Garage Gym Athlete's Notes on Fat Burning...Part 1 of 2

Fat burning and fat loss are not the same thing: fat loss is the actual loss of stored body fat (and it requires a caloric deficit), while fat burning is about bioenergetics—how efficiently your body oxidizes fat as a fuel source. Both matter. This is Part 1, covering fat burning and why becoming a better fat burner is a trait worth developing; Part 2 covers fat loss.

Key Takeaways

• Fat loss ≠ fat burning. Fat loss requires a caloric deficit; fat burning (fat oxidation) is how your body uses fat versus carbohydrate for fuel.
• Burning more fat for fuel is a desirable trait—it's the opposite of the “metabolic inflexibility” seen in metabolic syndrome.
• Elite, healthy athletes oxidize more fat during exercise and carry more muscle mitochondrial mass.
• You build fat-burning capacity with base training—low-intensity aerobic (Zone 2) work and higher-rep strength work—plus occasional fasted cardio for practice.

For Part 1, I am only sharing my notes on the Fat Burning…and I’ll share my notes on Fat LOSS in Part 2.

Let’s dive in!

Fat BURNING Machine… (Make the Machine Work How it Should)

• How do we become a fat burning machine?
  • Fat Loss vs. Fat Burning? 🤔 
    • A common thing I am hearing in the influencer world is that fat loss and fat burning are not the same thing. This is a correct statement, but it is not giving the full picture of training, nutrition, metabolic flexibility, and what a healthy human vs. unhealthy human look like.
      • To be clear, fat loss is referring to the actual loss of stored fat in the human body (what most people are after) and fat burning is referencing bioenergetics and how humans burn different fuels for different activities.
  • Does diet type matter? 🍲
    • Most people saying “fat loss and fat burning are not the same thing” are really only trying to make one singular point: You can follow a HCLF diet and lose fat -OR - you can follow a HFLC diet and lose fat.
    • The ultimate point: To Lose Fat (body weight), Total Caloric Intake must Be Less Than The total Caloric Need. That is 100% true. To lose fat, you need to be in a caloric deficit. I think it’s funny that this is even a “revelation” since this has been pretty well documented for decades.
  • Do we have the full picture with one statement? 🔍
    • However, I think we need to look more closely at the actual Fat Oxidation (Fat Burning) and how the body uses carbohydrates at different fitness levels to get a better picture of what’s going on here.
• So if you burn high amounts of fat, it does not matter? Not so fast.
  • We can’t stop short with an Instagram post or Tweet. 🤳
    • The problem with influencers stopping short at saying “fat loss and fat burning are not the same thing,” to “blow your mind” may have you think burning fat as a fuel source does not matter/is fully irrelevant or it should not be desired.
  • Do we want to burn fat? 🚴‍♂️
    • When we look at the actual physiology of an elite athlete, that’s exactly what you want to emulate. You want to be a human being that oxidizes more fat.
    • Sure, we can say fat loss and fat burning are not the exact same. We will get into how to lose stored body fat (next week's notes), but fat oxidation is still very much a desired trait for a human being.
  • Let’s look at an interesting correlation. 👨‍🔬
    • Unhealthy Human
      • Patients with metabolic syndrome (MtS) are characterized by a decreased capacity to oxidize lipids (burn fat) and by early transition from fat to carbohydrate oxidation (FATox/CHOox), as well as elevated blood lactate concentration [La−] as exercise power output (PO) increases, a condition termed ‘metabolic inflexibility’.
    • Elite Athlete (healthy - as far as we know)
      • However, in a professional athlete, they are oxidizing way more fat for energy vs. someone who has metabolic syndrome.
      • So what we see here is that people who have what most athletes desire: muscle mass, big aerobic engines, etc. These people all burn a lot more fat for energy than someone who is unhealthy.
  • What does it all mean? ❓❓
    • Meaning: We want to become a human that burns more fat. We want to burn fat for as long as possible and at the highest intensity our body will allow (which is not super high). Why? Because we want to be the opposite of someone with metabolic syndrome. We may not want to be a professional athlete, but we want to be as far away from metabolic syndrome as possible. We want our bodies to rely more heavily on fat as fuel over carbohydrate. How do we do that?
      • TRAINING!! Following a well-rounded training program is one of the best ways to burn fat as a fuel source!
      • Fasted Cardio (for fat oxidation practice, not superior fat loss)
• In short: Training Matters
  • It is known that elite athletes… 🏋️
    • 1.) Burn more fat during exercise.
      • Primarily because they are so fit, YOUR and MY moderate to high intensity is still in their low intensity zone, so their body can still rely on fat.
    • 2.) Elite athletes have increased muscle mitochondrial mass.
  • So how do we get there? ✍️
    • To be a human that oxidizes more fat, you need to Increase muscle mitochondrial mass and raise your “base” for where your body switched from fat to carbohydrate. We do that with…
      • BASE TRAINING. Base training is simply a reference to how you widen the base in your training. In the aerobic world it is low-intensity training like Zone 2 work. In the strength world it is the boring, but necessary, work like the sub-max effort method, or simply hypertrophy training (lighter loads lifted for more reps).
      • No matter how advanced you are, be sure you always still incorporate BASE training in your weekly split. Base training with occasional fasted cardio are two great ways to make sure your body gets good practice at using fat as a fuel source. This will keep you metabolically flexible and have you emulating top-end athletic training.

That's it for Fat BURNING!

But, that's not the end of the story. Base training is only part of the equation. What to eat, when, caloric deficits, and other forms of training all come in to play when we start talking about Fat Loss!

And that's what I will share with you next week!

Frequently Asked Questions

What is the difference between fat burning and fat loss?

Fat loss is the reduction of stored body fat, and it happens when you're in a caloric deficit—eating fewer calories than you burn. Fat burning (fat oxidation) describes how your body uses fat versus carbohydrate as fuel during activity. You can be a good fat burner and still not lose fat if you're not in a deficit.

Is being a better fat burner actually worth it?

Yes. A higher capacity to oxidize fat is associated with healthy, well-trained athletes and is essentially the opposite of the metabolic inflexibility seen in metabolic syndrome. Even if you never want to be a pro athlete, you want to move away from that unhealthy end of the spectrum.

Does fasted cardio burn more fat?

Fasted cardio is useful as practice at using fat for fuel and building metabolic flexibility—not as a magic route to superior fat loss. Fat loss still comes down to your overall caloric balance.

What kind of training builds fat-burning capacity?

Base training: low-intensity aerobic work (like Zone 2) and higher-rep, sub-maximal strength work. Keep base work in your weekly split no matter how advanced you are, and add occasional fasted cardio to practice burning fat.

Related reading from Garage Gym Athlete

• High or Moderate Intensity Better For Fat Burning?
• Recast: How To Burn Fat
• How to Calculate and Program Zone 2 Training

Kill comfort,

JM

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P.S. If you follow GGA programming, we have already planned all the types of training required for fat burning and fat loss. If you aren't following our programming, go sign up here.