Why do some skinny guys have belly fat? If you aren’t overweight, why is fat accumulating, and why is it clustering in your midsection? There are a few reasons this can happen, and five things we can do to fix it, but all of it boils down to one term: nutrient partitioning.
In this article, we’ll explain why you’re gaining belly fat instead of muscle when you gain weight, and why you’re burning muscle instead of fat when you lose it. If you can fix these two things, you’ll gradually become leaner and more muscular instead of skinnier and fatter.
Then, after covering nutrient partitioning, which will gradually get you in shape, we’ll talk about how to turn up the dial so that you can build muscle and burn belly fat much faster.
Why Are You Skinny With Belly Fat?
Let’s imagine that you eat 2,500 calories every day. 2,400 of those calories fuel your body and daily activities, leaving 100 extra calories. Where do those extra calories go? Are they burned off, are they invested into muscle growth, or are they stored as fat? And if those extra calories are stored as fat, are they stored specifically as belly fat?
Now let’s imagine that you eat 2,300 calories every day… but you still burn 2,400 calories as fuel, leaving a deficit of 100 calories. Where are those calories taken from? Does your metabolism slow to cancel out the deficit, are the calories taken from your muscle mass, making you skinnier, or are the calories taken from your fat stores, making you leaner? And if those calories are taken from your body fat, are they taken specifically from your belly fat?
If you have good nutrient partitioning, when you gain weight, you’ll gain mostly muscle. When you lose weight, you’ll lose mostly fat. Over time, you’ll either become more muscular, leaner, or both.
But if you have bad nutrient partitioning, when you gain weight, you’ll gain mostly belly fat. When you lose weight you’ll lose mostly muscle. And over time, you’ll either become skinnier, fatter, or both—skinny fat.
So, how can you improve your nutrient partitioning? How can you make it so that when you lose weight, you lose belly fat? And how can you make it so that when you gain weight, you gain mostly muscle?
How to Improve Nutrient Partitioning
Resistance training is by far the most powerful tool for becoming simultaneously leaner and more muscular. If you aren’t in the habit of lifting weights or an alternative, such as bodyweight training or resistance bands, then we’ve found the reason why you’re skinny with belly fat. You’re skinny because your body has no need for bigger muscles, and you have belly fat because any extra energy you consume is stored as fat instead of muscle. The solution, then, is as simple as it is hard: start lifting weights.
The solution is simple in the sense that you don’t need to overthink it. Hypertrophy training (aka bodybuilding) is best, but most weight training programs will be good enough to stimulate muscle growth. Approach each workout with the goal is lifting more weight or doing more repetitions than last time, and as you progressively outlift yourself, you will gradually build muscle.
The solution is hard in the sense that it’s hard to find the time and energy to overcome the inertia of a sedentary lifestyle. It’s hard to get into the habit of lifting weights, it’s hard to learn a bunch of new lifts, it’s hard to add weight to the bar, and it’s hard to fight for extra reps each workout. If you need to build a home gym or get a gym membership, it might also cost some money that you didn’t plan on spending. But if you have the drive to actually do it, it will work wonders.
For example, in this 12-week study, the researchers split the participants into three groups. The first group wasn’t told to work out, they were just put on a fat-loss diet. Here are their results:
As expected, the calorie deficit did indeed cause them to lose weight, but only 1/3 of the weight loss was muscle. That means they were losing weight with the same 2:1 ratio of fat-to-muscle that people become overweight with in the first place. So by losing weight, they weren’t improving their ratio of fat to muscle, they were just getting smaller. That’s why losing weight doesn’t always help people who are skinny with belly fat.
The second group of participants were given a cardio workout routine in addition to their fat-loss diet. Here are their results:
This group lost the same amount of weight, but by adding cardio to their diets, they were able to lose more fat while preserving more muscle. This time, only 1/4 of their weight loss came from muscle mass. That’s slightly than the fat-to-muscle ratio that most people gain weight with, so now they aren’t just getting smaller, they’re also improving their nutrient partitioning, improving their body composition. This is a solution. But it’s not a perfect one.
The third group of participants had resistance training added to their fat-loss plans. Here are their results:
Again, this group lost the same amount of weight, but by adding resistance training to their routines, they were able to preserve all of their muscle mass. 100% of the weight loss came from fat. This is the path out of skinny-fatness. This is how to burn pure belly fat.
In fact, by improving just a few variables, we can probably help you build muscle at the same time as losing fat, as evidenced in a follow-up study:
In this second study, we see that the participants who combined a fat-loss diet with weight training were able to lose fat while simultaneously gaining muscle. Because they were losing weight overall, we’d call this cutting, but since they were building muscle at the same time, you could also call this body recomposition.
What’s the takeaway from this research? First, cardio is actually quite helpful for skinny-fat guys, and don’t let anyone tell you otherwise. Not only is it good for our general health, but it also helps with nutrient partitioning. But even so, weight training is far, far more important. If you can do both, great—that’s ideal. But if you only have 2–3 hours per week to exercise, better to spend that time lifting weights. It’s by far the fastest way to burn fat while maintaining or even gaining muscle mass.
Now, what’s the best way to get into lifting weights? The first thing to keep in mind that is that different types of resistance training are designed with different goals in mind. Strength training is designed for people who are trying to get stronger for their size, Olympic weightlifting is for people who are trying to develop explosive power, CrossFit is for people trying to improve their general fitness, and hypertrophy training is for people who are trying to build muscle. If your goal is to build muscle, best to do the type of weight training designed specifically for that goal: hypertrophy training.
We have a beginner’s hypertrophy program for men, a beginner’s hypertrophy program for women, and an intermediate hypertrophy program for people who already know how to lift weights. Or, if you want to start with bodyweight training, here’s our free bodyweight workout guide.
Eating Enough Protein
By far the most powerful way to improve your body composition is weight training. If you’re skinny with belly fat, that’s the place to start. But once you’re in the habit of lifting weights, we can further improve your results by ensuring that you’re eating the building blocks that muscle is constructed with: protein.
Now, simply increasing your protein intake won’t do much by itself, just like how tossing a bunch of blocks onto the ground isn’t a great way to build a castle. But if you’re already working out, the nuclei in your muscle fibres are already fighting to build that castle as fast as possible, and so you can help them out a great deal by giving them more building blocks to work with. This gives us a 1, 2 sequence: lift weights then eat enough protein.
If we look at this study, all of the participants were put on a hypertrophy training program and instructed to eat in a calorie deficit. Half of them ate a fairly average amount of protein (about 0.5 grams of protein per pound bodyweight per day) whereas the other half were instructed to eat a gram of protein per pound bodyweight. For a 150-pound man, that’s 75 grams versus 150 grams of protein per day. Here are their results:
After four weeks, the participants who were eating a standard amount of protein lost 7.7 pounds of fat but failed to gain a statistically significant amount of muscle. That’s a great improvement in body composition, and their results were absolutely worth celebrating… but the group who was eating enough protein lost 11 pounds of fat while gaining 2.6 pounds of muscle. They achieved body recomposition while cutting.
Notice that we’re saying “enough” protein, not “more” protein. There’s a limit to how much protein we need. We need to give the nuclei in our muscle fibres the building materials that they need, but beyond that, any extra protein we eat will be used as energy, just like fats and carbs. There’s nothing wrong with eating extra protein, but there’s no advantage to it either. About a gram of protein per pound bodyweight per day is enough. More than that is fine but won’t yield additional benefits.
The takeaway here is that lifting weights is the most important part of burning fat while maintaining your muscle, and it’s often enough to cancel out muscle loss while cutting. But we can get even better results by eating enough protein: 1 gram of protein per pound bodyweight per day.
Getting Enough Sleep
After you’re in the habit of lifting weights and eating enough protein, the next most important intervention is improving your sleep. Now, keep in mind that there’s a sequence to this plan. If you aren’t lifting weights, improving your sleep might improve your energy, hormones, mood, and general health, but it won’t do very much to improve your body composition. In fact, plenty of get-it-done personality types get great results by waking up early to squeeze in their workouts. But we can do better than that.
A recent study investigated the affect of sleep on muscle growth and fat gain when combined with a weight training program. Half of the participants were given just the weight training program, whereas the other half were also given advice about how to improve their sleep. Here are their results:
The results of this study show that simply by learning some tips about how to improve our sleep, we can increase our rate of muscle growth by 30%. It gets better, too. Look at what happened to their fat gains:
So what we’re seeing is that group who lifted weights gained more muscle than fat, but they still gained a bit of fat. They improved their body composition, and these are great results, but the group who improved their sleep did much, much better. Not only did they build 30% more muscle, they also lost fat at the same time—body recomposition.
Previous research found this same nutrient partitioning effect. And a third study found a possible mechanism for this: getting enough good sleep increases our muscle-protein synthesis. Plus, in addition to helping us build muscle more quickly and leanly, getting better sleep can also improve our workout performance (study, study) and lower our overall inflammation (study). Overall, this research shows that sleep is a powerful tool for improving nutrient partitioning—for shuttling the food we’re eating towards muscle growth instead of fat gain.
Perhaps most interestingly of all, the study participants weren’t put in a sleep lab or anything fancy. They were simply given tips to help them improve their sleep. These are results that you can get at home, from the comfort of your very own bed.
So, how do we improve our sleep? It ultimately boils down to two things:
- Get enough sleep: 7–8 hours is enough for most people, and I recommend experimenting with the higher end. If you find yourself routinely waking up an hour early feeling refreshed, then that’s a sign you may need less sleep.
- Get better quality sleep: ideally you want to fall asleep easily and then get a restful sleep without waking up too many times during the night. The most important factor is reducing your stress before bed, which can be done by relaxing away from screens, work, and notifications. For example, going into your study or bedroom an hour before bedtime to read a speculative fiction novel by dim lamplight.
There are quite a few strategies for improving your sleep, though, and we cover all of them in our free guide on improving sleep for muscle growth.
Being Generally Healthy
The big three interventions for building muscle while burning belly fat are weight training, eating enough protein, and getting enough good sleep… but there are a bunch of other smaller factors. You don’t need to worry about them right away, but they’re good to keep in mind, especially if you’re looking for an edge. Plus, all of these interventions improve our body composition by making us healthier, which is perhaps the most important thing of all.
So, there are a few important parts of living a healthy lifestyle. There are millions of small details, but painting with broad strokes here, we can paint a rough picture:
- Eat mostly whole foods—around 80%. Whole foods are hard to define, but you know them when you see them. Fish, chicken, eggs, cheese, yoghurt, oats, fruits, nuts, legumes, veggies, and olive oil, are all fairly clear examples of whole foods. But what about milk, whey protein, rice, tortillas, and whole-grain bread? Those foods are all at least somewhat processed, but they aren’t exactly junk food either, right? Right. If you want to count those as whole foods, no problem—close enough. Or if you think white rice is the insulin devil, no problem—don’t eat it. We don’t need to sweat these small details.
- Spend some time walking outside every day, even when it’s raining or snowing or you’re feeling lazy. Some people do this by walking to class, walking to work, or walking their dog. But the important thing is to make walking outside a regular part of your lifestyle. Not only will that give you some sunshine, improving your vitamin D production, it will also help to keep you fit.
- Keep your alcohol consumption under control. Most research shows that women are fine with one drink per day, men with two. Is it even better to drink even less? Maybe. Again, it’s hard to say because it doesn’t seem to matter very much. As long as you aren’t overdoing it, it seems fine to have a drink or two most nights. It won’t noticeably impact belly fat or muscle growth (study). It’s only when drinking starts to get out of hand that it starts to cause problems.
- Manage stress. There’s nothing wrong with being stressed now and then. But try to set aside some time for relaxation, too, so that the stress doesn’t become chronic and overbearing. Obviously, this is easier said than done, but even small interventions like setting aside an hour before bed to read a relaxing novel can help to separate stress from sleeping, giving you a needed break. Fortunately, exercise and improving your sleep both seem to help with mood and stress, so in the process of improving your body composition, you may notice that your stress levels naturally start to ease.
We have a free guide on how to bulk the healthy way, but even just loosely following these tips can go a long way. If you’re in the habit of working out, eating enough protein, eating mostly whole foods, getting enough sleep, spending some time walking outside, and you aren’t crippled by stress, most research shows that you’re doing the most important things for your general health.
If you’re a skinny-fat beginner who’s new to all of this, you don’t need to think about your energy balance right away. As with the rest of these interventions, there’s a sequence to this. If you start by manipulating your energy balance, you run the risk of losing muscle while losing weight or gaining fat while gaining weight. Energy balance is an important factor, but it relies on understanding nutrient partitioning. We need to make sure that when we lose weight, we’re burning fat, and maybe gaining a bit of muscle. We need to ensure that when we gain weight, we’re gaining mostly muscle, and maybe even losing a little bit of fat.
But once you’ve gotten into the habit of weight training, eating enough protein, getting enough sleep, and leading a generally healthy lifestyle, your nutrient partitioning will be good, and so it’s time to starting speeding things up by manipulating your calorie intake.
- If you want to burn belly fat faster: start eating fewer calories, losing weight, cutting.
- If you want to gain more muscle size and strength: start eating more calories, gaining weight, bulking.
Now, we’re not saying that you should eat a starvation diet, nor are we saying that you should bulk so aggressively that you gain a ton ton of fat. No, we’re saying that you should think about steadily losing weight with a modest calorie deficit of around 500 calories per day. We’re saying that you should think about slowly bulking up with a calorie surplus of around 250 calories per day.
Counting calories can be helpful, but you don’t need to. If that’s too much hassle, weigh yourself every week, and think about “eating a bit more” or “eating a bit less.”
- If you’re struggling to gain weight, think about adding in a smoothie, adding snacks between meals, having a glass of milk with meals, or adding some extra starchy carbs to your meals (more rice, pasta, beans, bread, etc). We’ve got a free guide on eating more calories here.
- If you’re struggling to lose weight, think about cutting back on liquid calories, cutting back on snacks, eating more protein, eating more berries, eating more fibre, eating less junk food, and avoiding eating out of boredom while lounging—while watching TV and whatnot.
None of these are perfect solutions. When you’re slowly gaining weight, you may find yourself feeling perpetually full. When you’re losing weight, you may find yourself dealing with hunger pangs and cravings. These things should be expected. They aren’t a sign that you’re doing anything wrong. Just keep weighing yourself every week and adjusting your calorie intake accordingly.
The Big Five Approach to Skinny-Fatness
Alright, so we’ve gone over five main interventions that will help you to burn belly fat while building muscle, allowing you to steadily climb your way out of skinny-fat hell:
- Lift weights to stimulate muscle growth.
- Eat protein to build the muscle with.
- Get enough good sleep.
- Try to lead a generally healthy lifestyle.
- Eat the right amount of food.
We’ll call these the Big Five. There are a myriad of other ways to improve body composition, but most of them slot themselves into those four main categories, and often in a minor way.
If you hear that doing sets of 6–15 reps builds more muscle than doing sets of 3–5 reps, or that reverse pyramid training (RPT) is a good way to train, or that we should focus on compound lifts, that we should add isolation lifts to our routines, or that we should push ourselves close to failure—that can all be true, and it slots into intervention #1: weight training. But these are just details. The most important thing is weight training.
For example, if you hear that supplementing with BCAAs or whey protein, or eating more meat, or focusing on higher-protein foods will help your body composition, that’s true, and it slots into intervention #2: eat enough protein. If you’re eating enough protein, these details stop mattering very much.
Even when it comes to things like balancing out your carb and fat macros, yes, that can matter… a little bit. But if you’re already eating a generally healthy diet made up of mostly whole foods, it probably won’t matter enough to be noticeable. When it comes to plant-based diets, ketogenic diets, and intermittent fasting, all of those approaches can work, but don’t expect to get better results from them. In fact, most of them tend to make it at least slightly harder (or at least more complicated) to build muscle.
There’s nothing wrong with experimenting with supplements (such as creatine), neat training ideas (such as neck training), or interesting dietary approaches (such as intermittent fasting), but they aren’t powerful enough to rely on. If you aren’t happy with your results, don’t turn to weaker solutions, turn to stronger ones. Turn to the Big Five. And if the Big Five aren’t working, refine them. If your lifting program isn’t allowing you to add weight to the bar every couple weeks, think about improving your training program, eating more protein, eating more calories, getting better sleep, or, as a last resort, restricting yourself to just two margaritas per day.
What About Body Recomposition?
Body recomposition is viable… sometimes. If you’re still new to all of this, it’s okay to start with weight training, increasing your protein intake, improving your sleep, and trying to lead a healthier lifestyle. That will often be enough to simultaneously build muscle and burn belly fat, especially if you fall into one of the following categories:
- New lifters: skinny-fat guys who are new to weight training will be able to make newbie gains even if they don’t gain weight overall. This is because their muscles are still so sensitive to muscle growth, still extremely far away from their genetic potential.
- Detrained lifters: if you were muscular in the past but you’ve let yourself get out of shape, then you’ll be able to take advantage of muscle memory, regaining your lost muscle without needing to be in a calorie surplus. (This includes guys who are still in the habit of lifting, but who aren’t as big or strong as they used to be.)
- Overweight guys: if you have quite a lot of extra body fat, you might be able to burn fat while building muscle.
In these situations, body recomposition can make sense. Instead of focusing on calories, you can focus instead on weight training, adding weight to the bar, fighting for more reps, eating enough protein, improving your sleep, and leading a healthier lifestyle. As you do those things, you may find that you gain muscle while losing fat, even if your body weight stays about the same.
However, in all of these cases, you’d be able to build muscle while losing weight, too. You can achieve body recomposition while doing a modest cut. And if you do that, you can burn fat much, much faster. Plus, there are also situations where body recomposition is contraindicated. Let’s imagine some examples:
- You’ve been following a lifting program for a few months, you’ve hit a strength plateau, and you aren’t happy with how your body is looking. You’re feeling a bit chunky and your muscles aren’t as big as you’d like them to be. In this case, you’ve probably gotten your newbie gains, and you’re also finding it hard to build muscle and burn fat simultaneously, meaning you need an easier, more powerful solution.
- You’ve got a bit of belly fat but you’re also skinny and technically underweight. Since you’re technically overweight, it might be hard to burn fat without actually losing weight. And since you don’t have much extra body weight to work with, it might be hard to build muscle without gaining weight.
- You’re an intermediate lifter who’s over-bulked and lost his muscle definition. In this case, you’ve already made your newbie gains, your muscles are in peak condition, and it’s going to be very hard to continue building muscle without gaining weight. Since you can’t build muscle without gaining weight, that also means that the only way to lose fat is to lose weight.
- It’s not working and you need something more powerful. If you’re experimenting with body recomposition and it’s not working—you’re not burning your belly fat, getting stronger, or gaining muscle size—then you need a more powerful approach. It’s time to manipulate your calorie intake.
So there are situations where it makes sense to bulk to gain muscle and to cut to burn belly fat. When doing that, solve the bigger problem first.
- If you’re underweight, start slowly gaining weight to build more muscle.
- If you’re overweight, start slowly losing weight while fighting for muscle growth.
- If your belly fat is stressing you out, start with a cut, but fight to gain strength while you do it.
- If you’re worried that your arms are too small, start with a modest bulk, gaining weight slowly to keep any fat gain minimal.
Overall, body recomposition is a good idea if you’re new to lifting, newly getting back into lifting, or you’re still trying to develop a good lifestyle. But if you’re starting to get frustrated by a lack of progress, it’s time to turn the energy balance dial, either cutting or slowly bulking.
Why’s All Your Fat in Your Belly?
There are a few reasons why people have disproportional amounts of belly fat. The most obvious reason is that men store most of their fat in their midsections, and so when men become overweight, they tend to get bigger bellies. It’s not necessarily any great mystery, it might just be that you have a classic male body-fat distribution pattern and you’ve gained too much fat.
That doesn’t explain why you’re skinny except for your belly. But that doesn’t necessarily have anything to do with fat, it might just be that you haven’t built much muscle yet. When we gain muscle, most of it is in our legs, arms, and around our shoulder girdle—our upper backs, shoulders, and chest. So as we gain muscle, we get bigger everywhere but our stomachs. That means that if we’re skinny with belly fat, it tends to mean that we have too much fat and too little muscle overall. It’s not that we’re storing fat oddly, it’s just that we’re out of shape.
As I gained 60 pounds, I gained thirteen inches around my shoulders and only around two inches around my waist. That’s because most of the weight I gained was muscle, and so most of my measurement increases were in my shoulders, arms, and legs. It didn’t require doing anything special, and there were no real shortcuts, I just had to build a whole bunch of muscle by lifting weights, eating enough protein, improving my diet, improving my sleep, and gaining weight overall.
However, there’s a more insidious reason that some men have thicker midsections: visceral fat. Visceral fat is the unhealthy type of fat that accumulates around our organs, and in sufficient quantities, it can cause all kinds of health problems. We gain a disproportional amount of it when we eat poor diets, eat too many calories, and fail to get enough exercise. The good news is that the solution is fairly straightforward: work out, eat enough protein, improve your sleep, lead a generally healthy lifestyle, and and lose fat overall. There’s no magic secret, we just need to get in better shape.
If you’re a skinny guy with belly fat, your main problem is nutrient partitioning—you’re storing fat instead of building muscle when you gain weight, and you’re losing muscle instead of burning fat when you lose weight. Over time, that can make people skinny-fat.
There are five key ways to fix skinny-fatness:
- Lift weights to stimulate muscle growth. Hypertrophy training (aka bodybuilding) is best, but any type of weight training will do. Even bodyweight training or resistance bands can work in a pinch. Nothing improves nutrient partitioning by nearly as much as lifting weights, making this the obvious place to start.
- Eat enough protein to build muscle at full speed. Muscle growth is stimulated by your workouts, at which point you need to make sure you’re eating enough protein to build that muscle out of.
- Get enough good sleep. By improving your sleep, you can improve your workout performance, anabolic hormone production, rate of muscle growth, and rate of fat loss. It also helps dramatically with nutrient partitioning.
- Try to lead a generally healthy lifestyle. There are a million ways to improve your health, and most of them will have at least a minor impact on your body composition. By leading a lifestyle that’s healthy overall, you can combine many of these minor factors to the point where the can produce a noticeable impact. Start by focusing on exercising regularly, going on a daily walk outside, eating a diet made up mostly of whole foods, managing chronic stress, and keeping your alcohol consumption under control.
- Eat the right amount of food. Once you’re in the midst of doing the four interventions above, the best way to improve your results is to manipulate your weight. Eating more calories and slowly gaining weight (bulking) will dramatically improve your rate of muscle growth. Eating fewer calories and losing weight (cutting) will radically improve your ability to burn fat.
There are tons of other strategies to help you burn fat and build muscle, and many of them work. Most of the strategies that work fold into one of five interventions above. For instance, intermittent fasting makes it easier for some people to eat fewer calories—part of intervention #5. There are strategies that fall outside of these five interventions, and they may help in a minor way, just don’t let yourself be distracted by them.
If something isn’t working, look to the Big Five Interventions. They are by far the most powerful tools we have at our disposal. Think on improving your workout program, double-check your protein intake, make sure you’re eating real food, cut back on IPAs, or adjust your calorie intake. That is probably where the problem hides.
As always, if you want a customizable workout program (and full guide) that builds these principles in, check out our Outlift Intermediate Bulking Program. We also have our Bony to Beastly (men’s) program and Bony to Bombshell (women’s) program for skinny and skinny-fat beginners. If you liked this article, you’ll love our full programs.