Editor’s Note: This post was updated on April 26, 2018 for accuracy and comprehensiveness. It was originally published on September 19, 2017.
by InBody USA
If you’ve ever tried to lose weight before, you may have heard that a 3,500 calorie deficit results in about one pound of fat loss. In other words, if your daily caloric requirement is 2,500 calories and you spend seven days eating just 2,000 calories, you’re likely to lose around one pound of fat.
But, there’s no rule of thumb explaining how to put on (or lose) a pound of muscle mass.
Because it’s not a simple equation. Unlike losing fat, putting on muscle isn’t as easy as causing a calorie surplus. You need to know how muscle building works so you can set realistic goals, especially if you’re participating in a fitness challenge. This article will lay out factors that go into your “gains” and will answer the question: “How much muscle can you realistically gain in one month?”
The Three Pillars of Muscle Growth
Building muscle comes down to three inputs: nutrition, exercise, and hormones. Understanding these factors is the first step toward understanding how much you can build in one month.
The term nutrition is defined as “the process of providing or obtaining the food necessary for health and growth.” At a fundamental level, muscle growth starts with the nutrients you put into your body.
People trying to gain muscle generally eat a high protein diet. After all, the amino acids that make up protein are the building blocks of muscle. Your body can manufacture many of those amino acids, but nine are known as essential amino acids (EAA) because they can’t be made in the body. Instead, you have to consume EAAs from food sources like meat, beans, nuts, and soy. A diet containing mixed amino acids can help maximize muscle protein synthesis.
The amino acid, leucine is responsible for many of the anabolic (muscle-building) processes. This is known as the “leucine trigger concept,” since sufficient quantities of leucine trigger muscle protein synthesis.
Protein is not the only macronutrient responsible for muscle growth. In fact, there appears to be a limit to the amount of protein one can consume to maximize muscle gain. Additionally, it takes energy to build muscle, and this means you need a positive caloric balance in order to achieve hypertrophy.
If you want to build muscle, increase your dietary protein intake– but don’t exclude your carbs and your fats. Carbs and fats aren’t all bad for you! All three are important, thus a diet balanced in carbs, protein, and fats is effective for gaining muscle.
But remember, it’s not just the calories. Physical activity is also key to promoting muscle development.
2. RESISTANCE EXERCISE
Workouts that include resistance exercise stress the muscles, which results in muscle gain.
Your body adapts to resistance exercise by growing or changing to make them more capable of handling the workout.
The stress of resistance exercise causes the muscle fibers to tear at the cellular level. Then, special muscle cells called satellite cells jump into action to repair, rebuild, and grow the muscle.
The right types of exercises, like high-intensity workouts or compound exercises, can promote increased muscle growth. A healthy balance between workouts and rest is necessary to support healthy hormone levels and maximize muscle gain.
Three primary hormones that stimulate muscle hypertrophy are insulin-like growth factor 1 (IGF-1), growth hormone (GH), and testosterone.
After weight training, increases in these hormones correspond with muscle protein synthesis, one of the key processes in muscle hypertrophy.
Essentially, these hormones signal to the muscle that it’s time to repair and build up after a session in the gym. GH is released in the greatest quantities during sleep, so remember that getting a good sleep helps you attain your body composition goals.
When nutrition, workouts, and hormonal effects combine, the muscle-building magic really happens. Figuring out the right balance is essential for reaching your goals.
How to Manage Your Muscle Gains
Your body’s individual response to nutrition, resistance exercise and hormones can vary. But other factors can impact how much muscle gain in a month.
Supplementing Muscle Growth
Muscles need the right fuel to grow. Protein supplements are long known to boost help muscle hypertrophy, and fueling your body with EAAs is important for providing the nutrients your body can’t synthesize.
After weight training, consuming protein stimulates muscle protein synthesis by supplying providing amino acid building blocks. Traditionally, 20 grams of protein has been considered enough. Researchers recently found that experienced lifters doing whole-body workouts may need about 40 grams. But consuming more than approximately 1.6 grams per kg of body weight per day has no additional benefit for building muscle. Excess protein is burned for energy like carbohydrates and fats, excreted in urine, or even stored as fat.
Timing could also be important: research shows intaking protein before bed during a resistance training program is especially helpful for building muscle mass.
Note: While supplements may be beneficial for promoting muscle recovery and growth, they are only effective when combined with a balanced diet and exercise plan. More on supplements and their effects can be found here.
So what should you expect?
Just like muscle can’t turn into fat, fat can’t turn into muscle.
It is unlikely that your body will be able to utilize all of the additional calories for muscle growth. Some of the caloric surplus needed to gain muscle is going to be stored as fat, and that’s OK.
Only the most stringent of diet and exercise protocols have been shown to result in simultaneous muscle gain and fat loss. Researchers have called this protocol “grueling and unsustainable”, so it’s probably not an ideal strategy.
If you want to gain muscle, you need to accept that you’ll probably have some slight fat mass gain. It’s just being realistic.
What if you’ve hit a plateau?
Gaining muscle mass is all about forcing the muscle to adapt to novel stress. It’s no surprise that gains come more readily to novices than experienced weightlifters. For novice lifters, the right weight training program should be enough novel stimulus in the gym. Recent research suggests hypertrophy can be measured in as little as one month. But, there seems to be an upper limit to muscle gain. Experienced lifters should be closer to that ceiling than novices, making their incremental gains smaller.
How can the experienced weight lifter overcome this challenge? By introducing different and new nutritional or resistance stimuli.
The principle is simple: change up your routine. Since trained muscles adapt to consistent stimuli, adding variation will challenge the muscles in a different way and promote further growth.
The muscles you train also dictate your potential to gain. Your arms have a much lower total potential to gain muscle than your hips and legs because they’re smaller muscle groups.
Don’t skip your upper body lifts just yet, though. Research shows that arm muscles may be quicker to hypertrophy than legs. The ceiling is lower, but the rate of gain relative to what’s already there is quicker.
What if you’re not as young as you used to be?
Older adults may have a harder time building muscle because the body’s response to weight training has diminished. The muscle building machinery is still there, but it may require more input to achieve desired results.
To overcome this hurdle, use ‘novel stimulus’ thinking from the previous section. Try consuming some extra protein or adding a few new exercises to your routine. The goal is to convince your body to adapt to what you’re throwing at it.
Building muscle may be harder than it was in your youth, but it can still be done.
So what’s a realistic expectation for muscle growth for men vs.women?
It’s time to estimate how much you can reasonably gain in one month. It can be very frustrating seeing a man have an easier time putting on muscle. Due to the different physiological makeup of men and women, we will discuss hypertrophy separately.
THE FACTS FOR MEN
Remember that study we referenced earlier? The goal was simple: lose fat while packing on muscle. It worked – participants gained about 2.6 lbs (1.2 kg) of lean body mass and lost fat mass – but it was totally unsustainable. The cornerstone of this program was daily heavy circuit training, HIIT and sprint-interval workouts, and plyometric workouts, all while restricting calorie intake to just 60% of daily requirements and taking in high doses of protein supplements.
A word of caution: don’t try this program at home.
What you can take away is that those men, who had never lifted weights before, gained over 1 kg of lean body mass in just one month.
Another group of researchers decided to try a more sustainable program on a smaller scale, and guess what? The men gained 4 kg of skeletal muscle in 16 weeks. That means the rate of muscle gain was almost identical to the grueling, unsustainable program – about 1 kg per month.
This program, consisting of just five exercises (squat, knee extension, knee flexion, bench press, and lat pull-down), was certainly more realistic.
Based on the research, it’s reasonable to expect untrained men to be able to gain about 1 kg, or 2.2 lbs, of muscle per month at the beginning of an exercise program.
But what about experienced weightlifters? Because experienced lifters will likely have a slower rate of progression, the amount of gain will be generally lesser and depend on the level of training experience of the individual.
THE FACTS FOR WOMEN
Women tend to be less muscular than men, and most people believe it’s harder to build muscle as a female. There’s some truth to that statement. Muscle hypertrophies in proportion to the baseline quantity of muscle mass, so women gain less muscle mass than men because their baseline muscle mass tends to be lower.
How much muscle gain is typical for young women? One study says about 0.5 – 0.7 kg in the first month for novice weightlifters. This study involved just two lifts – the squat and the deadlift. You might be left wondering what happens when women undergo a whole-body weightlifting program.
Women’s arms gain muscle at about 3 times the rate as legs (an increase of 9.7% in arms vs. 3.3% in legs). According to the study, women can expect to increase their muscle mass by 1.5 kg during the 20 weeks of training, averaging out to 0.3 kg per month.
Since body composition wasn’t measured at any point during the 20 weeks of training, there’s no way of knowing whether the participants increased muscle mass faster in the first month or two.
So is that the end of the discussion? Not exactly. Remember, each individual is different and not everyone will be able to sustain a consistent diet and exercise routine to promote muscle development for extended periods of time. This is why research on this topic is more scarce than you might think. Many researchers measure muscle hypertrophy by looking at changes in the circumference around limbs or by imaging cross-sections of the body. This allows them to understand muscle growth in different body segments (arms, trunk, legs).
However, newer technology, such as Direct Segmental Multi-frequency Bioelectrical Impedance Analysis (DSM-BIA), provides a quicker, less invasive way of measuring muscle mass in addition to other components of the body.
Altering your body composition is no easy feat. It takes patience, effort, and commitment, but it’s definitely within your reach.
Your body primarily needs three basic stimuli to build muscle: nutrition, resistance exercise, and hormones. You can and should manipulate nutritional and exercise stimuli to keep your body responding.
If your current daily protein intake is 0.8 g / kg of body weight, try bumping that up to 1.5 g / kg if your doctor says it’s okay. If you currently lift twice per week, try gradually increasing to three or four sessions per week. And if you don’t do resistance exercise at all, it’s time to start!
Some people will gain substantially more, and some will gain less muscle over the course of a month. But in general, the average is about 1 kg for males and 0.5 kg for females.
To have the best chance of building muscle, stick to a training, nutrition, and recovery plan. Make sure you get your body composition measured to set a baseline and track your progress to figure out whether your fitness regimen is working for you. If you don’t meet the average values mentioned above in the first month, use the next month as an opportunity to change your routine.
Armed with the tips and realistic expectations from this article, you’ll be on your way to a better body composition in no time.
Max Gaitán, MEd is an exercise physiologist and a USA Triathlon Certified Coach. When he’s not coaching, studying, or writing, Max spends most of his time outdoors training for triathlons.