Have you ever wondered why you can feel so different in your workouts depending on the day?
Some days you feel like you can do anything, but others you feel like you can’t push as hard? The secret might just lie inside your muscles.
More specifically, I’m talking about your glycogen stores. When these stores are low, you’re going to feel like you don’t have as much effort to give.
You see, glycogen is the fuel that powers your muscles during intense exercise. This includes everything from lifting weights to running a mile.
It’s the energy reserve we carry to give us short bursts of energy when we really need it. It actually can last a while, but this depends on the intensity of your workout.
Why do we need glycogen, though? Is it just to help us lift more weight?
Well, look at it through a lens of survival. Our bodies are the ultimate survival machines, and are constantly adapting to make sure we do.
In the case of survival, glycogen could serve as the energy your body needs to fight or run. Now, this doesn't happen anywhere near as often as it did thousands of years ago ... But, you never know when you'll need the energy to act!
That's why we still have glycogen, which we can now use to our advantage. For one, making sure we have plenty of it can support higher performance in fitness. During high intensity workouts and resistance training, glycogen is the body's main source of fuel.
This also means you can deplete glycogen quite a bit during these workouts. That's why it can be pretty important to replenish this energy after you train.
It not only helps with recovery, but also prepares you for your next workout. So, if you want to learn the right way to replenish this energy, you’ve come to the right place.
I’m not just going to teach you how to replenish your glycogen stores, though. I’m also going to walk you through how to increase glycogen stores to help you store even more energy over time!
This could help take your training and performance to a new level! Let's dive into the science of muscle glycogen and how to increase glycogen stores in muscle.
What is Glycogen?
Let’s start with a metaphor to give you an idea of what glycogen is.
If your body was an engine running solely on body fat it would be a 4 cylinder engine. Lower power capabilities, but very fuel efficient.
If you were an engine running on carbohydrates, you’d be a V8 engine with much more power. It’s not quite as fuel efficient, but you could work much harder and faster.
Glycogen is just a form of stored carbohydrate in your muscle tissue. It’s also stored in your liver, but our main focus today will be on muscle glycogen.
When your muscles need energy quickly, this is the energy they go for. Think of it like a backup battery that kicks in when you start to push yourself.
By “push yourself,” I don’t just mean doing all out sprints. Anything from jogging to lifting weights falls under that umbrella too. Think resistance workouts or high-intensity workouts.
So, how does glycogen work to give us energy?
Glycogen is made up of glucose molecules linked together in branches. Glucose is the simplest type of sugar in your body.
It’s quickly and easily used for energy, which is why it’s what makes up our blood sugar.
When your muscles demand energy, branches of glycogen are broken down into glucose. This gives a quick and sustainable source of energy that powers your muscles.
That’s muscle glycogen. But, remember how I said your liver has glycogen too? What’s that for?
Well, liver glycogen is more important for keeping your blood sugar levels stable. This is necessary when you're not eating, like overnight or between meals.
If your blood sugar starts getting low, your liver breaks down glycogen to bring it back into balance.
This isn’t just when you’re active, but also when you’re dreaming. Your brain uses glucose for energy, and this can deplete your blood sugar too.
So, understanding how to regulate glycogen can help with more than just your workouts.
When it does come to our workouts, though, how much glycogen do we have in our muscles?
How Much Glycogen is Stored in Your Muscles?
When it comes to glycogen, not everyone is packing the same amount in their muscles. After all, we don’t all have the same amount of muscle tissue in the first place.
Think of muscle like the gas tank in different cars. Some are larger and can hold more fuel, giving them a longer range before the next fill-up.
Several factors influence how much glycogen your muscles can store. The more you have though, the longer and more intensely you can train. So, what are these factors?
Body Composition
This is pretty straightforward. The more muscle mass you have, the more room there is to store glycogen. Just like having a bigger gas tank means you can hold more fuel, more muscle means more space for glycogen.
Type of Exercise
Not all forms of exercise are created equal. This is especially true in the glycogen demand department. Endurance sports like marathon running can deplete glycogen differently than weight lifting.
The amount of time exercising determines this as well. You might run a marathon in 3 hours, but you likely aren’t in the gym for that long. You are, however, exercising with more intensity when you lift weights.
So, the intensity and exercise duration both make a difference.
Fitness Level
Here’s where training consistently can really pay off. When you are just starting out, you likely don’t have the maximum amount of glycogen you can hold. You haven’t needed it before, so your body likely hasn't stored as much.
The more trained you become, the more glycogen you can begin to hold. As you build more muscle, you’ll hold even more as well. Think of it like your gas tank growing bigger the more you drive your car. Pretty cool, right?!
Diet
What you eat matters too. Diets rich in carbohydrates act like frequent top-offs for your glycogen levels. It would be like stopping for gas multiple times a day to make sure you always have a full tank.
On the other hand, if you're on a low-carb diet, your glycogen stores may not be fully stocked. This can make those long workouts or intense sessions a bit tougher to get through.
According to ACSM, an average man holds roughly 500 grams of muscle glycogen (1). Based on what we just talked about though, that’s a little overgeneralized.
That statistic is based on a 70 kg (154 lbs) man with 40% of his weight being muscle mass, which is 28 kg (61.6 lbs). Someone with more muscle mass than that could likely hold more glycogen.
That would come out to about 8.1 grams of glycogen per pound of muscle.
For example, I am about 200 pounds, and according to my last assessment, I have about 106 pounds of muscle. At that same concentration, I would hold about 860 grams of muscle glycogen.
Now, that’s just an educated guess. It does, however, show that how much glycogen we store can vary.
Understanding how much glycogen your muscles can store can help you adjust your diet accordingly. If you can store a lot more glycogen, a diet higher in carbohydrates could help you fill those stores (2).
It’s all about setting yourself up for success so you can perform at your best. So, let's take a closer look at how to increase glycogen stores in muscle.
How to Increase Glycogen Stores in Muscle
If you want to amp up your workout performance, glycogen replenishment is key. Doing it the right way, though, can be important.
More specifically, we want to increase glycogen stores in the muscle. Sure, liver glycogen matters too. But when it comes to performance, we’re looking at your muscles.
How you fuel your body can make a big difference in how much glycogen you have going into your workouts. First though, you need to give your body a reason to overfill its glycogen stores. This just means you have to deplete them a lot.
This can be achieved with 40-90 minutes of high intensity exercise (4). I mean HIGH intensity exercise!
Some studies say 2 hours or more of moderate intensity exercise will deplete glycogen as well (2). It really depends on the type of training and how hard they were training in those studies.
When your glycogen stores are depleted, you’ll feel exhausted and very low on energy. I’ve done this, and my arms and legs felt almost too heavy to move.
Once that is achieved, then you need to take these strategies into account.
Choosing the Right Carbs For Your Meals
Not all carbs fill your glycogen levels the same way. Yes, if you eat enough carbs, eventually you will refill your glycogen stores.
...But the speed at which they refill will vary depending on the glycemic index of the carbs you eat.
Within 24 hours after exercise, this is what studies show. High glycemic carbs replenished more glycogen than low glycemic carbs (3).
This could be due to the speed they were replenished, but both groups ate the same total amount of carbs. So, when it comes to replenishing glycogen as fast as possible, high glycemic carbs are the better choice.
What are high glycemic (GI) carbs though?
High GI carbs digest faster, and tend to have more sugars. Low GI carbs are more complex and digest much slower.
Now, I’m not saying you should just load up on sugar and processed garbage in your meals. The purpose of getting high GI carbs to replenish glycogen needs to be strategic.
There’s a difference between choosing candy for your high GI carbs vs nutrient dense foods. Yes, there are nutrient dense high GI carb sources out there. These are the more optimal choices when it comes to your meals.
When going for high GI carbs in meals, aim for whole foods that also provide other healthy nutrients. That way you have some fiber, vitamins, and minerals to go along with it.
Here are some higher GI carb sources I recommend:
• White rice
• Baked potato
• Watermelon
• Raisins
• Orange juice
• Bagels
• White bread
• Instant oatmeal
These carbs break down quicker, and start pumping glycogen back into your muscles sooner. This is especially important when you have another big workout within 24 hours of the one you just had.
On days you aren’t working out, and may not work out the next day, I would stick to lower GI carbs for your meals. They’ll still help you replenish glycogen, but they won’t do it as quickly.
If you don’t need glycogen replenished for 48 hours or more, you don’t need as many high GI carbs.
Supplements For Glycogen Replenishment
So you want to know how to replenish glycogen stores in muscle? Starting right after your workout is a great idea! It can also be a super ideal time to consume higher glycemic carbohydrates.
I already mentioned that glycogen is made of branches of glucose, right? Glucose is actually what your body breaks all carbs down to. So, if you were looking for the quickest way to replenish glycogen ... Wouldn't it be with glucose?
I would argue yes. In fact, I've been taking glucose powder after my workouts for over 12 years! I tell you what ... It has made a huge difference in my training, results, and even recovery.
There’s also a large benefit to taking protein with your glucose. Studies show the protein and carbohydrate combo can increase glycogen replenishment rates (5).
That's why I recommend taking a fast digesting protein like whey protein isolate with it. It will help kickstart the repair process, and taking both is even better for muscle recovery (5).
So, if you want to increase glycogen stores in muscle, start with the right post workout shake. Whey protein isolate and glucose is the way to go!
How Many Carbohydrates Do You Need to Replenish Glycogen?
The amount of carbohydrates you need to replenish glycogen depends. It depends on factors like:
• How much muscle you have
• How much intensity you train with
• How long you trained at that intensity
This is what the research suggests. After glycogen depleting exercise, 6-12 grams of carbs per kilogram of body weight will refill those stores (6).
That can be a hefty amount though. For me, that would be between 545-1091 grams of carbs.
I don’t think most people are depleting their glycogen stores enough that they’d need that much. That’s more so if you completely depleted it from all the muscles in your body.
If you just ran a marathon at a fast pace, then you probably depleted most of your glycogen. If that’s you, then that may be how much you'll need.
These studies were done on elite endurance athletes training A LOT. So, for the average person reading this, those numbers are a little higher than I’d recommend.
Another study found after exhaustive exercise that 1 g/kg carbs per hour for 5 hours did the trick (7).
If you are really exhausting yourself in your workout, that’s more realistic. For me, that would be 455 g carbs for that day.
If you just had a typical gym session, you likely will refill your glycogen stores before you hit that amount. You could try to shoot for half of that amount and see if your next workout feels good enough.
Also, take into account that those recommendations are based on total body weight. If you have a very low body fat percentage, those numbers are more accurate for you.
If you have a higher body fat percentage, less of your body weight is muscle. If that’s you, then you may want to adjust the numbers down a bit too.
Start Increasing Glycogen Stores The Right Way
From athletes to gym goers, glycogen storage really is key to optimal performance. It’s your gas tank for intense exercise!
When your glycogen stores are full, your endurance, strength, and speed can be maximized. This allows you to push harder and achieve more in your fitness journey.
In order to increase the amount of glycogen you store, remember these things:
1. You have to work out hard enough, and long enough, to heavily deplete your glycogen levels. You’ll probably feel like you want to lay on the floor for a while after.
• 90 minutes of high intensity exercise
• 2+ hours of moderately high intensity exercise
2. Take a post workout recovery shake.
• Whey protein isolate and glucose
3. You have to eat a lot of carbohydrates.
• 5-6 g/kg carbohydrates (including post workout shake)
If you’re just going to the gym regularly and want to perform well, you don’t need to follow that. Just make sure you’re taking your post workout shake, and shoot for 2.5-3+ g/kg carbs that day.
That will likely be enough, but if you feel like you need more … Try more! You can always make adjustments to see what works best for you!
Like I said, everyone is different. There’s no perfect number for every single person.
Regardless, something I always recommend is a post workout shake. Now, I understand it can be hard to know where to look and what to look for. There are a lot of supplements out there, and not all of them are of the best quality.
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That's why I'm confident in saying our Post Workout Stack is an excellent choice for your recovery and glycogen replenishment. It's the same stack I've been taking all these years, and I couldn't imagine a workout without it.
The Post Workout Stack is a combination of our whey protein isolate (Phormula-1) and post-workout glucose (Ignition).
It's a stack that can help replenish glycogen, support muscle growth, and reduce soreness! Trust me - It also tastes better than ANY other protein shake you’ll ever try. You don't have to take my word for it though ... Just take a look at the reviews. Thousands of people give the Post Workout Stack 5 out of 5 stars!
So, if you're looking for a great way to take your results to the next level and start replenishing glycogen more effectively after your workouts ... You can try out the Post Workout Stack for yourself here!
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References:
(1) American College of Sports Medicine. (2006). ACSM's advanced exercise physiology (Vol. 143). Lippincott Williams & Wilkins.
(2) Murray B, Rosenbloom C. Fundamentals of glycogen metabolism for coaches and athletes. Nutr Rev. 2018 Apr 1;76(4):243-259. doi: 10.1093/nutrit/nuy001. PMID: 29444266; PMCID: PMC6019055.
(3) Burke LM, Collier GR, Hargreaves M. Muscle glycogen storage after prolonged exercise: effect of the glycemic index of carbohydrate feedings. J Appl Physiol (1985). 1993 Aug;75(2):1019-23. doi: 10.1152/jappl.1993.75.2.1019. PMID: 8226443.
(4) Gonzalez JT, Fuchs CJ, Betts JA, van Loon LJ. Glucose Plus Fructose Ingestion for Post-Exercise Recovery-Greater than the Sum of Its Parts? Nutrients. 2017 Mar 30;9(4):344. doi: 10.3390/nu9040344. PMID: 28358334; PMCID: PMC5409683.
(5) Margolis LM, Allen JT, Hatch-McChesney A, Pasiakos SM. Coingestion of Carbohydrate and Protein on Muscle Glycogen Synthesis after Exercise: A Meta-analysis. Med Sci Sports Exerc. 2021 Feb 1;53(2):384-393. doi: 10.1249/MSS.0000000000002476. PMID: 32826640; PMCID: PMC7803445.
(6) Alghannam AF, Gonzalez JT, Betts JA. Restoration of Muscle Glycogen and Functional Capacity: Role of Post-Exercise Carbohydrate and Protein Co-Ingestion. Nutrients. 2018 Feb 23;10(2):253. doi: 10.3390/nu10020253. PMID: 29473893; PMCID: PMC5852829.
(7) Jentjens R, Jeukendrup A. Determinants of post-exercise glycogen synthesis during short-term recovery. Sports Med. 2003;33(2):117-44. doi: 10.2165/00007256-200333020-00004. PMID: 12617691.
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