The goal of this article is to make intermittent fasting and morning workouts simple. We’ll discuss the science both for and against fasted workouts to help you make an educated plan.
I’ll explain as fast as I can. Let’s HIIT it!
intermittent fasting and morning workouts
A lot of people think they can’t do intermittent fasting if they work out in the morning. Others are scared that they shouldn’t because they’ll risk losing hard-earned muscle.
Both concerns are valid but not 100% true.
Intermittent fasting is flexible. You can shift your eating window until you find what works best for your morning workout and schedule.
What’s more, a growing number of data shows that morning workouts and intermittent fasting will not jeopardize muscle mass. Our experience corroborates that.
We have been researching and self-experimenting with fasting since 2018. The goal of this article is to make intermittent fasting and morning workouts more straightforward by tackling your concerns head-on.
For additional well-researched content backed by personal experience, check out the articles on our fasting page.
So, first things first, let’s talk about the number one myth regarding intermittent fasting and working out.
The Biggest Myth About Working Out and Fasting
Myth: If you don’t fuel with food or supplementation before or after your workout you will lose muscle mass.
You see these claims all over the web, coming from huge names in the health and fitness industry. Here are some examples:
“It is true that you may lose more fat working out fasted; however, you may also lose more muscle. If the body’s glycogen stores (aka energy stores) are depleted, the body can break down protein for fuel—the opposite of what most people are looking for.” – Quote from a mindbodygreen article
“While fasted lifting is a big fat mistake, fasted cardio is fine and may help you burn additional fat. You won’t gain much muscle if you’re fasting. So for best results, schedule those lifting sessions during or after your feeding windows, and schedule cardio before them.” – Quote from a Men’s Health article
“If you do heavy lifting, it’s important for your body to have protein after the workout to aid with regeneration. Follow up any strength training with carbohydrates and about 20 grams of protein within 30 minutes after your workout.” – Quote from a Healthline article
I classify this as a myth because it’s widely accepted as a fact but there isn’t consistent scientific evidence to back it up.
But, that goes both ways. Meaning, there isn’t enough evidence to show that fasting during your workout is beneficial for muscle growth.
So, since science doesn’t provide all the answers (which is typical with fitness and nutrition), we had to make a judgment call, give it a try, and learn for ourselves.
Here’s what we have learned.
Our Morning Workout and IF Experience
Understandably, you’re worried about losing muscle. Muscle is the best weapon we have to fight weight gain. Additionally, lean muscle is critical to maintaining metabolism as we age.
Our experience and a growing amount of data show that fasting will not cause muscle loss as long as resistance training and caloric goals are maintained.
Ever the engineers, we dive into science and research when trying to optimize our health and vitality. But in this case, the science isn’t there yet. Therefore, our opinion on intermittent fasting and morning workouts is formed by our experience.
In 2011, I first tried a morning HIIT cardio program called Max T3. The trainers suggested fasting for two hours after each workout. My results were shocking at the time, and still memorable enough to be talking about nearly a decade later.
I quickly lost 5 pounds in the first 2 weeks. And the only change I made was doing the short workouts (12 minutes each and only 3 days a week) and fasting for two hours after.
In 2018, Alex and I started doing fasted workouts when we began following a 16/8 (16 hours of fasting and 8 hours of feeding) intermittent fasting plan. We tracked how we felt and our fitness progress, and because of our results, we haven’t changed a thing since.
We even tried fasted hiking recently while hiking the Appalachian Trail and we seemed to cover more miles.
We experimented with working out in the morning, afternoon, and evening while intermittent fasting, and even though working out on an empty stomach was scary at first, morning workouts in a fasted state proved ideal for our results and schedule.
Based on our results, you can work out while fasting without losing any muscle. What’s more, you can gain muscle more efficiently if you do so.
Why fasting and morning workouts work
First, let’s discuss how intermittent fasting for muscle gain works.
As described in our article titled, “The Health Benefits of Intermittent Fasting,” after a meal, excess glucose from the blood is stored in the liver, muscles, and fat cells.
Here’s Why You Won’t Lose Muscle
So, how does the body know not to burn muscle?
First, there’s more HGH
The reason for this is due to human growth hormone (HGH). Human growth hormone is vital in muscle growth, body composition, cell repair, and metabolism.
It grows muscles, increases strength, and all while reducing recovery time. For this reason, the Olympics banned it as an illegal substance and steroid in athletes in 1989.
Produced naturally by the pituitary gland, many studies have shown that fasting drastically increases the production of human growth hormone. Research cites an increase between 100%-2000% over 24 hours of fasting.
During fasting, human growth hormone levels can more than double, which preserves muscle and strength.
A word of warning: while fasting, it is still essential to consume enough calories and exercise with strength training. Like any weight-loss diet, small amounts of lean mass (including muscle) are lost along with the fat mass.
The good news is that studies have shown that muscle mass can be maintained or grown as long as you perform proper strength and resistance training.
If not, you’re at risk of losing 1-2 lbs. of muscle mass over a few months, which would likely be the case whether or not you’re following an intermittent fasting plan.
In short, our bodies are smart enough to know that fat burns before muscle.
Then, there are 24 hours of protein synthesis
Here’s another reason why you won’t lose muscle.
Muscles don’t grow and recover in an hour after exercise. Instead, it takes them a day or longer to recover. Protein synthesis is the process of rebuilding the muscles broken down during exercise and helping them recover stronger.
This study shows that the rate of protein synthesis gradually builds and peaks 24 hours after a resistance workout.
That means that as long as we fuel our body with quality carbs and protein during the 24 hours after a workout, we are still supporting muscle growth and recovery.
Actually, if protein synthesis increases steadily after a workout, it would make sense to continue fasting after a workout. By doing this, you’ll maximize muscle growth and recovery by breaking your fast when protein synthesis is closer to its peak.
While this is just one study, I’m confident that fasted workouts have helped me gain muscle mass more efficiently while maintaining a more trim waistline.
Which leads me to another good reason to try intermittent fasting with morning workouts.
Here’s Why You Will Lose Weight
While it’s not widely accepted or scientifically proven that fasted workouts are good for muscle gain, it is for fat loss. This is for a couple of reasons.
It’s stored fat or bust
Simply put, when you’re in a fasted state your body can’t burn glycogen (stored carbs), so it has to burn stored fat.
But that’s only if you’ve been in a fasted state long enough to deplete the glucose and insulin in your bloodstream. At that point, a metabolic shift occurs to start burning the glucose stored in fat for energy.
Depending on your diet, insulin sensitivity, and exercise level, “long enough” is somewhere between 12-36 hours.
If you maintain a poor diet, a 16/8 intermittent fasting schedule may not be long enough for you to realize a positive metabolic impact. That is why it’s crucial to have a well-balanced diet full of vegetables, beans, and legumes.
Are morning workouts and if best?
Now that you know intermittent fasting and morning workouts won’t destroy your muscle mass, implementing a plan is easy.
You don’t have to worry about timing your meals around your workout to maximize results.
Instead, you can focus on doing your morning workout, breaking your fast when it makes sense for you (ideally 1-3 hours after working out), and eating healthy meals throughout the day.
So, are morning workouts and intermittent fasting the best route for your optimal health? There’s only one way to find out.
What To Expect
Think of intermittent fasting with morning workouts as a tool in your healthy living toolbox. To properly use that tool, you need to try it and understand how it helps you get the job done.
If it helps, incorporate it into your routine while still utilizing other effective healthy living tools. But, if it doesn’t work — meaning you can’t do it without feeling weak, slow, or dizzy — that’s fine. There are many other ways to live a healthy lifestyle.
You don’t have to work out in the morning or in a fasted state to get the benefits of intermittent fasting. And, you don’t have to intermittent fast to realize the benefits of morning workouts.
There are cases where people don’t like morning workouts and intermittent fasting. It’s especially challenging if your schedule only allows very early morning workouts.
Working out at 6 AM and then not being able to break your fast until 11 AM is challenging, especially after a high-intensity workout. That can be a deal-breaker.
Also, while there are bodybuilders who are intermittent fasters, from my limited experience, it might not be the best plan if you have bodybuilding competition goals.
Be Patient and Monitor Progress
As always, you need to pay close attention to your body’s response to a diet or exercise change. But, you also need to be patient. Don’t expect it to take days or weeks. It will take months.
Just like intermittent fasting is hard at first, so are fasted workouts. It takes time to break through that barrier.
To understand if you are making progress, pay attention to your workout performance and how you feel throughout the day. Then, you need to track your progress with a body measurement chart.
As engineers, we always say, “What’s measured gets improved.” How can you know if you are gaining or losing muscle if you aren’t tracking your body measurements?
Tracking progress properly involves taking body measurements, photos, weight on the scale, and measuring body fat percentage.
If you’re really serious about optimizing your workouts and the health benefits of fasting, you need to look at the Lumen metabolism tracker. It’s a recent discovery of ours and a complete game-changer. We talk all about our experience and results (that came incredibly easy) in our full review of Lumen.
INtermittent Fasting and Morning Workout Tips
When you start, measuring your progress as described above, and following these tips, you should feel stronger and more athletic, not weaker.
Follow Rule #1: Eat enough
Many people on IF plans lose weight because it’s harder to overeat in a shorter time window. But, under-eating is just as problematic, especially if you are trying to maximize your results from a workout plan.
Track your calories and make sure you’re eating enough. We share how to calculate and track your calories in our 30-Day Weight Loss Challenge.
Follow Rule #2: Hydrate like crazy
Just because you’re not eating, doesn’t mean you’re not drinking water. Do not let fasting cause dehydration. Start your day with a big glass of water and carry a full water bottle with you as a reminder.
Drink at least one-half of your body weight in ounces. For example, an individual who weighs 200 pounds should drink at least 100 ounces or three full Nalgene bottles.
If you want to keep it really simple and avoid math, just try drinking a gallon of water a day and see how you feel.
Ease into it and optimize
Be patient during your transition. You’ll likely find that on moderate to high-intensity workout days you want to eat right after.
If you can’t resist the hunger, have a banana and peanut butter. If it doesn’t get easier, move your workouts closer to the start of your eating window.
When you start, it might feel like you have no energy in the morning. If after one month, this doesn’t improve, try eating more carbs at night to get your glycogen levels higher.
You be the judge
If you listen to your body, follow these tips, review our intermittent fasting how-to guide, and still feel like crap, call it quits.
Morning Workouts and Other Fasting Plans
We only recommend the typical 16/8 intermittent fasting plan. We like this because it’s consistent and simplifies our daily routine.
We don’t recommend the 5/2 (5 days of normal eating and 2 days of restricted eating per week) intermittent fasting plan. It seems more difficult to implement and there are no clear benefits over the 16/8 plan.
If we did follow a 5/2 plan, our strategy would be to take our rest days on the 2 days of restricted eating (typically around 500 calories). Since you’re eating fewer calories that day, there is no need to burn more calories.
Regarding extended fasting, we have only done a 3-day fast. We worked out on the first day, and then did yoga or went for a walk on the remaining days in addition to some intense yard throughout during a hot summer week.
You shouldn’t be worried about working out on an extended fast. You should be fasting under medical supervision if you fast any longer than 3-5 days.
Recommended Morning Workouts
At Ryan and Alex Duo Life, we have created two highly effective, free programs with over 4,000 users currently.
Both of them are 8-week programs with workouts three days a week. Don’t worry, when you work out your full body with proper intensity, you only need to work out three times a week.
First, Some Freebies
Take a look at our free programs optimized for weight loss and strength building:
Second, A Cheap Option
Early in the post, I mentioned a morning workout plan called Max T3. These are incredibly short workouts (12 minutes) that are high-intensity with zero rest. You can buy them for $19.99 at maxt3.com.
Outside of the workouts on BODi, these are the most practical and effective workouts I have ever experienced. You’ll achieve great results in a fraction of the time by utilizing metabolic conditioning.
According to MaxLiving, the company behind the Max T3 program, metabolic conditioning consists of short bursts of high-intensity exercise. This type of exercise takes much less time and stimulates processes in your body that continue to burn fat for up to 48 hours after your workout!
I followed this program in 2011 and I tracked solid results. The workouts are intense, which is exactly why they work.
Lastly, The Best Option
BODi is hands-down the best workout platform available.
I won’t rant about it here because we already wrote a data-driven review of BODi. If you’re serious about getting into an at-home exercise routine, it’s a no-brainer.
If you already have Beachbody On Demand, commit to one of these top Beachbody workout programs to get the best results.
Closing Thoughts on Intermittent fasting Workouts
We hope this article has helped you work out while fasting. It’s an extremely effective plan for fat loss.
Leave any specific questions about intermittent fasting and working out in the comments below. We prefer that to email because the discussion helps all future readers. Thanks!
For general questions about fasting, such as why you’re not losing weight on intermittent fasting, head over to our Fasting Page. Or download our Fasting Bundle below.
The Proven Fasting Bundle (Printable PDF Guide)
Read by 143,364 fasters in 2022 alone, the Fasting Bundle is the structure and tools you need to succeed.
- Intermittent and alternate-day fasting meal plans
- Checklist for before, during, and after a prolonged fast
- Benefits, challenges, and a beginners how-to guide
Plus, we're just an email away for support.
30-Day Weight Loss Challenge
As engineers with a combined twelve years of health coaching experience, we needed to create a data-driven way for our clients to sustain weight loss.
Too many weight loss challenges involve a long list of what you can, cannot, and need to do every day. We’ve reduced the overwhelm and only require you to track five numbers a day — calories, steps, fiber, sleep, and waistline.
You’ll track five numbers daily to give you the highest return for sustainable weight loss. As a bonus, we’ll share our Weight Loss Bundle, which includes strategies, progress tracking tools, and additional weight loss plans.
Hey we're Ryan and Alex
The creators of Ryan and Alex Duo Life. We are a husband-wife duo and “lifestyle engineers.”
After eight years working in the corporate world as engineers, we left our high-powered jobs to tackle our true passion — helping couples engineer their best lives.
The synergy of our engineering minds and ten years of health coaching experience produced Ryan and Alex Duo Life. Our mission is to help you transform your bodies, minds, and relationship as a couple.
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