How A Skinny Guy Gained 10 Pounds in 5 Weeks

The skinny man on the left is Jeff before starting the Bony to Beastly Bulking Program. He started the program at 136 pounds with internally rotated shoulders, a head that jutted forward, and a posture that made his belly stick out—issues that he was eager to fix. Most of all, though, Jeff was tired of being skinny and eager to bulk up.

The muscular man on the right is Jeff 5 weeks later, weighing in at 146 pounds and with most of his postural problems greatly improved. He also succeeded in balancing out most of his muscle asymmetries. Most of all, though, he had succeeded at gaining 10 pounds. In just 5 weeks, he had overcome his skinniness. And he was still just getting started.

Before and after illustration of an ectomorph's progress as he gains muscle.

Jeff, A Regular Skinny Dude

Jeff’s a 34 year old graphic designer and photographer with a wife and two kids. He grew up skateboarding, surfing, snowboarding, and, like most of us naturally skinny “ectomorphs” or “hardgainers,” he’d been trying to gain weight for several years now. And he’d been failing.

What impresses me about his skinny-to-muscular transformation-in-progress is not so much the change, but rather the timeframe. This is just five weeks of progress. He’s only a quarter of the way through the workout program. And that’s not unusual. Thanks to the phenomenon of “newbie gains,” early results tend to come quickly. It’s only when we start to become muscular that our rate of muscle growth starts to slow.

That means that when a skinny guy first starts bulking up, things change quickly. In just a single week, you can be up 1–3 pounds on the scale, and in just a single month, you can start to see noticeable changes in the mirror. Jeff’s shoulders are measurably broader, his chest is measurably bigger, he’s quite visibly developing his abs are starting to pop, and, although you can’t see it in this photo, his legs and glutes have exploded in size.

Eventually, his rate of muscle growth will start to slow, but right now, he’s gaining weight and building muscle very fast. That’s true for almost all of us. Most skinny guys can gain weight quickly without gaining a noticeable amount of fat. It’s not all muscle, but since our body-fat percentage isn’t going up by very much, it looks like it’s muscle.

How Jeff Gained 10 Pounds

During his very first week of bulking, Jeff didn’t gain any weight. He’s a skinny guy, a hardgainer. That’s normal. Most of us struggle to gain weight. Not because we have bad genetics, just because we have smaller stomachs, more modest appetites, and more adaptive metabolisms. So we told him what we tell everyone: you’ve got to eat more calories.

Illustration of a skinny hardgainer eating a feast in his attempt to bulk up, gain weight. and build muscle.

For most skinny guys, that’s like being told that you need to eat more cockroaches. Eating more calories is just a gross, awful thing to need to do. But Jeff, brave ectomorph that he was, added an extra 300 calories to his daily calorie goals. And the next week, he gained nearly 4 pounds on the scale.

Is that 4 pounds of pure, hard, dense muscle? No, of course not. Most of that weight is the extra food in his stomach, extra glycogen in his muscles, and maybe some extra water retention. Creatine can cause our muscles to grab onto some extra fluid, too. The first week of being in a calorie surplus is always wild, so we don’t really pay much attention to those gains.

The important thing is that Jeff had started gaining weight. And his lifts were going up, too. He was adding weight to all of his lifts, eking out extra reps, and improving his lifting technique. Things were starting to come together. The bulk was starting to work. He was getting bigger and stronger.

In his second week, he’d gained another pound. And then the week after that, he gained another. And now we’re not talking about extra stomach contents anymore, we’re talking about bonafide weight gain. This is where the momentum really starts to help us. We can see our strength increasing, see subtle changes in the mirror.

Jeff posted his progress update in the community, noting that he’d been gaining weight steadily for the past few weeks. Another skinny guy in the community, Obe, was inspired, asked him how he was building muscle so quickly. Here’s what Jeff told him:

Hi Obe. After my first week’s failure at gaining anything I knew that I needed to take eating serious, real serious. Probably the thing that helped me the most was having multiple options with food and lots of it in the fridge, and also using a calorie counter to track my intake. When I go to the store I will buy 3 tubs of greek yogurt instead of one to keep the fridge full. Things like that. I have staple foods that I eat pretty much everyday at some point and supplement that with high protein foods at meal times. Usually those staples are Greek yogurt, eggs, whole milk and lots of it, peanuts, almonds, peanut butter, cheese, eggs and chicken. I also keep a drawer stocked with a few protein bars in case I am going to be out all day and I need some extra calories or protein. Making a shake on the days that food was going to be a problem has also been a huge boost as well. I try to start the day off with a huge breakfast but it doesn’t always work out that way.

My motto lately is if you’re thinking about food you should be eating lol. This last week I was putting in over 4000 calories in about half the week and probably around 3600 to 3800 the other half. I pretty much stick to the diet plan of good stuff but I am guilty of throwing in a 16 oz. white chocolate mocha with whole milk in here and there but that’s probably the worst that I do. I know that things can get expensive bulking up but I also found that I can get some things at Costco that make buying in bulk a little cheaper. Whole milk, peanut butter, eggs, dave’s killer bread, blueberries, things like that. I have taken cues from the guys here about what works for sure. Hope this helps.

By the way, Obe, I was just like you before the program. The most I had ever weighed was probably 137 or 138 and had never been able to gain when I tried. This has been such an incredible experience so far. I take my end of phase 1 photos next week and can’t wait to compare the progress. I started the program at 136 and now I am just shy of 144 at week 4. So stoked as I had never broken the 140 barrier before and now its in the rear view.

Jeff, the skinny graphic designer

What’s neat is that after taking Jeff’s advice, Obe went on to gain 20 pounds in 5 weeks, which is one of the fastest rates of weight gain we’ve seen. More impressively still, Obe still had abs by the end of it.

The Muscle-Building Workout Routine

There are a lot of ways to stimulate muscle growth, and a lot of different tools you can use, ranging from resistance bands to exercise machines to bodyweight training. All of those can work, and all have their own unique advantages. But dumbbell and barbell training tends to be the most efficient way to build muscle. And if you’re a skinny guy who’s already struggling to build muscle, it’s often best to go down the easiest path.

That doesn’t mean that you need to train at a gym, but you can—that’s what Jeff did. Another route is to buy some adjustable dumbbells or, better still, build a simple barbell home gym. Either approach will work, but barbell training tends to be a bit faster than dumbbell training, since you can choose bigger lifts and train both sides at once—front squats instead of split squats, for example.

Jeff was following our Bony to Beastly Workout Routine, and the workouts were built around the “Big 5” compound lifts:

Illustration of a skinny ectomorph doing a deep dumbbell goblet squat.
The goblet squat, a great beginner variation.

We also use a few core and posture exercises, such as planks. After all, many of us ectomorphs have poor hip, shoulder, and head posture. There are plenty of ab exercises, such as crunches, that make our abs stronger, but what’s nice about planks is that they teach us how to keep our torsos rigid under load. Planks help us become better lifters. And for skinny beginners, that can be magic for improving our squats, deadlifts, and overhead pressing.

Before and after illustration of a man with a skinny neck building a muscular neck.

And although we base our routines on compound lifts, we never shy away from isolation lifts like the chest fly, biceps curl, and lateral raise. After all, many of us naturally skinny guys have lankier arms and narrower shoulders. You may even want to do some neck curls and extensions to build a thicker neck.

Should beginners take their sets to failure to build muscle?

Plus, because these isolation lifts are so simple, they give us an opportunity to push ourselves harder, bringing our sets closer to failure without risking injury. That can speed up our muscle growth by quite a lot during those early weeks.

There’s a lot we can do to make a workout routine better for building muscle, ranging from which exercises we choose, how many repetitions we do per set, how many sets we do per muscle, how long we rest between sets, and how often we train our muscles.

But these are details, and the important thing is that we start lifting weights. It’s okay to be a beginner. It’s okay to get things wrong. What matters is that we get started, and that we fight to improve, fight to get stronger, fight to outlift ourselves. Every workout, we need to lift more than we did last time, whether that’s adding more weight to the barbell, fighting to lift an extra rep, or adding an extra set.

Illustration showing Milo of Croton gaining muscle and strength by lifting a calf as it grows into a bull.

This is the idea of progressive overload: to build more muscle, we need to lift more weight. And to lift more weight, we need to build more muscle. This is illustrated by the story of Milo of Croton, who carried a calf every day as it grew into a bull. We need to do that with our workout routine.

For more, we’ve got an article on how to train for muscle size, and another article with a sample ectomorph bulking workout.

The Muscle-Building Diet

But keep in mind that working out is just half the battle. The main thing us skinny guys struggle with is gaining weight. And no matter how hard we train, that isn’t what causes weight gain. To gain weight, we need to eat more calories. And for hardgainers, eating enough calories to gain weight can be hard.

But if you can pair a good bulking diet with a good bulking workout routine, you’ve got the perfect environment for muscle growth. The workouts stimulate muscle growth, the protein gives us the materials to build that muscle, and the calories allow us to gain weight. That’s how we can become bigger and stronger.

After failing to gain weight during his first week, Jeff realized that to get results, he needed to change his eating habits. Instead of skipping breakfast, he made a giant mass-gainer smoothie:

A photo of a smoothie that can be used to gain weight and build muscle while bulking.

Now, you don’t need to make that same smoothie. You can eat whatever you want for breakfast. But for a lot of skinny guys, getting a big influx of liquid calories is a good way to drive ourselves into an easy calorie surplus. Plus, with something like a smoothie, we can also use it as an opportunity to get in a ton of healthy bulking foods: spinach, nuts, yoghurt, fruits, berries, oats, and so on. It’s a chance for us to not only eat more calories, but to eat more nutrient-dense calories.

There are a ton of other tricks. If it’s hard to find the time or energy to cook dinner, maybe it makes more sense to cook up a big vat of chili or stew on Sunday, and then reheat it for dinner. Or if you’re finding your meals too big to fit in your stomach, maybe you want to sneak in some trail mix snacks between meals. If you find steak filling, eat ground meat instead, which is much easier to chew and digest. Or if you’re bloated and gassy from all the fibre, maybe eat more simple carbs instead, such as white rice. There are dozens of ways to make gaining weight easier.

Illustration of a Thanksgiving turkey

And there are other details, too. For instance, it’s important to eat enough protein, and even the ratio of carbs-to-fat that you eat can play a role in how quickly and leanly you build muscle. In our case, skinny guys and athletes often benefit from eating more carbs, and so if we’re skinny guys who are lifting weights, a moderate to high-carb diet can work quite well. For more, we’ve written an article on bulking macros for ectomorphs.

But the important thing is that you find a way to eat enough calories to gain weight. Weigh yourself every week, see if you’re eating enough calories to move the scale up, and then adjust your diet accordingly.

How Was Jeff Able to Gain Weight So Fast?

Gaining 10 pounds in 5 weeks is fast. That’s 2 pounds per week. That’s about twice as fast as we recommend for the average skinny guy. But Jeff was desperate to gain weight, eager to build muscle, and unafraid of the possibility of gaining some extra body fat. And in his case, it paid off.

We’ve seen that with other skinny guys, too. Here’s a before and after photo of GK gaining 29 pounds in 5 months:

Before and after photo of a skinny guy bulking up and becoming muscular.

And I’ve done it myself, too. I’ve gained over a pound per week without gaining a noticeable amount of fat. If you’re skinny and lean enough, it can work.

Before and after progress photos showing Shane Duquette bulking up.

So how do we do it? How is it possible to gain 10 pounds so quickly? There’s no magic secret, no oddball exercises, no weird supplements. He just started, doing the best he could as he went along. And then every time he ran into a setback, instead of giving up, we helped him work through it. The reason he gained weight wasn’t because he was doing anything weird or revolutionary, it was because he was a skinny guy with a lot of room on his frame for additional muscle mass. And because he bulked properly, consistently. And because he adjusted what he was doing based on the progress he was getting.

Was his diet 100% perfect? No, but he was eating enough calories to gain weight on the scale, and he was eating enough protein to build muscle.

Was his form perfect on every exercise? No, he’s a beginner. We can’t expect a beginner to be able to lift with perfect form. That’s why we started him off with easier variations of the big bulking lifts, and why we included plenty of isolation lifts.

How Quickly Should You Gain Weight?

Before and after illustration of a skinny guy building muscle and gaining weight.

Now, will you be able to gain weight that quickly? Yes. Your calorie intake determines how fast you gain weight. If you want to gain weight faster, all you need to do is eat more calories.

Should you gain weight that quickly? The better question is how quickly you should be gaining weight, and that’s harder to answer. Most skinny guys can build muscle fairly quickly, and so bulking aggressively can work well, but it all depends. A good rule of thumb is to aim to gain 0.5–1 pounds per week. The leaner you are, the more aggressive you might want to be. And the more skinny-fat you are, the more cautious, gaining weight more slowly.

For more, we’ve written an article about how quickly to gain weight while bulking.

Shane Duquette is the founder of Outlift, Bony to Beastly, and Bony to Bombshell, each with millions of readers. He's gained seventy pounds and has over a decade of experience helping more than ten thousand naturally thin people build muscle. He also has a degree in design, but those are inversely correlated with muscle growth.

Marco Walker-Ng is the founder and strength coach of Outlift, Bony to Beastly, and Bony to Bombshell. He's a certified trainer (PTS) and nutrition coach (PN) with a Bachelor's degree in Health Sciences (BHSc) from the University of Ottawa. He has over 15 years of experience helping people gain muscle and strength, with clients including college, professional, and Olympic athletes.