Our specialty is hypertrophy training. More specifically, we help naturally skinny “hardgainers” bulk up. But before that, Marco worked as the strength coach for several college, professional, and Olympic athletes. He also interned under Eric Cressey, the strength coach overseeing the training of the Yankees. So we’ve got somewhat similar roots to Jeff Cavaliere. Not surprisingly, then, we get a lot of questions about his muscle-building program for skinny guys.
Inferno Max/Size is the workout program for hardgainers who are looking to build muscle. That’s the Athlean-X program that best lines up with our area of expertise. So let’s evaluate it based purely on how effective it is at helping hardgainers bulk up.
Before we decided to build our careers around helping hardgainers build muscle, Marco was a strength and conditioning coach for high-level athletes, including college, professional, and Olympic football and rugby players here in Canada. After getting his degree and certifications, he then interned under Eric Cressey, the strength coach overseeing the strength and conditioning of the Yankees. We’ve got those same roots in athletics training as Jeff Cavaliere, and so a lot of our readers have been asking us what we think of his muscle-building program for hardgainers.
That also introduces somewhat of a problem. We’re naturally skinny guys ourselves, and I’ve personally gained 60 pounds at 11% body fat. Marco has gained almost 70 pounds. We then went on to create our Bony to Beastly and Bombshell blogs, and we’ve been working full-time helping skinny people bulk up for nearly ten years now. Helping hardgainers build muscle is our specialty, making us well-suited to reviewing this muscle-building program, but it also gives us a bias.
On the other hand, we’ve mainly heard great things about Athlean-X. We have a lot of members who did Jeff Cavaliere’s programs before coming to us. Not all of them succeeded at building muscle when doing the Max/Size program, but many did. And more importantly, he got them into the habit of weight training. Anyone who can do that is doing a great thing.
Plus, we’re more than happy to say great things about great programs. Eric Cressey makes great bulking programs for athletes, Eric Helms makes great hypertrophy programs for intermediate bodybuilders, and Greg Nuckols makes great strength and hypertrophy programs for powerlifters. But even so, take this review with a grain of salt.
As we review Inferno Max/Size, I don’t want to reveal too much of the workout program. I bought the program and I have it right here in front of me, but I’m intentionally being vague and giving away as few details as possible. That way if you want to learn more or try the program for yourself, you still need to buy it. I do want to talk about the training methods being used here, but I think I can do that without giving any of the magic away.
Max/Size is the Athlean-X program for hardgainers who are looking to build muscle. Helping hardgainers bulk up is our area of expertise, so let’s take a look at the program and evaluate it for its ability to stimulate muscle growth.
The Max/Size Workouts
Max/Size starts with workouts that are built around two training methods. First, there’s German Volume Training for two compound barbell or dumbbell lifts (as is typical with German Volume Training). Then there are two finishers, training the same movements but with lighter variations or with our own bodyweight.
The workout routine is a body-part split, with each workout focusing on just two muscle groups. For instance, chest and back, quads and hamstrings, or biceps and triceps.
Is that an effective way to stimulate muscle growth? Let’s go into the details one by one.
German Volume Training (10×10)
The Max/Size workout program is built around a method that Jeff calls XV-10, also known as German Volume Training (GVT). This method involves doing 10 sets of 10 repetitions (10×10) with 60% of your 1-rep max and 60 seconds of rest between sets. For example, the first workout starts off a 10×10 on the incline dumbbell bench press.
I’ve seen Jeff criticized by strength coaches for programming 10x10s with 70–80% of our 1-rep max. That weight is too heavy to get that many reps with, especially with such short rest periods. But that isn’t an issue here. He correctly recommends using 60% of our 1-rep max. This is standard German Volume Training.
Doing 10 repetitions per set is great for stimulating muscle growth, and although most hypertrophy programs take advantage of longer rest periods, there’s nothing inherently wrong with using shorter rest periods. The general rule is that with shorter rest periods, we need more total sets, which is certainly the case here—we’re doing 10 sets per exercise.
The problem is that GVT isn’t an effective way to build muscle. It’s a high-volume approach to training that’s supposed to speed up muscle growth by ratcheting up the training volume. Or that’s the idea, anyway. There are two high-quality studies comparing GVT against traditional hypertrophy training for stimulating muscle growth, and both found that doing 4–6 sets per lift was enough to fully maximize muscle growth (study, study). Adding in those extra sets just increases fatigue, wear and tear, and makes the workouts needlessly difficult. As a result, the researchers concluded that GVT produced slightly worse results than traditional hypertrophy training.
The risk of injury, fatigue, and aches and pains would be lower with a more sensible amount of training volume, too. But to be fair, weight training is quite safe anyway, and if your joints started to bother you, you could always scale back the volume before it became a serious issue. The main disadvantage to GVT is that it makes the workouts excessively hard and leaves us needlessly fatigued without providing any benefit.
Also, consider that we need to factor in the opportunity cost. If we’re wasting all our time and energy doing extra sets on the bench press and row, we’re leaving less time and energy to invest into other exercises.
These findings aren’t controversial. German Volume Training isn’t widely used in strength training, bodybuilding, or athletics training, and the National Strength and Conditioning Association (NSCA) recommends against it. For more, we’ve got an article on German Volume Training, and a separate article on optimizing training volume for muscle growth.
German Volume Training is a poor way of stimulating muscle growth, and is by far the biggest flaw in this program. It’s not that it doesn’t work at all, it’s just that it doesn’t work very well. It’s needlessly hard and fatiguing and fails to stimulate as much muscle growth as far easier training routines.
After the German Volume Training come the “propain” finishers. As Jeff Cavaliere explains, he’s “pro pain,” and so these finishers are specifically designed to make our muscles burn with Hellfire. I’m not somebody who likes needlessly difficult training, but I love the puns and fiery branding. Anyway, these finishers work the same muscle groups as the earlier exercises. In the first workout, for example, we move from the bench press and barbell row to push-ups and inverted rows. Same movements, just lighter variations.
If we look at studies comparing the bench press and the push-up, we see that they train the same muscles and stimulate a near-identical amount of muscle growth (study, study). So stacking the two exercises one after the other is almost like making an arm day that has us doing 10 sets of barbell curls and then moving onto dumbbell curls. Problem is, we’ve already done too much volume for that movement. Why do more?
If it were me, after doing the bench press, I would choose an exercise for the muscles that weren’t properly stimulated by the first two exercises. For example, if we look at the bench press, we see that it’s a good lift for stimulating growth in our chests, not so good for stimulating growth in our triceps (study).
The reason our triceps see less growth is because the long heads of our triceps work at both the shoulder and elbow joints. When we’re pressing through the shoulder joint (shoulder extension), the long head of our triceps can’t contract very hard without pulling our elbows back (shoulder flexion). To balance out that disparity, then, we can include isolation lifts such as triceps extensions.
When we combine the bench press with triceps extensions, we get a robust and balanced amount of growth in both the chest and triceps. It’s a better combination than just doubling down on another pressing movement. And since there’s an arm-day later on in the week, this would give us a better training frequency for our arms.
Now, does this mean that these finishers are bad? No. They won’t make our muscles fall off or anything, and some people might really enjoy them. Doing multiple sets of push-ups to failure after being ravaged by German Volume Training is brutal, and I think the savageness of these Athlean-X programs is part of why people like them.
These finishers don’t do a great job of complementing the main compound lifts, especially since the volume on the compound lifts is already excessive. On the other hand, some people may enjoy how challenging they are.
The Body-Part Split
Max/Size uses a training split that trains our chest and back, then our quads and hamstrings, then our biceps and triceps, and then our shoulders and traps. There’s also an “active recovery” workout that runs through a quick full-body circuit of isometric exercises (where the weight is held in place).
I don’t see any huge issues with this training split. Our muscles grow best when we train them at least 2–3 times per week, and this workout routine does that for most of our upper-body muscles. Our biceps and triceps get a bit of stimulation when we’re training our chests and backs. Similarly, our chests and backs get a bit of stimulation when we train our biceps and triceps. There’s just one leg workout per week, which isn’t ideal for leg growth, but I don’t know who would want to do 10×10 sets of squats twice per week, so in a way, that’s a blessing.
This body-part split probably isn’t the most efficient way of training, and I think another training split might do an even better job of stimulating muscle growth, but I think it’s reasonable, and I bet a lot of lanky-limbed hardgainers enjoy having a dedicated arm day like this one.
One of the most important parts of building a good hypertrophy program is choosing lifts that are good for stimulating muscle growth and that we can do properly. Right in the very first video, Jeff Cavaliere explains that this program is good for helping beginners who are struggling to put on their first 15–20 pounds of muscle and for advanced lifters. That creates a bit of a problem. As you can imagine, the lifts that are best for an advanced lifter may not be ideal for someone who hasn’t mastered their lifting technique yet.
If this workout program is for newer lifters who aren’t training with an in-person coach, I think these exercises might be needlessly complicated. The more complicated a lift is, the harder it is to stimulate muscle growth. It may also—debatably—increase our risk of injury. I’d much rather see novice lifters starting with squat, deadlift, and row variations that are easier to learn
For instance, a lot of beginners have trouble doing back squats to a decent depth without jamming at their hips, which can prevent them from working their quads through a deep range of motion, and thus makes the lift worse at stimulating muscle growth. Using a partial range of motion also means that we need to load up heavier weights in order to challenge ourselves, putting extra stress on our knees. That’s not necessarily the end of the world, but it’s not the most efficient way to stimulate muscle growth, and a lot of beginners have trouble with it.
Instead of starting with a barbell back squat, why not something like a goblet squat? It’s much easier to learn, shrinking the learning curve and allowing us to stimulate muscle growth right from our very first workout. Goblet squats are also easier to set up, stimulate more growth in our upper backs, and they teach us how to squat through a deeper range of motion. They’re also quite a bit easier on our knees. The only downside is that once we become very strong, we need to lift something heavier than dumbbells. But for a skinny beginner, they won’t be able to do 10 reps with the heaviest dumbbell anyway, and so that’s not an issue.
Mind you, Jeff also mentioned that this program can be used by advanced lifters. And in that case, I think the exercise selection here is fairly reasonable. Lots of barbell squats, deadlifts, bench presses, barbell curls, barbell rows, chin-ups, skullcrushers, and so on. As someone who’s been lifting for a decade now, these are the sorts of lifts that I enjoy. He demonstrates pin squats through a partial range of motion, but I don’t think those are mandatory, just the variation he personally prefers.
Could the exercise selection be better for an experienced lifter? Maybe. For example, I think the flat bench press is a better lift than the incline bench press for building a big and powerful chest. It allows the chest and shoulders to be worked harder at longer muscle lengths, which can improve muscle growth. It also works our mid-chests harder, which is where most of our chest size comes from. But that’s not a big deal. Both lifts are great.
Similarly, I might choose front squats instead of back squats. They’re a bit easier on our joints, a bit safer, they bulk up our upper backs, and they usually allow for a deeper range of motion. But again, both lifts are great. I think the Max/Size lift selection is good for an experienced lifter.
Overall, I don’t think this exercise selection is appropriate for most beginners who are still struggling to gain their first 15–20 pounds of muscle. For a seasoned lifter, though, these lifts are pretty good.
Partial Range of Motion
As mentioned above, Jeff Cavaliere recommends doing partials on the squat and bench press, lowering the weights down to pins instead of bringing them to full depth. He says that this makes the lift safer, and to be fair, there are certainly people who benefit from restricting the range of motion of their lifts. But it also creates some problems:
- When we do partials, we don’t get a stretch on our muscles, which reduces the growth stimulus by quite a lot. From a hypertrophy perspective, that’s the most important part of the lift.
- Doing partials forces us to use heavier weights to keep the lifts challenging, which tends to put more wear and tear on our bodies, make our workouts more fatiguing, and make it harder to recover between sessions.
- Doing partials means that we don’t develop strength in the bottom positions. From a general strength perspective, I don’t think that makes much sense. It’s better to develop strength all through the range of motion.
Some people might need to restrict their range of motion, and that’s perfectly fine, but for the people who can manage it, I think it’s better to get a deep stretch on our muscles at the bottom of our lifts. We develop better general strength, our workouts are easier to recover from, and we can stimulate more muscle growth.
For the people who aren’t able to lift with a large range of motion on the back squat and bench press yet, instead of recommending partials, I’d choose different lifts. For example, goblet squats and front squats are amazing for teaching people how to squat deeper. And as they learn, they’re still able to train their quads through a deep range of motion, stimulating a robust amount of muscle growth as they improve their mobility.
On a similar note, Jeff recommends training our muscles at various points of the range of motion with separate lifts. One lift to stimulate our muscles in a stretched position, another for the mid-range, and another for the contracted position. At the moment, there’s no evidence to support that idea, and I’m skeptical that it helps.
If we look at the research, we see that training our muscles at longer muscle lengths stimulates almost three times as much muscle growth (meta-analysis). Plus, when we’re emphasizing different parts of the range of motion, we’re training the same muscle fibres. It’s not that different muscle fibres or heads are being stimulated.
For example, if we look at a recent study on hamstring training, we see that lifts that train our hamstrings at longer muscle lengths stimulate more growth than lifts that train our hamstrings at shorter muscle lengths. There doesn’t seem to be any benefit to doing both, it’s just that deeper is better. If we apply that same logic to our chests, then if we use lifts that train our chests in a stretched position, such as a full bench press, dip, push-up, or dumbbell fly, then there’s no need to do lifts that emphasize the contracted position, such as a cable crossover.
And besides, if we use lifts that work our muscles in a deep stretch—such as a full range-of-motion bench press or squat—then we’re training our muscles at longer muscle lengths at the bottom and at shorter muscle lengths at the top. We get the best of both worlds simply by trying to sink deep into our lifts.
With that said, any lift that challenges our muscles will stimulate at least some muscle growth, at least until we’ve reached a volume threshold where extra work just increases our recovery demands. I just think there’s a more efficient and effective way to gain muscle size and strength.
Training with a deeper range of motions stimulates more muscle growth and gives our lifts a better stimulus-to-fatigue ratio. We get faster muscle growth, less wear and tear, and we recover more easily. Not everyone can lift with a deep range of motion on every lift, but most people can find lifts that allow them to improve their mobility and train with a good range of motion.
This program features a lot of isometrics. I don’t think that’s a problem, necessarily, but as a general rule, lifting through a range of motion stimulates more muscle growth than holding a weight in place. Isometrics aren’t bad, though. They have their uses. Especially when they’re done at longer muscle lengths. So it’s not wrong for a hypertrophy training program to include some. It’s just that this program uses a lot of isometrics.
This program uses a lot of isometrics, which may not be the best use of our time or energy.
When I was a skinny guy who was desperate to bulk up, I just wanted to build muscle. I didn’t want haphazard metabolic conditioning workouts sprinkled into my hypertrophy program. And if I did want to do that, I’d want them to be a part of some overall system, not just random challenges at the end of each month. For example, when I was first bulking up, I started by doing pure hypertrophy training. But after a few months of that, I added in two 20-minute cardio workouts every week to improve my overall fitness. Each cardio workout, I would try to improve my performance. There was progressive overload built into my cardio training. It wasn’t just randomly thrown in.
But that doesn’t mean that these challenges are bad. In fact, they’re probably quite good for our general health. So no issue there. It’s just not what I would have wanted.
There are random challenges tacked onto the end of each training phase. Jeff Cavaliere is a big advocate of making things as painful as possible, and these are designed to be brutally hard. Will that increase muscle growth? Not really, no. But some people enjoy being challenged just for the sake of the challenge.
The Max/Size workout program starts off with 10 sets of 10 repetitions right from the very first workout. The problem is, when we first start a new training program, we haven’t adapted to it yet, and so our muscles are still fairly sensitive to muscle damage. We aren’t tough yet. This is true of almost everyone, but it’s especially true with novices and people who are detrained.
That means that if we start with an extremely high training volume, we cause excessive muscle damage, which can reduce muscle growth. Plus, that high training volume will also cause crippling muscle soreness, impairing our ability to do our next workout properly, and thus further reducing our muscle growth.
If someone wanted to experiment with German Volume Training, a more sensible approach would be to start by doing 2–3 sets per exercise and gradually working their way up week by week. Most people cap out at around 6 sets per exercise (which is why German Volume Training is usually a bad idea), but some people are outliers that can benefit from higher training volumes. Those outliers could continue adding sets all the way up to 10 sets per exercise. I still don’t think that’s ideal, but it would be a more reasonable way to progress into classic German Volume Training.
As we progress through the Max/Size workout routine, the rep ranges and exercise order are shuffled from workout to workout, and the training methods are changed from phase to phase. Some people find that way of training more interesting, but it also makes it harder to measure our progress to see if we need to adjust our training. Mind you, it’s not that varying our workouts like this impairs muscle growth. In fact, there’s research showing that varied workouts stimulate muscle growth equally well as if we kept the variables more consistent (study). But there’s no advantage to it. It just makes our progress harder to gauge.
There are also some peculiar methods being used here, such as doing concentric-only training one day and then doing eccentric-only training the next day. That seems like a very inefficient way to stimulate muscle growth, and I’m not sure there’s any research to support it. I suspect it would be more effective to keep the phases more similar to one another but to put more emphasis on progressive overload.
There’s no emphasis on progression or progressive overload in this program. It starts off way too intense right out of the gate and then variables are shuffled around from week to week to keep things interesting. That’s not the best way to stimulate muscle growth, but it can work in a pinch.
Some of Athlean-X’s diet advice is great. The meal plan includes some perfectly good recipes and he recommends swapping out the things we don’t like for things that we do like. When we’re struggling to gain weight, that’s crucial. Better to eat a diet that we enjoy, can afford, that fits our schedule, and that we can digest well. He also stresses that we don’t need to swap out all of our meals for the ones he provides and that the best we can do is good enough—that getting things 90% right is fine. I love that.
Some of the diet advice is more questionable. He subscribes to the old bodybuilder method of eating every 2.5–3 hours to “keep your muscle-building factory in full operation” and to “keep your blood sugar stable.” Eating at least three meals per day can improve our ability to build muscle, and there’s nothing wrong with eating more often than that, but we don’t need to eat every 2.5–3 hours, and our blood sugar won’t be an issue regardless of our meal schedule. So there’s a bit of fearmongering there, perhaps. But with that said, some hardgainers find it helpful to eat lots of meals and snacks. We often have smaller stomachs than the average guy, and so eating smaller meals more frequently makes it easier to eat enough calories to gain weight. So this is by no means a bad way to bulk, it’s just not the only way to bulk.
There’s some nonsense in here, too. Jeff Cavaliere says that sweets “do nothing for helping your muscles repair themselves and grow larger.” He also says that they don’t give us useable energy. That’s just flat wrong. Simple carbs are easily converted into energy, and so most athletes eat quite a bit of sugar or starch. We don’t need to eat any processed sugar, but it’s unlikely to harm our ability to build muscle quickly and leanly, and sugar absolutely contains energy that our bodies can use. Our muscles are literally full of sugar. Muscle glycogen is sugar. Our muscles are powered by sugar.
Some advice is missing, too. He recommends taking protein supplements, but he doesn’t give a daily protein target. Most research shows that we can maximize muscle growth with 0.8–1 gram of protein per pound bodyweight we day. That’s useful information to know. Most people don’t eat that much protein, and so when we first start bulking, it can really help to track protein intake for a few days to make sure that we’re eating enough of it.
The main problem, though, is that he makes no mention of adjusting calorie intake based on whether we’re gaining weight or not. That’s a recipe for disaster when working with hardgainers who are struggling to build muscle. To build an appreciable amount of muscle as a skinny guy, we need to eat in a calorie surplus. That’s easier said than done, and so to make sure that we’re succeeding at that goal, we need to weigh ourselves every week and adjust our calorie intake accordingly. If we aren’t steadily gaining weight, we need to increase our calorie intake.
This diet contains some bro-science and incorrect information, and it might make people a bit fearful about eating sugar or sweets, but I think it’s a reasonable muscle-building diet if people already know how to eat enough protein, eat enough calories, and gain weight steadily on the scale each week.
Sleep is an underrated aspect of building muscle. By improving our sleep, we can build muscle faster and gain less fat while doing it (study). So I like how Jeff Cavaliere mentions sleep in this program, saying that you should “aim for 7 hours of sleep a night to give your body the best ability to recuperate and restore your energy levels.”
We generally recommend a little more sleep than that, but his advice lines up the recommendations of the American Academy of Sleep Medicine (source), so no problem there. It’s possible to go much deeper into improving our sleep, and given how important it is when trying to build muscle quickly and leanly, I would have wanted more than a single sentence on it. But his advice is solid, and I appreciate that he mentions it at all.
I think the sleep and overall lifestyle recommendations in this program could be more detailed. On the other hand, not every bulking program needs to have everything in it. There’s only so much it can include.
Tracking and Progress
There’s no mention here of taking progress photos, measuring our muscles, or evaluating our progress in any way. One of the most essential parts of making a good muscle-building transformation, especially if you’re trying to do it in a short period of time, is to measure your progress and adjust accordingly.
If a week goes by and you haven’t gained weight, you need to increase your calorie intake. If you complete a phase of the program and your muscles haven’t grown bigger, you need to adjust something. Or what if you notice that you’re gaining weight and getting bigger but you’re also gaining too much fat? What then? Who knows. It doesn’t say.
If someone is a hardgainer who’s having trouble building muscle, I’m not confident that this program will give them the toolkit they need to ensure steady and consistent progress as they go through the program.
The Athlean-X Inferno Max/Size workout program by Jeff Cavaliere promises muscle growth. For people who know to eat enough calories and protein, it will deliver on that promise. The workouts might not be ideal, but they’re certainly rigorous enough to provoke muscle growth.
- The program is built on a foundation of compound free-weight lifts, such as the squat, incline bench press, deadlift, and barbell row.
- The rep ranges are reasonable for stimulating muscle growth.
- Short rest times can be okay for stimulating muscle growth.
- The training split trains our upper-body muscles twice per week.
However, I think it’s important to compare this program against the industry standard, and it’s not as good as a traditional hypertrophy program. Here’s why:
- This program uses German Volume Training (10 sets of 10 repetitions), which has fared quite poorly in the research and isn’t advised for building muscle. Traditional set and rep schemes (such as 4 sets of 10) are not only quicker to do, but they’re also easier to recover from and produce better results.
- The exercise combinations could be better. For example, instead of doing 10 sets of the bench press followed by several sets of push-ups, it would probably be better to do 3–6 sets of the bench press followed by some triceps extensions (such as skullcrushers).
- There’s no emphasis on progressive overload from week to week, or even from phase to phase. There’s a bigger emphasis on variety than progression. That doesn’t ruin a program, but it does make it harder to gauge if we’re making progress or not.
- Jeff Cavaliere says that he’s intentionally promoting pain with these workouts. They’re designed specifically to be difficult. Why not design them to be effective instead?
Overall, there’s too much emphasis on making the workouts hard, too little emphasis on stimulating muscle growth, the lifts aren’t good for novice lifters, and the training is too haphazard. But to put this into context, the very first bulking routine I ever did wasn’t very good. It was a typical push/pull/legs bodybuilding routine that was made up entirely of 3 sets of 8 repetitions on a wide variety of lifts. That’s not ideal, but because I was new to lifting weights, it was enough to stimulate quite a lot of muscle growth. I was able to gain twenty pounds during my first three months of lifting. I don’t think Max/Size is as good as that bodybuilding program, given that it strays so far from what has proven to be effective, but I think the effect would be similar. These workouts are enough to stimulate muscle growth.
If you’re a new lifter, the most important thing is that you start lifting. If this program gets you motivated to train, absolutely buy it. Even though it may not be the best hypertrophy program for a skinny novice lifter, we’re nitpicking here. If you combine these workouts with a good bulking diet and lifestyle, you’ll finish the program bigger than when you started it.