If you’re an athlete or someone who works out intensely on a regular basis, then you know the importance of pre-workout.
Many people use pre-workout to increase endurance and focus during a workout, whether it’s lifting weights or playing a sport like basketball.
Pre-workout may also be helpful in fat loss if your workouts are particularly intense or last more than an hour.
However, if you’re trying to lose weight through intermittent fasting, then you might wonder if you can use pre-workout while intermittent fasting?
What Is Pre-Workout?
Pre-workout supplements are designed to boost your energy and focus so you can push your body harder during workouts.
The most popular ingredients in pre-workouts include caffeine, BCAAs, creatine, beta-alanine, arginine, and more.
Pre-workouts generally come in powders or capsules; some pre-workouts also include gummies or chews.
Each product is designed to work differently—not all products will have caffeine for example—so read labels carefully before choosing one.
As mentioned above, pre-workouts typically contain stimulants like caffeine.
What Is Intermittent Fasting?
Intermittent fasting is a way of eating that limits your daily calorie intake.
It isn’t a diet, but rather an intermittent method of keeping calories low on certain days. The most popular types are:
- The 16/8 Method, which consists of skipping breakfast and eating dinner by 8 p.m.
- The 5:2 Method, in which you consume fewer than 500 calories for two non-consecutive days per week.
- No Calorie Diet, or zero-calorie fasting where you consume no food for 24 hours.
- Alternate Day Fasting (ADF), which requires you to fast every other day.
- Time-Restricted Feeding (TRF), in which you eat within an eight-hour window each day.
One important point about Intermittent fasting is that it doesn’t mean you should go days without eating.
As with any dietary program, it’s important to consult with your doctor first, as well as consider other aspects of your life—such as if intermittent fasting works with your exercise schedule.
Does Pre-Workout Break Intermittent Fasting?
There are many people who swear by intermittent fasting ( and pre-workout and are unsure about whether or not they should take their pre-workout.
Some will tell you that it’s okay, while others will tell you that it’s a no-go and could ruin your fast.
This can leave some people feeling anxious because they really want to get their pre-workout in but don’t want to ruin a possible chance at seeing results from Intermittent fasting.
The truth is that it really depends on what kind of Intermittent fasting you’re doing, as well as when and how much of your pre-workout is taken.
It also makes a difference if you take it right before or right after your workout!
Ingredients That Disrupt Fasting
Many pre-workout supplements contain a variety of ingredients, but they tend to share a few common traits.
Common ingredients found in pre-workout formulas include beta-alanine, creatine, arginine AKG, and citrulline.
These commonly used performance-enhancing agents each have the potential to disrupt your fast in one way or another.
Sugars
A pre-workout can contain various types of sugar, including sucrose, glucose, fructose, dextrose, and maltodextrin.
In order to break a fast and maximize your insulin sensitivity, it’s recommended to avoid consuming sugary foods or beverages for several hours before beginning a fast.
The sugars in pre-workout drinks will decrease insulin sensitivity by raising blood sugar levels which will reduce fat-burning potential during your fast.
Whey Protein
Pre-workout Whey Protein shakes, even those with just 20 grams of protein, can throw off your fast.
If your fast is 24 hours or longer and you’re drinking a pre-workout that has whey protein in it (or other animal proteins), then you should break your fast prior to exercising on that day.
Amino Acids
Studies show that, for most people, consuming amino acids pre-workout will break a fast and reset your body’s metabolic state.
However, if you’re doing a longer fast (16 hours or more), your body should be in an anabolic state by then.
What does that mean?
That means your body’s primary goal is to repair muscle tissue (as well as help keep you from feeling famished) during fasting periods—which is why it might make sense to take your pre-workout in conjunction with a short pre-breakfast workout.
Fast or not, if you wanna get the BCAAs that I’m taking for the best results. Look no further!
NutraKey BCAA

Ingredients That Won’t Break A Fast
Taking pre-workout before you break your fast will likely throw off your body’s fluid and electrolyte balance, causing you to feel weak and fatigued.
Many pre-workouts contain high levels of caffeine that are designed to give you a boost of energy.
That caffeine will most likely keep you up at night, disrupt your sleep schedule, and make it hard for you to wake up in time for morning prayers.
There is also one important thing to note:
If you take anything besides water while breaking a fast, it is considered breaking your fast—even if it is just a little bit.
This means that taking any form of pills or powders can count as breaking your fast, even if they don’t have calories or sugar in them.
Caffeine

First and foremost, caffeine is a stimulant, which means it will make you feel energized.
If you drink coffee or use pre-workout supplements, you might even think that you’re breaking your fast.
The problem with caffeine is that it doesn’t trigger hormonal changes that turn off hunger signals, like eating food does.
That means caffeine can actually increase appetite, rather than suppress it.
Caffeine also affects blood sugar levels—meaning your insulin spikes sharply if you consume a lot of coffee or other caffeinated products during a fasted state.
All of these side effects make caffeine less than ideal for intermittent fasting purposes.
Relate Post: Can I Use Coffee As A Pre Workout
Creatine
In theory, creatine could break a fast.
The whole reason it’s popular among athletes is that it helps you build muscle by providing your body with energy—more precisely, adenosine triphosphate (ATP).
Your body uses ATP for all sorts of functions in addition to exercise performance, including breathing and converting food into glucose.
But creatine doesn’t contribute directly to ATP production; instead, it produces a byproduct called phosphocreatine.
And phosphocreatine does not provide an alternative energy source for anything besides exercise performance.
Related Post: Glutamine Vs Creatine – Learn All Of The Differences And Benefits
Beta-Alanine
First, let’s talk about beta-alanine.
Beta-alanine is a precursor to carnosine, which has been shown to aid in muscle recovery.
The problem here is that beta-alanine (and thus, carnosine) isn’t synthesized in your body until you begin eating protein again after a fast—meaning you can’t benefit from beta-alanine supplementation while fasting.
Bottom line: pre-workout won’t break your fast and there’s nothing wrong with using it Intermittent fasting you’ve had something to eat recently.
Citrulline Malate
Some people might argue that citrulline malate does not break a fast, but you’d be hard-pressed to find anything on PubMed about its effects in humans.
However, when you look at studies in rats (the next best thing), there is evidence that citrulline malate reduces fasting-induced glucose intolerance and improves insulin sensitivity.
The results of another study also showed that citrulline malate can lower blood pressure and reduce oxidative stress.
Still, because there have been no human studies conducted specifically with intermittent fasting and citrulline malate, we have no way of knowing whether it will have any effect.
Until then, it’s probably better to stay away from pre-workout supplements while fasting.
The Best Pre-Workouts For Intermittent Fasting
In my opinion this is the best Pre-Workout to go with that won’t affect your fast! This is you best choice for not breaking your fast.
If this doesn’t get you fired up for a workout I don’t know what will.
Cellucor C4

What Should I Drink Before Fasting And Working Out?
A fasted workout should mean you are going to be doing it first thing in the morning or after not eating anything for at least 12 hours before your workout.
So, as long as you have gone a full 12 hours without eating or drinking any calories, you can drink water and black coffee (no sugar or creamer).
Coffee is a diuretic, which means it will make you pee more than water would, but that doesn’t necessarily mean you are getting rid of more electrolytes or hydration.
On top of that, coffee contains caffeine, so if weight loss is your goal you may want to opt for water instead.
Related Post: What Supplements Should I Take When Working Out?
Can You Take BCAA While Fasting?
The BCAA leucine, isoleucine, and valine are known as essential amino acids because your body cannot produce them, meaning you must consume them through diet or supplementation.
Your body uses these essential amino acids to support a variety of functions, including immune function and protein synthesis.
Consuming protein around your workout may actually help you build more muscle as well.
However, it’s unclear whether or not taking BCAA during a fast will break your fast.
One study published in Metabolism suggests that while BCAAs don’t break a fast on their own, if they have another protein source in addition to BCAAs during fasting, then it may be able to break your fasted state.
Does Pre-Workout Spike Insulin?
When you eat a meal, insulin is released to drive nutrients into cells.
If you’re doing intermittent fasting, a pre-workout snack or shake might temporarily spike insulin levels, which can result in fat storage because your body doesn’t yet have an opportunity to burn all those incoming calories.
That said, if you wait long enough—usually around four hours after eating—your body will start burning fat as its primary fuel source again.
In that case, it’s totally fine to use pre-workout before breaking your fast because your body is already in a state of ketosis and ready for action.
Some research suggests pre-workouts may even help with ketone production, but more studies are needed on that front.
How Long Does It Take For 16 8 Intermittent Fasting To Work?
One question we get frequently from many of our visitors is, How long does it take for 16 8 intermittent fasting to work?
This is a question that depends on a few different factors.
Not all people respond to changes in their diet at the same rate and some will see results much faster than others.
Those who are younger or have never been overweight tend to lose weight quickly and will see noticeable results faster than those who are older or have been overweight for many years.
The next thing to consider is how much weight you need to lose.
If you are 100 pounds overweight, then obviously you will notice your clothes fitting differently sooner than someone who only needs to lose 10 pounds.
Related Post: 15 Intermittent Fasting Do’s And Don’ts
Final Mop Up
Pre-Workout can be used while intermittent fasting but you just need to read the packets and make sure there’s no ingredients that’ll break you fast.
But save yourself the hassle, grab the pre-workout I use and you’ll know you’re safe!