonged.
Green Tea. The active substance in greeen tea is polyphenols, particularly epigallocatechin gallate (EGCG). It also contains caffeine, which is used to promote fat burning.
Tyrosine. This is an amino acid precursor of catecholamines. As a result, it increases catecholamine levels and, as we have seen, increases lipolysis.

Study: Am J Clin Nutr 87: 778-784, 2008

One study found that drinking green tea before exercise could increase the lipolysis rate by 20%. The mechanism that causes this effect is not established, but it’s thought that the active ingredients present in green tea, called epigallocatechin gallate (EGCG), which is a potent polyphenol with antioxidant properties, inhibits the enzyme COMT (catechol O-methyltransferase), which is responsible for the degradation of noradrenaline.

As such, higher concentrations of this substance are maintained, and therefore greater stimulation of lipolysis, making more fatty acids available for oxidisation.