How Much Muscle Can You Gain In 3 Months? A Realistic Target For Beginners

How much muscle can you gain in 3 months

As a skinny person looking to embark on a weight gain journey, it’s important to set yourself a realistic goal. This minimizes the risk that you feel dejected and give up after failing to hit unrealistic expectations. This post explains how much muscle you can expect to naturally gain in 3 months as a beginner.

Average beginners with no prior training experience can expect to gain up to 7lbs (3.5kg) of muscle in their first 3 months of training. There may also be low and high outliers. The amount of muscle someone can achieve is influenced by factors such as genetics, gender, and program.

I managed to gain 6lbs (3kg) of muscle as a skinny newbie.

But below, I’ll also detail how much muscle others gained and what the scientific research says on the matter.

Let’s jump right in!

I gained 6 pounds of muscle naturally in 3 months as a skinny beginner.


This content is based entirely on natural muscle gains, as opposed to using anabolic steroids and other questionable substances. The dangers of steroids are well documented and we do not condone their use. As such, you should look elsewhere if that’s something you’re interested in!

Can You Gain Muscle In 3 Months?

Generally speaking, the average beginner can gain a significant amount of muscle in their first 3 months of training. The amount of muscle gained in 3 months varies from person to person. But it’s generally accepted that 3-7 pounds of lean mass gains are a realistic target to achieve.

Speaking from personal experience, I gained around 8lbs (4kg) of total body weight in my first 3 months of training.

Admittedly some of it was fat but not much (approximately a 4:1 ratio of muscle to fat so 6lbs muscle).

So I definitely agree that 3 months is more than enough time to build significant amounts of muscle.

But don’t just take my word for it.

I also compiled the answers from various personal trainers, coaches, and fitness enthusiasts from these 2 Quora threads (here and here).

Both threads asked how much muscle a beginner can realistically build in 3 months.

Quora poll results for "can you gain muscle in 3 months" and "how much muscle did you gain in 3 months" show how much muscle other people gained.

88% agreed that it’s entirely possible to gain significant muscle in the short space of 3 months.

Whilst it’s clear that the majority of people agree muscle can be built in a 90-day period, HOW MUCH muscle can be gained is an entirely different question.

There’s a lot more ambiguity here.

So I also sampled the 88% to find out how much muscle people think can be built in a 3 month period.

Whilst there was a degree of variance in the answers given, the majority 68% agreed that anywhere between 3-6lbs (1.5-3kg) of lean muscle mass can be gained in 3 months.

Therefore it’s safe to say that the majority of people not only agree it’s possible to build muscle in 3 months, but you’re also likely able to gain around 3-6lbs (1.5-3kg) of muscle in those 90 days.

How Much Muscle Can You Really Gain In 3 Months As A Beginner?

Average beginners should be able to gain between 1-7 pounds of lean muscle weight in their first 3 months of training. 1-4 pounds of muscle gain in 3 months is an achievable goal for most beginners. 5-7 pounds would require a highly optimized program. And over 8 pounds is unlikely.

You can take a look at the muscle growth rate chart below for a better idea of how much muscle you can expect to gain in 3 months:

3 Month Muscle Gain TargetProbability In Male BeginnersProbability In Female Beginners
1 poundVery likelyLikely
2 poundsVery likelyLikely
3 poundsLikelyRealistic max potential
4 poundsLikelyRealistic max potential
5 poundsRealistic max potentialRealistic max potential
6 poundsRealistic max potentialUnlikely
7 poundsRealistic max potentialUnlikely
8 poundsUnlikelyUnlikely
9 poundsUnlikelyVery unlikely
10 poundsVery unlikelyVery unlikely
15 poundsVery unlikelyImpossible
Over 20 poundsImpossibleImpossible

This table is based on the Lyle MacDonald model of expected muscle gains.

Lyle is a physiologist, author, and well-known thought leader in the field of muscle gains.

His model proposes that a complete newbie can expect to gain around 2lbs (1kg) of muscle per month (maximum) in the first year of training, equating to 6lbs (3kg) in 3 months.

In support of this, a 2011 study found that untrained individuals gained on average 6lbs (3kg) of lean body mass in 12 weeks (3 months(.

Furthermore, Stuart Phillips, Ph.D. (a highly regarded Professor of muscle gain research from McMaster University) expects an average person to gain between 4-7lbs (2-3.5kg) of muscle in their first 3 months.

You may also be interested in checking out my other article to learn how many pounds of muscle you can build in 2 years!

Gaining 1-7lbs Of Lean Mass In 3 Months Is A Good Target For Beginners

1-7lbs of muscle gain in 3 months is a realistic target that most beginners can achieve. Most beginners will be able to reach this target even when following a sub-optimal weight gain program. This is because the muscles in an untrained person are highly responsive to training stimuli.

Gaining 1 to 7 pounds of muscle mass in 3 months is likely and a good target for beginners.

Simply put- it’s realistic for you to expect to gain up to 7lbs (3.5kg) in your very first 3 months of training.

That’s because as a complete novice, you have the luxury of benefiting from the “Newbie Gains” period.

Newbie gains describes the ability for beginners to significantly increase muscle and strength in a much shorter time than more experienced trainees.

Elena Popadic, M.S

So just by lifting heavy weights with progressive overload (increasing weight with time) and eating in a calorie surplus, you should be able to build a noticeable amount of muscle.

Gaining 8-9lbs Of Lean Mass In 3 Months Is Unikely But Achievable

8-9lbs of muscle gain in 3 months is a difficult task for most beginners. However, it can be achieved in populations of male high outliers who follow a highly optimized training and diet program. Individuals should be wary that a significant amount of this weight gain can be from fat.

Gaining 8 to 9 pounds of muscle mass in 3 months is unlikely but achievable by certain high outliers.

I managed to gain 10lbs (5kg) in 4 months. You can find out how I did it here.

Accounting for my fat gains, this equated to around 8lbs (4kg) of lean muscle gains in 4 months (or 6lbs in 3 months).

However, this is a period when I was not working and I could dedicate my entire time to training, eating, and optimizing my weight gain program.

So whilst it’s entirely possible, you should just be aware that it takes a lot of work, knowledge, and dedication.

Most beginners who are trying to build muscle in conjunction with a busy lifestyle will probably be unable to reach this goal.

For more details on how long it realistically takes to reach this goal, you may be interested in my other post to find out how long it takes to build 10lbs of muscle naturally.

It’s Extremely Difficult To Gain 10-15lbs Of Lean Mass In 3 Months

10-15lbs of lean muscle gain in 3 months is an extremely difficult task for the majority of beginners. However, very small populations of male high outliers with gifted genetic potential for muscle growth and following a highly optimized weight gain program may be able to achieve this goal.

Gaining 10 to 15 pounds of muscle mass in 3 months is extremely difficult for most people.

Now we’re starting to push the boundaries of the “impossible”.

Whilst there are sporadic claims by people achieving 10-15lbs (5-7.5kg) of muscle gain in 3 months, these are rarely backed by proof.

Furthermore, there’s no scientific research (to the best of my knowledge) that suggests this feat is possible.

It’s Virtually Impossible To Gain Over 20lbs Of Lean Mass In 3 Months

It is impossible to gain over 20lbs of lean muscle mass in 3 months. The muscle-building process is slow. Even with a highly optimized weight gain plan and beneficial genetics, it is unheard of that someone can gain this amount of lean mass in such a short period of time.

Gaining over 20 pounds of muscle mass in 3 months is impssible.


I know we all live in a world of instant gratification.

And we all wish we could pack on this much mass overnight (trust me I’m one of those people too).

But you’ll be hard-pressed to find anyone who can successfully back up their claims of building this much muscle in 3 months.

Nor are there any scientific papers or case studies that indicate this is possible either.

You may be able to gain 20lbs (10kg) in total body weight.

But expect a lot of that to be as stored body fat and water weight.

If your goal is to try to gain weight ASAP (regardless of whether it’s muscle or fat), then you may be interested in my other post to find out how it’s possible to gain 10lbs in a week

5 Factors That Affect Your Real Rate Of Muscle Gains

By now, you should have realized that how many pounds of muscle you can gain in 3 months is highly variable and different from person to person.

Here are 5 of the main factors that influence your real rate of muscle growth:

1) Genetic Potential For Muscle Growth

Everyone has their own natural upper potential limit for muscle growth.

This in turn is affected mainly by your proportion of type II fast-twitch vs type I slow-twitch muscle fibers and anabolic hormone levels (testosterone and growth hormone).

Fast-twitch fibers are those responsible for explosive power and strength generation. They are also the most responsive to hypertrophy (growth).

So if you naturally have a higher proportion of these fibers, you’ll have a higher potential for gaining muscle.

Similarly, some people produce more anabolic hormones than others.

These people will also have a greater potential for quickly packing more mass onto their frame.

Some people also have a greater concentration of muscle stem cells (called satellite cells). These are essentially inactive muscle cells that are waiting to turn into fully-functioning muscle fibers upon training.

So the more muscle stem cells you have, the greater your potential to build muscle.

2) Gender

Men naturally have more lean muscle mass and around 40% more strength compared to women.

That’s mainly due to natural variations in testosterone and growth hormone levels.

So it comes as no surprise that guys can pack on twice more muscle than women.

3) Diet And Nutrient Intake

A “bulk” is key to reaching your full muscle gain potential.

This refers to extended periods of overeating to put yourself into a calorie surplus. These surplus calories are then used to fuel hypertrophy (growth).

Bulking can be “lean” or “dirty”.

I recommend going on a lean bulk to minimize fat gains.

You can do this by eating 5-15% more calories than your daily maintenance calories (which can be determined by the TDEE calculator). This equates roughly to around 18-20 calories per pound of body weight.

Additionally, you should consume at least 1g of protein per pound of bodyweight to ensure a good supply of amino acids (the building blocks for muscle).

Bulking success can be difficult for beginners, and this is one of the biggest culprit reasons why some people gain muscle slower than others.

I recommend a good weight gainer powder to help you reach your nutrition targets successfully, cheaply, and conveniently.

Weight gainer and protein powders can help skinny beginners to quickly bulk up naturally.

The one you see in the above photo is the MyVegan Pea Protein Isolate. Each serving costs $0.30 and contains 100 calories with 21g of protein.

But if you’re completely new to bulking, then the Optimum Nutrition Serious Mass may be better for you since it’s more nutrient-dense

Each serving costs $3 but packs 1250 calories and 50g of protein.

4) Training Program Effectiveness

This is another big culprit for why some people gain muscle slower than others.

A big beginner mistake is to focus on your mirror muscles (chest and arms) and neglect your lower body.

Remember that your lower body constitutes over 50% of your total muscle mass. Furthermore, studies have shown that heavy leg days can increase your testosterone response.

Doing compound lifts like the bench press, shoulder press, row, squat, and deadlift can help skinny beginners to quickly build muscle naturally.

I’m currently using the PowerBlock Elite dumbbells and highly recommend them!

Doing a 3 or 4-day full-body training split is the easiest way to ensure you hit all your muscles. This means you work out 3 or 4 days per week.

It doesn’t matter which days you train, but try to get 1 full rest day between workouts (this won’t be possible on a 4-day split).

I focus on the big 5 compound lifts- bench press, shoulder press, row, squat, and deadlift.

Do 4-5 sets of each exercise per workout, 8-12 repetitions per set, and use a weight that challenges you for those reps.

Rest between sets can be anywhere between 1-3 minutes (depending on your fitness levels).

5) Previous Training Experience

Complete novices will naturally be able to gain muscle at a faster rate than someone who has prior training experience.

This is due to the aforementioned “Newb Gains”.

After your first year of training, you may find that muscle gains slow down to around 1lb (0.5kg) per month. And after 2 years of training, this may fall to 0.5lb (0.25kg) per month.

There is nothing you can do to control this factor, so it’s not worth dwelling on!

You may also be interested in my other guide for 17 essential steps to successfully gaining your first 10lbs of muscle


I’ve explained how much muscle you can realistically expect to gain naturally in 3 months.

Most male beginners can expect to build up to 7lbs (3.5kg) of lean mass in their first 90 days. Females can expect to make half this amount of progress.

But there may also be some outliers who can make even more gains than this.

Ultimately- any beginner can gain muscle in 3 months assuming they follow at least a somewhat acceptable plan.

But how much muscle you actually gain is highly variable and dependent on the 5 factors I detailed in the post!

How much muscle are you aiming to build in your first 3 months of training?

Feel free to send me a message if you have any questions! You can find my details on the “contact us” page.

You may also be interested in the downloadable Kalibre Blueprint PDF which details exactly how I gained 40lbs of lean muscle (it’s 100% free!). It details the exact exercises and nutrition (with printable worksheets) I used to go from skinny to ripped!

Thanks for reading guys!

Peace Out,


(Biochemistry BSc, Biomedical Sciences MSc, Ex-Skinny Guy)


I'm Kal (B.S, M.S)- a health & fitness writer and owner of Kalibre Fitness. I love to nerd out on weight training and nutrition. My primary interests are in muscle hypertrophy mechanisms and strength development. You can connect with me in the "Contact Us" section below!

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