How long does it take to build muscle? That’s a difficult question to answer, because there’s no single correct answer that will apply to all people, all of the time.
The length of time it takes to build muscle depends on how much muscle you’re talking about and who’s doing the building.
Nobody can tell you exactly how long it’s going to take to build muscle, because they don’t know.
That’s because muscle growth varies so much from person to person that it’s almost impossible to predict in advance exactly how much muscle you’ll gain over a given period of time.
However, what I can do is give you a rough idea about the sort of results you can expect to see after weeks, months and years of training.
Knowing approximately how long it takes to build muscle will stop you wasting time, effort and money running around in search of some magic pill, diet or training program that’s making promises it can’t deliver.
How Quickly Can You Build Muscle?
For the average guy, it’ll take 3-4 months to gain around 10 pounds of muscle. However, that number assumes all the muscle-building stars are aligned. By that, I mean that you’re new to lifting weights, training hard 3-5 days a week, eating enough food and getting all the protein your muscles need to recover and grow.
You’re also in your twenties with all the hormonal advantages that go with it, a relatively low-stress lifestyle, and getting 8-9 hours of sound, restful sleep each night. You have the discipline to eat right and train hard on a consistent basis, week in and week out, for months at a time.
Keep in mind that results will vary from person to person. Some folks, despite training hard and eating right, will gain closer to 3 or 4 pounds over the same period of time.
Others will make faster gains. In one study there were a few individuals who saw stand-out results, adding around 15 pounds (6.8 kilograms) of muscle in 12 weeks .
In another, a group of untrained beginners gained, on average, 12 pounds (5.6 kilograms) of muscle after 10 weeks of weight training .
What if conditions are less than optimal? What if you’re in your forties, short on sleep and your diet isn’t all that it could be?
If so, the results will come more slowly, and you’ll need to scale back your expectations accordingly.
The length of time it takes for a muscle to grow is also affected by whether you’re building that muscle from scratch, or re-building muscle that’s been lost.
Re-building muscle that you’ve had in the past, but subsequently lost, happens more quickly than gaining it in the first place. That’s because of a phenomenon known as muscle memory.
When a muscle is gained, lost and then gained back again, it will grow more quickly during the re-building phase compared to the initial training period from an untrained state .
Muscle tissue itself can’t actually “remember” anything. Rather, the number of nuclei in muscle cells increases when you lift weights.
But those nuclei aren’t lost when you stop training and your muscles shrink. Instead, the extra nuclei form a type of muscle memory that allows the muscle to bounce back quickly when you start training again.
“When you start training, your muscle cells get bigger and develop more nuclei,” explains Sweat Science author Alex Hutchinson.
“When you stop training your muscle cells get smaller again, but the extra nuclei persist long after training stops. Then, when you start training again, the nuclei are still there, ready to support re-expansion of the muscles.”
All other things being equal, if you’ve been in shape before, your muscles will grow a lot faster than someone who’s starting from scratch.
No matter how long it takes you to gain muscle, it won’t be too long before the law of diminishing returns kicks in.
Everything happens quickly when you’re just starting out. But you won’t keep building muscle at the same rate indefinitely, and your results are going to slow down over time.
In other words, the first 10 pounds of muscle might come in four months or less. The next 10 pounds might take eight months. Adding another ten pounds might happen a lot more slowly, over a period of maybe 2-3 years.
That’s because there is a “ceiling of adaptation” or “upper limit” of what you’re capable of in terms of muscle growth. The closer you are to this upper limit, the slower the gains will come.
In your first year of serious training, you can realistically expect to build anywhere between 10 and 25 pounds of muscle.
Under the right conditions, guys with a large bone structure and good genetics may see gains of up to 25 pounds, while smaller men with less favorable genetics will find that 10 pounds is about the limit.
However, those gains aren’t going to come at a steady pace throughout the year. Most of your progress will be made in the first 3-6 months, and slow down over time.
In year two, we can cut those numbers in half, giving you a gain of 5-12 pounds. In year three, the gains will be halved again, giving you 3-6 pounds of new muscle.
You can certainly gain weight at a faster rate, as the addition of fat and water weight will add a few more pounds (maybe a lot more depending on how relaxed you are with your diet). But if it’s just muscle growth you’re talking about, those numbers are roughly where the natural limits lie.
Can Anyone Build Muscle?
Anyone can build muscle. However, not everyone can build muscle at the same speed. Some lucky folks put on muscle relatively quickly when they start lifting weights. For others, the results come much more slowly, even if they lift and eat the same.
The figure below comes from a study where a group of guys with a similar build, age, and training history lifted weights for 12 weeks [4, 5].
When the researchers looked at the results of the men who built the most muscle and those who built the least muscle, they found roughly four times greater gains in muscle in the fast versus the slow responders.
To put it another way, you and a friend of a similar build could follow exactly the same training program and diet for the next three months.
But individual variations in the rate of muscle growth mean that he might gain eight pounds of muscle. You, on the other hand, could gain just two pounds.
Research also shows a wide range of strength gains even in people following identical training programs .
Subjects were grouped into fast (those who made greater than 20% strength gains), medium (10-19% gains) and slow responders (less than 10% gains).
There was an average increase in strength of 29% for fast responders, 14% for medium responders and 3% for the slow responders.
In other words, some people respond extremely well to strength training. Some will get “good but not great” results. Others will respond a lot more slowly.
There are genetic factors outside your control that affect how long it takes to build muscle, as well as the maximum amount of muscle you can expect to gain naturally. And unless you’re willing to have your genes tampered with by a renegade scientist, there’s not a single thing you, me or anyone else can do about it.
How Long Does It Take To See Muscle Growth?
The process of building muscle begins almost immediately after your first workout . Just three hours after training, muscle protein synthesis is already ramped up. Your body is busy repairing damaged muscle fibers, as well as laying down the new muscle protein that makes each fiber bigger than it was before .
To give you an idea of the time course of changes in muscle thickness over time, check out the figure below.
It comes from a team of Japanese researchers, who took a group of untrained men, and got them to do nothing but the bench press three times a week for six months . Every week, they used ultrasound scans to assess changes in muscle thickness in the chest, triceps and biceps.
As you can see, there was a small increase in muscle size from week to week. Those gains were small, and flattened out over time. But the pecs and triceps were still growing on a regular basis.
Don’t be discouraged if progress seems slow. It takes a while for short-term changes in protein synthesis to show up as actual changes in muscle mass, and you may not notice those changes for several weeks or even months.
On a related note, it’s worth pointing out that gains in strength will outstrip gains in size when you first start lifting weights. You’ll get stronger far more quickly than you gain muscle. That’s because not all of those strength gains are driven by an increase in muscle size.
Rather, your neuromuscular system, the “chain of command” that transmits signals from the brain to the muscle, is doing a better job of using the available fibers in a given muscle. The fact you’re getting stronger doesn’t mean that muscle is being built at an equivalent rate.
Doubling the amount of weight you’re able to lift in a given exercise doesn’t mean that the muscles involved in lifting that weight have doubled in size. Nor does it follow that increasing the size of a muscle by 100% will produce an equal gain in strength.
How Many Times a Week Should You Go to the Gym to Build Muscle?
To maximize muscle growth, you should go to the gym at least twice a week. Three times a week will be better. And, if you’ve got the time, four workouts a week is better than three. Ideally, you want to train each muscle group at least twice a week.
Training a muscle just once a week can and will make that muscle bigger. However, the research out there shows that, for most people at least, it’s probably the least effective way to train.
When a team of scientists reviewed several studies that investigated training a muscle once, twice or three times a week, they concluded that “the major muscle groups should be trained at least twice a week” to maximize growth .
One of the key driving forces behind muscle growth is muscle protein synthesis, which refers to the creation of new muscle protein. And it’s the gradual accumulation of this new muscle protein that makes your muscles bigger .
After you train, protein synthesis goes up. But it’s back to normal a couple of days later . In other words, when you train a muscle once a week, it might spend a few days “growing” after the workout. But leaving seven days before you train that muscle again means missing out on several additional opportunities to stimulate growth.
How Much Muscle Can You Gain in a Month?
Assuming their training program and diet are set up properly, the typical beginner can expect to gain somewhere between 2 and 4 pounds of muscle in their first month of training.
Contrary to the claims of some, you’re not going to gain 30 pounds of muscle in 28 days. It doesn’t matter how many supplements you’re using, what special foods you’re eating or how much training you’re doing. It’s not going to happen.
Even Arnold Schwarzenegger, who combined great genetics and a Herculean work ethic with more than a little pharmaceutical assistance, was very happy when he gained 25 pounds in weight over a 12-month period.
Here’s what he wrote in Arnold: The Education of a Bodybuilder:
“Many people regret having to serve in the Army. But it was not a waste of time for me. When I came out I weighed 225 pounds. I’d gone from 200 to 225. Up to that time, this was the biggest change I’d ever made in a single year.”
So if one of the greatest bodybuilders in history is saying that 25 pounds was as much as he ever gained in one year (and not all of this was muscle), there’s no way that a drug-free, genetically average guy can expect to do the same thing in a fraction of the time.
Building shirt-straining muscle takes a long time. Most people will need to train for somewhere between 3 and 5 years before they get anywhere close to their physical limits as far as muscle size is concerned.
That’s 3-5 years of hard work, proper training and good nutrition. It’s not something you can do in 30 days, 12 weeks or even 12 months.
SEE ALSO: THE MUSCLE BUILDING CHEAT SHEET
If you're fed up spending hours in the gym with nothing to show for it, then check out The Muscle Building Cheat Sheet.
It's a "cut the waffle and just tell me what to do” PDF that tells you exactly how to go about building muscle. To get a copy of the cheat sheet sent to you, please click or tap here to enter your email address.
ABOUT THE AUTHORChristian Finn is the nation’s leading authority on science-based, joint-friendly ways to build muscle. A former "trainer to the trainers," he holds a masters degree in exercise science, and has been featured in or contributed to major media on two continents, including the BBC and Sunday Times in the U.K. and Men’s Health and Men’s Fitness in the U.S.