The world of bodybuilding is a lucrative sport, and if you want to play with the big dogs, you have to know what you're doing.

And suppose you're into the natural bodybuilding world. In that case, you're likely relying on strict nutrient timing, a dedicated training routine, proper sleep, and clean supplements to get you where you need to be.

There isn't much wiggle room when it comes to show time. The cutting phase that most bodybuilders go through is intense, and it takes careful calculations to get you to a specific body fat percentage where you can take home the win.

But that period when you're cutting calories is also a period when you could cut gains. It's all about tweaking your macros and adding in specific supplements so you can maintain muscle while still losing fat—and it hovers a fine line.

So, how do you shed fat and get competition ready without sacrificing all the muscle you've worked so hard for?

It's simple: A fat burner.

But we're not talking about any old fat burner. We're talking Burn Lab Pro. The most advanced, cutting-edge stim-free fat burner designed to maintain muscle mass AND burn fat.

The Science Behind Fat Burners

Bodybuilding is an exact science and knowing how to go through a cut healthily is a challenge. For most people, cutting weight and fat depends largely on watching portion sizes.

For bodybuilders, however, it's a bit different. It's still about watching how much you eat, but it's also about balancing the scale to avoid muscle breakdown in the process.

Regardless of what sport you do, for anyone looking to drop fat, cutting carbohydrates is the simplest way to do it.

Carbs, which are broken down into glucose, serve as the primary and preferred fuel substrate for your brain and red blood cells; glucose can readily cross the blood-brain barrier, and tight regulation of glucose metabolism is imperative for brain physiology 1.

But in the case of weight loss, carbs are also the easiest to convert to fat when consumed in excess, which means that if you're not careful about calories in vs. calories out, it's easy to pack on the pounds without even realizing it.

In the sport of bodybuilding, cutting carbs is the quickest way to lean out and get shredded when you're in prep mode. That's because when you remove glucose from the diet—or at least large amounts—your body still needs fuel, so it taps into fat stores.

Hence, you burn adipose tissue for energy via a process called ketogenesis, and you drop fat. It's a pretty simple concept.

You also have to consider things like meal timing and intermittent fasting as other practices to boost fast loss while holding onto muscle.

And then there are fat burners.

Most fat burners on the market rely on fatty acid mobilization and thermogenesis to get the job done. When you're breaking down fat and moving it into the bloodstream for fuel, you're reducing body fat stores and losing fat mass.

But where does your energy come from?

The low-calorie, low-fat diets that bodybuilders follow during a cut can be really hard on the body. You're depriving your body of glucose, and you're not consuming a ton of fat, so how do you fuel up?

When 'normal' food intake is restricted, the body turns to other stores for fuel—and that store is protein.

Protein breaks down through a process called gluconeogenesis to form glucose, which can then supply the brain and red blood cells with energy 2.

But when you're trying to maintain as much mass as possible, breaking down existing muscle to release amino acids isn't an option.

As such, getting your hands on the best fat burners for bodybuilders is key for weight loss, maximizing your performance, and preserving muscle with or without a competition in mind. It's an instant knockout.

Let's talk about how we do that.

How A Fat Burner Works

A point of a fat-burning supplement is pretty self-explanatory—it burns fat. But the actual process as to how it does it is based on the type of product you're taking and what ingredients it uses.

For the average person, diet plays a huge role in body composition and fat loss than training does. It's the old saying of "you can't outwork a bad diet". Whether you are bulking or cutting, a good diet is still key to results.

For fat loss, however, it takes a much more concerted effort, and that's where fat burner supplements can come in handy.

One of the biggest problems you'll find with conventional thermogenic fat burners is that they help break down and mobilize body fat, but they provide little support for your muscles.

So, if you want to maintain muscle mass during an intense cutting phase, you need the best stim-free fat burner that helps to preserve lean muscle while torching body fat.

The best fat burner does this by 3:

  1. Triggering thermogenesis: Thermogenic ingredients help crank up core body temperature to enhance metabolic rate and increase energy expenditure. The more calories you burn, the more weight and fat you lose.
  2. Regulating appetite: Insulin and glucose regulation is key to eliminating blood sugar spikes that impair mood and trigger cravings, especially when you're cutting.
  3. Enhancing fat oxidation: Burning up stored fat is the primary goal of a fat burner, and the best fat-burning supplements always include ingredients that mobilize fat stores, and increase fat oxidation and utilization. And as a bonus, fat burns cleaner than glucose and offers more energy per gram.

And when you get one like Burn Lab Pro, you're also getting ingredients that help preserve lean muscle mass, so you're not sacrificing all the hard work and time you've put in at the gym.

The Top 3 Fat-Burning Ingredients For Bodybuilders

1. HMB (B-hydroxy-B-methylbutyrate)

HMB is a metabolite of one of the most well-known muscle-building amino acids around—leucine.

And it just so happens to be one of the best picks for preserving lean muscle while burning belly fat, boosting energy levels, and supporting recovery. It's an all-around top pick (if not the top pick) for the best fat burner for bodybuilders.

Here's why.

Traditionally, bodybuilders and athletes have relied on leucine for maximizing muscle growth. It's one of the most anabolic amino acids, and it's key for building mass and strength.

There's nothing wrong with leucine, and it's a critical part of the muscle-building process, but if you're looking for HMB from leucine, you're not going to get it. That's because when leucine breaks down, it's converted into two products, not all of which is HMB.

Actually, very little is converted to HMB. About 80% of ingested leucine is shunted towards protein synthesis, while the remaining 20% is metabolized into alpha-ketoisocaproate (a-KIC) and HMB.

The former is about 95%, while only about 5% makes it to HMB 4. Because of this, supplementing with pure HMB is substantially more effective.

But what does HMB actually do?

One of the primary roles, and the reason it's a must for bodybuilders, is because it helps to burn stubborn fat while preserving lean muscle mass.

One of the main pathways involved in muscle protein synthesis, the mTOR pathway, is controlled primarily by various hormones and growth factors but also by amino acids like leucine.

In muscle cells, leucine is the major amino acid that activates this mTOR pathway, so when you omit leucine from the diet by cutting back on protein intake, you essentially cause rapid inactivation of mTOR signaling and thus put a rapid halt to muscle protein synthesis (MPS) 5.

In more simple terms, mTOR is the main pathway regulating muscle protein synthesis. Without all the components needed for the mTOR pathway to operate, you cannot form functional proteins, and you cannot increase muscle strength and size.

But there's another great thing about HMB that bodybuilders cash in on—its ability to protect muscles during fasted training. Training in a fasted state is one of the fastest and easiest ways to promote fat loss, but it's also the quickest way to crush your hard-earned muscle.

So, taking a supplement like HMB helps to reduce markers of muscle damage, such as creatine phosphokinase and lactate dehydrogenase (LDH), and spare muscle protein wasting during periods of low-calorie intake 6.

And studies consistently support the role of HMB for enhancing muscle protein anabolism, thus making it one of the best anabolic/anti-catabolic supplements that can be added to the best fat burner 7.

2. ForsLean (Coleus Forskohlii)

Extracted from the root of the Coleus forskohlii plant, forskolin is a top-ranking player in the fat loss game and another big one to look out for in the bodybuilding world.

It's traditionally been used as a staple for treating several different chronic diseases, but more recently has become a staple for igniting the body's internal fire to help you burn fat.

The reason forskolin is one of the best fat burners is because it acts directly on the adenylate cyclase enzyme, which, in turn, activates cyclic adenosine monophosphate (cAMP). And cAMP? It promotes fat breakdown and utilization.

Without getting into the complexities of the mechanism, what forskolin does is stimulate the body's natural thermogenic response to increase basal metabolic rate (BMR) and increase mobilization and utilization of fat, which ultimately helps you burn more calories and more fat in a much more effective and efficient manner 8.

And there's more. Studies also show that forskolin:

  • Regulates lipid and glucose metabolism
  • Increases energy expenditure
  • Works as an appetite suppressant
  • Elevates testosterone levels (minimally)
  • Preserves muscle while burning fat

Sounds like a pretty good deal to us, so you know it's going to be one of the key ingredients in the best fat burners.

3. Capsimax (Cayenne Pepper Extract)

Who knew that the spice we all know and love could be one of the most effective additions to a bodybuilders supplement stack?

When paired with other powerful fat-burning ingredients, the active compound in cayenne pepper, capsaicin, functions as a potent thermogenic agent that offers a 3-in-1 punch:

1. Increases energy expenditure
2. Burns up stored fat
3. Suppresses appetite

The mechanism behind how it works lies in the nervous system. Capsaicin activates the sympathetic branch of the nervous system to hike up the release of catecholamines, which results in more energy and increased fat metabolism, thereby promoting stimulant-free fat burn 9.

And when you turn on the sympathetic nervous system, you activate fight-or-flight mode, which subsequently down-regulates hunger—Bam, appetite suppression.

Need more reason to use it? How about these:

  • Improves metabolic and hormonal function
  • Reduces insulin and leptin resistance
  • Improves endothelial function
  • Increases energy expenditure
  • Stimulates thermogenesis
  • Maximizes weight loss
  • Increases fat burn

And perhaps one of the best things about capsaicin is that it triggers a very similar action as stimulants do, without actually being a stimulant, so naturally, it's a staple in any good thermogenic fat burner.

What To Avoid In A Fat Burner

Conventional fat burners are like a kitchen sink—they dumb all sorts of crappy ingredients in as long as they do the job. The side effects? Well, that's up to you to deal with.

If you're in the market for a fat burner that contains any of the ingredients we're about to list, it might be time to reconsider your fat burner choices.

  1. Green tea extract - Green tea extract is one of the most common additives to many natural fat burners, but just because it's common doesn't mean it's good (or safe). There's a reasonably good-sized body of research backing green tea extracts' efficacy as a fat burner due to being rich in a biologically active polyphenol called epigallocatechin‐3‐gallate (EGCG). EGCG stimulates fat breakdown by directly inhibiting catechol‐O‐methyltransferase, the enzyme responsible for breaking down norepinephrine 10. By activating the sympathetic nervous system, it increases the release of catecholamines, which influences fatty acid mobilization and oxidation 3. But what the labels aren't going to tell you is that excessive intake of green tea extract can result in hepatotoxicity, so it's best just to avoid it 11.
  2. Caffeine - Before you get too worked up, let's be clear that there's nothing inherently wrong with caffeine, even in a fat burner. It's a powerful central nervous system stimulant that increases alertness, reduces fatigue, and mobilizes fatty acids from adipose and/or intramuscular stores for fuel 3. The problem is that most fat burner manufacturers load up their formulas with stimulants to maximize catecholamine release and therefore maximize fat burn. But when taken long-term, the side effects of excessive caffeine intake can actually work against the goal of your fat burner, so it's more beneficial to you and your results to find either a low-stim or stimulant-free fat burner.
  3. Green coffee bean extract - Green coffee bean extract is derived from coffee beans before the roasting process and offers some good benefits for fat loss. Studies suggest it may hold some value as a potential anti-obesity agent by inhibiting fat absorption and activating fat metabolism in the liver 12, or it may mediate plasma adipokine levels and body fat distribution, downregulate fatty acid production, and increase fatty acid beta-oxidation activity 13. This coffee derivative, like caffeine, isn't inherently bad, but there isn't a ton of conclusive evidence to make it part of the best fat burners.
  4. CLA - Conjugated linoleic acid is a compound naturally present in red meat, but it's more recently been added to all sorts of weight management and fat burner supplements due to its potential to regulate appetite, inhibit fat production, and increase energy expenditure, lipolysis, and fat oxidation 3. However, while there is some positive research, there's also a substantial amount suggesting that CLA supplementation increases inflammatory markers, which will be disastrous to any efforts to lose weight and lose fat 14, 15.

Our Top Pick: Burn Lab Pro

Now that you know what to look for and what to avoid for the best fat burner for bodybuilders, it's time to get to the best one on the market.

Burn Lab Pro is a cutting-edge, ultra-modern stimulant-free thermogenic fat burner designed for maximum fat loss and muscle preservation.

It's the world's cleanest, safest, and most effective fat burner that combines five powerful active natural ingredients formulated to torch fat, melt weight, enhance physical performance, boost muscle growth, and speed up recovery—everything a bodybuilder needs for peak results.

It's designed to enhance your metabolic performance throughout the day through non-stimulatory pathways to boost weight loss and excel your fat loss goals.

Key Benefits

  • Increases fatty acid mobilization and utilization
  • Stimulates thermogenesis to rev metabolism and boost energy expenditure
  • Boosts muscle strength, growth, and performance via non-stimulatory pathways
  • Protects against muscle breakdown and accelerates recovery

What you're getting in Burn Lab Pro

  • 1500mg HMB (B-Hydroxy-B-Methylbutyrate)
  • 375mg ForsLean (Coleus forskohlii)
  • 75mg Capsimax Cayenne Pepper Extract
  • 90mg NutriGenesis GTF-Chromium
  • 3.75mg Bioperine Black Pepper Extract (enhanced absorption)

Fat loss and training work synergistically—training helps you burn calories and build lean muscle, and more muscle means faster and more efficient calorie and fat burn.

Burn Lab Pro® optimizes fat loss and exercise synergy with the most intelligent fat burner formula ever using only the best research-backed key ingredients. It's the holy grail of fat burners designed to blast fat and build muscle at the same time.

Because of its cutting-edge design, Burn Lab Pro® is the most effective fat burner ever developed to give you bigger, better, and more powerful results.

Final Thoughts

The sport of bodybuilding requires meticulous detail and excruciating willpower, and when you've got a show to attend, there's no time for messing around.

Tightening up your diet and pinpointing training areas to focus on can help you level up to some of the top competitors, but if you want a little extra edge during your cut, investing in a good fat burner to help you lose weight and fat faster and healthier is one of the smartest things you can do.

Protect your muscles and your #1 spot for good with Burn Lab Pro.

Get the best Burn Lab Pro deals here


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