Fasted Cardio and Muscle Loss

  • By Performance Lab
  • 15 minute read
Fasted Cardio and Muscle Loss

How the fat-burning, muscle-sparing benefits of performance supplements can help you achieve your fasting goals

One of the best parts about increasing your energy expenditure via exercise…is being able to increase your energy intake via eating.

Everyone’s familiar with the phrase work hard, play hard. However, a more tantalizing twist on this phrase reads something more like exercise hard, eat more.

When you’re exercising, your metabolism converts food fuel not into fat but into anabolic muscle growth.

Though many “weight loss” dieting strategies emphasize reducing your calorie count, the more effective and sustainable approach to attaining a healthier weight involves elevating your calorie expenditure (exercise) to meet your calorie intake (eating).

However, this weight loss strategy, which prioritizes energy balance (intake = expenditure) over simple calorie reduction, can be problematic when you’re also trying to expedite your fat loss goals with fasted cardio.

Sustaining high levels of exercise energy, intensity, and endurance can be a difficult task while you’re also fasting to encourage fat loss.

Even worse, fasting may actually threaten increased muscle loss, as your body resorts to protein as an energy source during exercise.

With that in mind, there are a few strategies you can adopt to not only minimize muscle catabolism (breakdown) but actually enhance your muscle gains.

One of those strategies involves adding the Performance Lab® SPORT Range to your daily supplement regimen.

The list of the best supplements for fasted cardio and muscle protection includes:

  • Burn Lab Pro® – a stim-free pre-workout fat burner designed to maximize your calorie-burning capacity and minimize your muscle catabolism (breakdown) for a leaner, meaner physique.
  • Performance Lab® MCT – supplying C8 + C10 MCTs, this medium-chain triglyceride (MCT) oil is a must-have glucose-free energy supplement for all dietary regimens involving intermittent fasting and/or fasted exercise.

In this guide, we cover the health and fitness advantages of fasted cardio, as well as how to minimize the risks—namely the potential negative impact on muscle metabolism—associated with fasted cardio.

Or you can skip below to the Best Supplements for Fasted Cardio and Muscle Gains to read our full analyses of the …well, of the best supplements for fasted cardio and muscle gains!

The Beginner’s Guide on Intermittent Fasting

A plate with a knife and fork in the shape of a clock to signify intermittent fasting

In the 21st century, what’s old is new again, as demonstrated by the latest rise of health and fitness trends.

As we increasingly learn how our unnatural environments and lifestyles are taking a toll on our physical and mental health, today’s athletes and exercisers are turning towards more natural ways of living.

Just like “cold shower” therapy, which mimics the naturally cold waters of the outdoors, and the more controversial “segmented sleep,” which matches the natural sleep patterns of a pre-9-to-5 world, intermittent fasting is one of modern man’s strategies for re-entering nature.

What is Intermittent Fasting?

Intermittent fasting is a dieting strategy that involves temporarily fasting for a scheduled period of time to help the body metabolically recalibrate and reorient itself to a more natural eating schedule.

The human body was shaped by the wilderness - not the urban sprawl of restaurants, bars, cafes, fast-food drive-thrus, convenience stores, etc.

In the wild, food is sparse and difficult to come by, often involving a significant amount of energy expenditure to acquire. However, in the city, little to no effort is required to eat.

  • Simply put, our bodies are not oriented towards constant eating. We have life-essential physiological processes that are triggered by intermittent periods of fasting—of hunger—but, unfortunately, we’re failing to trigger them because, well, we’re always stuffing our faces.

Intermittent fasting essentially mimics the natural eating habits of a natural environment, restoring our brain and body to a healthier, more natural physiology.

To practice intermittent fasting, you don’t necessarily need to change what you eat nor how much you eat.

All you need to do is schedule your diet into designated time periods of feeding and fasting, ideally with the fast ending immediate after working out to incur the benefits of fasted cardio—i.e., exercising on an empty stomach.

What is Fasted Cardio?

Fasted cardio, or fasted training, essentially involves exercising on an empty stomach, typically in the morning prior to breakfast, to encourage the use of stored fat over food fuel as a source of exercise energy.

Performed as part of an intermittent fasting schedule, fasted cardio takes advantage of the “fasting” period of your diet schedule to further promote the body’s use of stored fat as a source of energy fuel.

  • Research suggests that fasted training in the morning may significantly improve not only fat burning but also appetite control throughout the day. As one 2016 study on the effect of fasting prior to morning exercise on 24-hour energy intake observing, “fasting before morning exercise decreased 24-hour energy intake and increased fat oxidation during exercise.”

By encouraging early-morning fat burning, fasted exercise in the morning helps reduce daytime cravings and, thus, lowers the risk of overeating, as the fasted exercise has already primed the body to be more self-sufficient with its energy demands.

Which all sounds great on paper. But the practical application of fasted cardio to your daily routine is much easier said than done, especially when conventional wisdom suggests loading your body with food energy prior to any athletic activity.

Is It Safe to Train on an Empty Stomach?

Generally, yes.

Training on an empty stomach can be a healthy, beneficial strategy for sculpting your physique, so long as you’re still keeping your overall calorie and nutrient counts up. On that note, it’s important to remember that:

  • Intermittent Fasting is a Schedule, Not a Diet – meaning that you don’t need to necessarily reduce your calorie intake or change what you eat. You only need to change when you eat (and don’t eat).
  • Reducing Calories Means Reducing Nutrients – diets that overemphasize the central importance of calories overlook the greater importance of nutrients (i.e., carbs, proteins, fats, vitamins, minerals, etc.). Intermittent fasting doesn’t pressure you into a state of malnourishment, as many diets do.
  • Energy Balance is Superior to Calorie Reduction – seeking a balance between energy intake and energy output encourages overall bodily homeostasis, a harmonious metabolic state conducive to fat loss and muscle growth.

So long as you are matching your energy output with sufficient energy intake, as well as sufficient nutrient intake, and you are timing your workout to end at the start of the “feeding” period, you’ll run little risk of fast-related side effects.

However, like everything else in the world, there are advantages and disadvantages to exercising on an empty stomach. Let’s start with the positives:

The Athletic Advantages of Fasted Exercise

A woman performing fasted cardio on a treadmill in the gym

Who in their right mind would willingly train on an empty stomach, if there were no benefits to doing so? No, we’d much rather mow down a rack of ribs or a large pizza prior to working out than not!

Fortunately, there are several health and fitness advantages to fasted exercise, including:

Increased Fat Oxidation

Because fasted exercise relies more heavily on fat metabolism than carbohydrate (glucose) energy, fasting may help increase your rate of fat oxidation during exercise. Counter to fat intake and storage, fat oxidation essentially refers to the metabolic process of converting fat into human energy.

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Research suggests that fasted training prior to breakfast seems the best way to go for promoting fat oxidation throughout the remainder of the day:

  • In a 2017 study on the effects of pre-breakfast exercise on 24-hour fat oxidation among woman, a group of researchers observed a significant boost in fat-burning metabolism among the participants who exercised prior to breakfast, leading to the conclusion that “exercise performed in a post-absorptive state increases 24-h fat oxidation in female subjects.”

Enhanced Insulin Sensitivity

One of the primary issues with constant eating: too much insulin activity. Under feeding conditions, the body releases insulin to deal with the rising levels of glucose in the blood. However, over time, the insulin receptors begin to lose their sensitivity, resulting in weaker and weaker insulin activity and, eventually, a risky rise in blood sugar levels.

Under fasting conditions, however, the body doesn’t secrete insulin, giving the receptors time to restore their insulin sensitivity. The metabolic benefits of properly sensitive insulin receptors are key towards sustaining healthy weight and energy levels.

  • In a systematic review and meta-analysis on the effectiveness of intermittent fasting to reduce body mass index (BMI) and glucose metabolism, a group of researchers found sufficient evidence to conclude that an “ may provide a significant metabolic benefit by improving glycemic control, insulin resistance, and adipokine concentration with a reduction of BMI in adults.”

Better Daytime Appetite Control

Related to the fat oxidation benefits of fasted training, when performed in the early morning prior to breakfast, the appetite control advantages of fasted training are also immensely beneficial in sustaining a leaner, healthier body composition.

By encouraging the body to rely on stored fat metabolism over carbohydrate energy fuel, early morning fasted training can help mitigate your daytime carb cravings, saving you from spending a sad afternoon chowing down multiple bags of chips on the couch.

  • The emphasis on “early morning” here is important, as research also suggests that early time-restricted feeding (i.e., starting the “feed” portion of your intermittent fasting schedule early in the morning) may also “facilitate weight loss primarily by decreasing appetite rather than by increasing energy expenditure” and “may also increase fat loss by increasing fat oxidation.”

The Athletic Disadvantages of Fasted Exercise

Though a successful intermittent fasting + fasted training routine may significantly improve your fat loss and muscle gain results, the acute effects of fasting on muscle metabolism do pose a serious barrier to success for many.

Two setbacks with fasted exercise that need to be addressed include:

  1. Muscle Catabolism (Breakdown) – especially when you fail to acquire adequate calorie and nutrient intake during the feeding portion of IF, the body may enter a state of muscle breakdown to use protein as a source of exercise energy fuel.
  2. Burning Out – over time, the breakdown of muscle tissue, as well as the insufficient nutritional means to sustain all other high-intensity physiological processes, may result in a total “burn out”—mental and physical fatigue and soreness of the highest order.

Though ultimately more rewarding, fasted training over non-fasted training does require much more diligence and nutritional support to successfully pull off.

How to Maximize Your Fat Loss and Muscle Gain/Retention Results While Exercising on an Empty Stomach

Bodybuilder who has successfully retained muscle mass while losing fat during fasted cardio schedules.

With the potential disadvantages of fasted exercise in mind, you can avoid these setbacks and instead maximize your fat loss and muscle gain results while exercising on an empty stomach by:

1) Maintaining an Anabolic, Protein-Rich Diet

Adequate consumption of dietary protein is critical for the healthy growth, development, and maintenance of lean muscle mass. Maintaining an anabolic, protein-rich diet benefits both lean muscle growth and fat loss by increasing:

  • Skeletal Muscle Formation – no protein, no muscle tissue—the creation of muscle fibers requires the accumulation of protein, much of which depends upon the ingestion of dietary protein.
  • Resting Metabolic Rate (RMR) – the resting metabolic rate, or the rate at which you burn fat while at rest, is largely dependent upon your lean muscle mass. By increasing lean muscle mass, protein supplementation may significantly sustain long-term fat loss.

2) Boosting Your Body’s Calorie-Burning Potential During Exercise

Whether fasting or not fasting, taking an effective fat burner supplement prior to working out may significantly help boost your body’s calorie-burning potential during exercise. Essentially, by priming your thermogenic fat-burning pathways, a fat burner supplements encourages your body to use stored fat as a source of energy fuel before you even pick up your first weight of the day, thereby maximizing the fat loss potential of your workout.

3) Protecting Muscle Tissue Against Fasting-Related Catabolism

Though sparking thermogenesis is arguably the primary function of a fat burner supplement, what particularly distinguishes a good fat burner from the best fat burner for fasted cardio is the formula’s ability to burn fat while also protecting muscle tissue against fasting-related catabolism.

As we previously discussed, fasting threatens to exacerbate muscle catabolism during exercise, potentially worsening muscle fatigue and soreness, which in turn impair your near-future performance and fitness. By protecting against the deleterious effects of fasted cardio—e.g., lactic acid buildup, oxidative stress, protein-damaging enzymes, etc.—an effective pre-workout fat burner stack may help preserve your muscle gains while also having an ergogenic effect on exercise endurance.

4) Increasing Your Branched-Chain Amino Acid (BCAA) Intake

While emphasizing protein in your diet is an effective way to increase fat loss and lean muscle gains, increasing your branched-chain amino acid (BCAA) intake is particularly smart for procuring a sexy physique while intermittently fasting.

As the most anabolic of the essential amino acids that comprise protein, BCAAs directly correlate with not only your muscle metabolism but muscle performance during exercise as well. In fact, they acutely affect muscle performance during exercise, which is why taking a BCAA supplement intra-workout (during exercise) may rapidly improve your performance while immediately working against exercise-related muscle breakdown.

5) Taking a Medium-Chain Triglyceride (MCT) Oil Supplement

Everyone who has ever tried, or is currently trying, the keto diet is familiar with medium-chain triglyceride (MCT) oil. The key functional ingredient in “bulletproof coffee,” MCT oil works as an alternative brain fuel source of energy to glucose, making it a particularly important supplement to those frequently fasting or generally trying to cut down on their carbohydrate intake.

By quickly converting to ketones, an energy fuel sourced from fat, once absorbed, MCT oil offers fast-acting, long-lasting brain energy boosts that, when taken prior to exercise, may simultaneously enhance brainpower and metabolic energy expenditure under both fasting and non-fasting conditions.

Related Post: Should you take MCT oil pre or post workout?

Best Supplements for Fasted Cardio and Muscle Protection/Gains: Performance Lab® SPORT Range & Burn Lab Pro®

Performance Lab Sport Range

Hosting a diverse collection of athletic health and fitness boosters, Performance Lab® SPORT Range delivers all-natural ergogenic aids in ultramodern formulas fit for athletes of all types, aerobic and anaerobic, fasting and non-fasting.

However, for fasted cardio exercise in particular, the three recommended supplements are:

  • Burn Lab Pro®
  • Performance Lab® SPORT MCT

Individually, each formula may help you achieve a healthier, leaner physique without compromising your athletic health or fitness. Yet, when combined, these supplements work even better, synergizing to maximize your fat loss and muscle gain results.

Let’s take a deeper look at each formula:

#1) Burn Lab Pro®

Superior to your standard hyper-caffeinated fat-burner stack, Burn Lab Pro® is a smarter design: 100% stimulant-free fat burns that simultaneously promote thermogenic calorie-burning and protect muscle tissue against the catabolic effects of exercise.

Enhanced energy expenditure, fat breakdown, lean muscle growth—Burn Lab Pro® boosts multiple stim-free physique-sculpting pathways for an overall leaner, meaner body composition. Let’s check out the ingredients:

Formula Analysis

  • Calcium, 175 mg
  • NutriGenesis® GTF Chromium+, 60 mcg
  • Forslean® (Coleus forskohlii), 250 mg
  • HMB (β-Hydroxy β-Methylbutyrate), 1000 mg
  • Capsimax® Cayenne Pepper Extract, 50 mg
  • BioPerine® Black Pepper Extract,5 mg

By maximizing your pre-workout calorie-burning capacity and minimizing exercise-related muscle catabolism (breakdown), Burn Lab Pro® helps optimize your fasted cardio and muscle gain results.

While many “weight loss” supplements essentially amount to cheap caffeine pills, Burn Lab Pro® takes a more sophisticated approach to burning fat—or, rather, Burn Lab Pro takes several approaches, all of which synergize together to burn fat and build muscle with completely natural, stim-free ingredients.

Combined, Burn Lab Pro’s ingredients assist with fasted cardio and muscle loss by:

  • Sparking thermogenic energy expenditure during exercise
  • Encouraging the use of stored fat for intense workout energy
  • Protecting muscle tissue from harmful enzymes and stressors

Might be hard to believe but stimulants don’t hold a monopoly on thermogenesis, as demonstrated by Burn Lab Pro’s highly thermogenic formula.

Even better than the thermogenic effects delivered by stimulants, Burn Lab Pro’s combination of pro-catecholaminergic Capsimax® (Cayenne Pepper) + Forslean® (Coleus Forskohlii) promotes hormone-induced lipolysis (fat breakdown) in visceral fat tissue, helping you burn that stubborn belly fat with faster, healthier results.

What’s more, Burn Lab Pro® delivers its all-natural formula in the patented, clean, green NutriCaps® delivery system, involving an additive-free capsule constructed out of fermented tapioca (pullulan).

Assisting with the nutrient-absorption benefits of Burn Lab Pro's BioPerine® black pepper extract, Burn Lab Pro’s synthetic-free formula design eschews all gut-damaging artificial sweeteners, flavors, preservatives, etc. typically found in powder-based workout supplements.

The result is a bodybuilding fat burner that boosts fat loss without compromising your cardio or gut health.

Get the best price on Burn Lab Pro here

#3) Performance Lab® MCT

Performance Lab MCT Bottle

One of the most difficult things to sustain while fasting is your energy levels. This is why medium-chain triglyceride (MCT) oil is a must-have supplement for those committed to intermittent fasting and/or keto dieting: MCT oil offers a brain energy alternative to fast-breaking glucose energy.

And by supplying the two best MCTs—C8 and C10—sourced from 100% organic coconuts, Performance Lab® MCT is easily the best MCT oil stack you can take to fuel your fasted cardio exercise without breaking your fast.

Formula Analysis

  • C8/C10 MCT Oil from 100% Organic Coconuts, 2 g
    • C8 – Caprylic Acid,1 g
    • C10 – Capric Acid,1 g

Performance Lab® MCT is a state-of-the-art MCT oil supplement that delivers clean, pure, triple-filtered C8 and C10 MCTs at a 60:40 ratio, respectively.

Of the four MCTs (C6, C8, C10, and C12), only two truly matter when it comes to enhancing athletic performance: C8 (caprylic acid) and C10 (capric acid). With C8 + C10 MCT oil sourced from 100% organic coconuts, Performance Lab® MCT benefits fasted cardio by promoting:

  • Fast-acting, long-lasting fuel for cognitive and metabolic performance
  • Brain cell mitochondria production, protection, and efficiency
  • Mind-body vitality during high-intensity exercise and fasted cardio
  • Fat loss results for intermittent fasting and ketogenic dieting programs

Although MCT oil does not directly promote anabolic muscle growth, taking an MCT oil supplement prior to exercising on an empty stomach may help encourage the body to use ketones, a brain energy fuel sourced from fat, to fuel athletic performance.

By bolstering the brain’s defenses against fasting-related fatigue, Performance Lab® MCT can help sustain cognitive energy and intensity during fasted training.

Exercise endurance is key to a successful workout. And as one study from 2018 observed, MCT oil supplementation may help enhance exercise endurance by increasing mitochondrial biogenesis and function. Research findings on MCT supplementation indicates “a beneficial effect of dietary MCT in exercise performance through the increase of mitochondrial biogenesis and metabolism.”

Taken daily and consistently with (or without) an intermittent fasting regimen, Performance Lab® MCT can help you maximize your fasted cardio results by combating the low-energy effects associated with fasting.

Get the Best Deal on Performance Lab® MCT Here

Conclusion

You fast to burn fat and recalibrate your metabolism. You exercise to build muscle and kick your metabolism into high gear. These aren’t exactly tit-for-tat compatible goals.

However, with perfect timing and a nutrient-dense diet, burning fat and building muscle isn’t so much easy as it is simply doable.

And you can do it.

But you can easily do it with Burn Lab Pro® and the Performance Lab® SPORT Range of supplements.

Performance Lab® SPORT can help you maximize your fasted cardio benefits while minimizing the downsides of fasting, allowing you to burn more fat and build more muscle in less time.

There are few things worse than spending a significant amount of time and effort at the gym every week to only feel like you’re still not amounting to the best version of yourself that you can—and should—be. And it’s an especially hopeless feeling when you literally can’t spend any more time nor effort, due to your other obligations to your job, your friends, your family.

This is why taking a performance stack, such as Burn Lab Pro® +  Performance Lab® MCT, is such a smart move when it comes to sustaining a healthy, active, and, most importantly, effective lifestyle routine.

Certainly, if you’re going through the troubles and discomforts involved with intermittent fasting and exercising on an empty stomach, you’ll want to see some results—more specifically, you’ll want to see some cut abs on a rock-hard bod.

And that’s exactly what you’ll get with Performance Lab® and Burn Lab Pro®.

  • Get the Best Deal on Burn Lab Pro® Here.

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