How To Build Muscle Fast (According to Science)

We all want to build muscle. 

Muscle mass makes you look better, live longer, increases your strength, and allows you to eat more. 

Building muscle effectively is a goal shared by many fitness enthusiasts, but the sheer volume of conflicting information can make it challenging to know where to start. 

Today, I’ve compiled some evidence-based insights from some of the world’s leading muscle-building scientists to create a comprehensive blueprint for maximizing your gains.

The Basics

Let’s begin with the basics. 

At its core, building muscle is a simple process: you need to lift weights and eat protein. 

When you weight train, your muscles start to think, “If we’re going to keep lifting these heavy weights, I’d better start to get some bigger muscles to make this easier.” 

This is called an adaptive response, similar to how your palms develop calluses when you lift weights.

However, lifting weights isn’t enough on its own. 

To build something, you need building blocks, and when it comes to muscle, these building blocks are called amino acids, which you get by eating protein. 

So, when you lift weights, you’re telling the muscle it needs to get bigger, and when you eat protein, you’re giving the muscle the building blocks it needs to actually grow.

Which Exercises?

Now, let’s dive deeper into exercise selection. 

One of my favorite researchers in the field is Dr. Mike Israetel, a renowned professor of sports physiology (who also happens to be hilarious). 

He recommends using about 2-4 exercises per muscle group per week. 

This approach provides enough variety to target muscles from different angles, but also makes the workouts have enough variety to reduce boredom.

Let’s first talk chest, Dr. Israetel suggests a combination of flat barbell or dumbbell pressing, incline work, and some type of flying movement. 

These should target both the upper and lower fibers of the chest. When it comes to back training, he emphasizes variations of pull-ups (or pulldowns), rows, and deadlifts with strict technique as the core exercises. 

He also recommends flexion rows, where you let your back completely curl over and then arch as you lower the weight, and extend your chest up high at the top as you row, for added back thickness. 

This will target all muscles: the lats, rhomboids, traps, and erectors. 

For biceps, Dr. Israetel advises focusing on exercises that stretch the muscle, such as behind-the-back incline dumbbell curls or cable Bayesian curls (my favorite). 

Triceps training should include a mix of overhead movements, isolation extension work like cable push-downs, and compound pressing exercises.

Shoulder training can be simplified by recognizing that most rear and front deltoid work is accomplished through proper back and chest training, respectively. 

Therefore, the focus should be primarily on side deltoids, with exercises like dumbbell lateral raises, upright rows, and cable laterals.

For legs, Dr. Israetel recommends a variety of exercises. 

Quads can be targeted with high-bar barbell squats, Smith machine squats, leg presses, hack squats, and leg extensions. 

Hamstring training should include hip hinges like stiff-legged deadlifts, as well as a combination of lying and seated leg curls. 

For glutes, he suggests incorporating lunges (particularly with the front foot elevated), hip thrusts, and deep sumo squats.

Calf training, often overlooked, benefits from straight-leg calf raises more than bent-leg variations. 

Dr. Israetel emphasizes the importance of a big stretch at the bottom of the movement, held for 2-4 seconds, before coming up. 

I try to apply these core exercises and their variations in my own and my client’s routines and the proof is in the pudding.

Now that we’ve covered exercise selection, let’s discuss how often you should change your routine. 

Contrary to popular belief, frequently changing exercises can actually hinder progress to a certain degree. 

Dr. Israetel advises sticking with the same exercises as long as you’re getting a good pump, experiencing some soreness, progressing in load and reps, and your joints feel good. 

Only consider changing an exercise if it’s causing joint pain, not producing results, or if you’re simply not enjoying it anymore.

And a caveat – exercises do not necessarily have to be the same EVERY week, they can cycle in and out every few weeks, which is something I like to program for myself. 

How Much Volume and How Often?

Moving on to training volume and frequency, Dr. Brad Schoenfeld, who runs a research lab dedicated to studying muscle growth optimization, recommends a range of 10-20 sets per muscle group per week. 

This range can vary based on individual response and training experience. 

For beginners, the focus should be on learning proper movement patterns rather than immediately going to high volume. 

Dr. Mike Israetel talks about this as well, highlighting recommendations of maintenance volume (MV), minimum effective volume (MEV), maximum adaptive volume (MAV), and maximum recoverable volume (MRV).

Maintenance volume is how much volume you need to maintain your gains. 

Minimum effective volume is the least amount of volume needed to make gains. 

Maximum adaptive volume is the range of volumes in which you make your best gains. 

It’s much more of a range than the other volume landmarks because it changes greatly from week to week. 

Maximum recoverable volume is when the total amount of volume starts to become greater than your recovery and you start impeding your progress. 

I’ll add a chart highlighting them all below. 

Interestingly, research doesn’t consistently show that training a muscle more than once a week leads to better growth, which is contrary to the popular belief held in the last decade. 

However, when weekly volume exceeds the lower ranges of 8 to 12 sets per week, there seems to be a benefit to spreading the work across multiple sessions. 

Dr. Schoenfeld suggests an upper/lower split as a good starting point, which can be customized by adding a full-body workout if more volume is desired.

How Many Reps and How Much Weight?

When it comes to rep ranges and load, Daniel Plin, a former student of Dr. Schoenfeld and researcher at Built With Science, explains that a wide variety of rep ranges can produce similar hypertrophy. 

However, the sweet spot for most exercises and individuals is between 5 and 15 reps, using moderate loads. 

This range balances the benefits of heavier weights with the reduced joint stress and easier failure-proximity gauging of lighter weights. 

Although you CAN build muscle anywhere from 3 to 50 reps per set. 

To ensure continued muscle growth, progressive overload is crucial. 

And increasing either weight or reps can be equally effective for hypertrophy. 

I recommend using a double progression approach: start with a weight you can lift for 8-12 reps, focus on increasing reps with that weight in subsequent workouts, and only increase the weight once you can comfortably perform 12 reps on all sets of an exercise.

Training to Failure

The question of how hard to train – specifically, whether to train to failure – is a contentious one in the fitness community. 

Some like the high volume approach of some influencers, where there are many sets but not all taken to failure. 

Others, like myself, prefer fewer sets with every set taken to failure. Josh and Zach from Data Driven Strength conducted a comprehensive analysis on this topic. 

They found that on average, sets performed about five reps short of failure achieve roughly 75% of maximum potential gains. 

Each rep closer to failure yields approximately 5% more relative growth.

However, while training to failure may lead to more growth in a single set, it also creates more fatigue. 

If this approach compromises your ability to recover between workouts, it may not actually result in more overall growth. For beginners, I recommend you focus on good, safe technique initially. 

As you become more comfortable with exercises, aim to leave 2 reps in reserve for most sets, taking only the last set of each exercise to failure (with the exception of exercises where failure could be dangerous, like heavy squats). 

But feel free to play around with routines with a higher ratio of failure to total sets.

Secret Techniques To Grow Faster

For a potential edge in your muscle-building efforts, there is a new technique making its rounds on social media. 

Jeff Nippard, Dr. Mike Israetel, and all the guys at Stronger by Science have been talking about training at a partial range of motion training at longer muscle lengths, or “lengthened partials.” 

Multiple studies have shown this approach can provide 5-15% faster growth compared to full range of motion training. 

To implement this, try using about half the normal range of motion, focusing on the stretched portion of the movement. 

This technique works well for exercises like lateral raises, bicep curls, tricep push-downs, most back exercises, and chest flies. Incorporating lengthened partials into at 25-50% of your training could give a solid boost in your results.

Rate of Weight Gain

While training is crucial, nutrition plays an even more significant role in muscle growth. 

Dr. Eric Helms, a pro bodybuilder and scientist, explains that while a calorie surplus is often recommended for muscle growth, it’s not always necessary, especially for beginners or those with higher body fat percentages. 

These individuals can often maximize muscle growth at maintenance calories or even in a slight deficit.

For those who are relatively lean and looking to gain muscle, Dr. Helms suggests scaling the rate of weight gain to your experience level. 

Beginners might aim to gain about 2% of their body weight per month (roughly a 300-500 calorie surplus), intermediates around 1% (200-300 calorie surplus), and advanced lifters 0.5-1% (100-200 calorie surplus at most). 

This is a solid rule of thumb to avoid excess fat gain.

What About Protein?

Protein intake is another critical factor in muscle growth. 

The general consensus in the fitness world is consuming 1.6 to 2.2 grams of protein per kilogram of body weight (or 0.7 to 1.0 grams per pound) daily. 

Hitting this target consistently can account for 90-95% of your potential gains from protein intake alone.

For optimal gains, I also want to emphasize the importance of protein distribution throughout the day. 

Research has shown that spreading protein intake evenly across at least three meals per day can lead to greater muscle size and strength gains compared to consuming the same amount of protein in an uneven distribution. 

Keep in mind this is the “optimal” for growth, but what is most important is getting enough consistently and being able to fit it in your lifestyle. 

As for protein sources, a mix of animal and plant-based proteins is probably best. 

Animal sources include beef, fish, poultry, and dairy products like Greek yogurt and whey protein. 

For plant-based options, legumes and beans are excellent choices. 

Interestingly, whole eggs may offer additional benefits beyond just protein content. 

A study by Bugari and colleagues found that consuming three whole eggs post-exercise led to superior changes in body composition compared to egg whites, along with a significant increase in testosterone levels.

How Does Muscle Actually Grow?

I know, reading all of this can be overwhelming on how you can actually incorporate this in your lifestyle. 

I want to delve deeper into the physiological mechanisms driving muscle growth, and hopefully, the explanation will make it more simple by the end of it. 

In 2010, Dr. Brad Schoenfeld published a landmark paper introducing the three-factor model of muscle hypertrophy. 

This model proposed that three main factors drive muscle growth: mechanical tension, muscle damage, and metabolic stress.

Mechanical tension is undisputedly the primary driver of muscle growth within the scientific community. 

It’s the type of force that tries to stretch a muscle fiber, similar to the tension in a tug-of-war rope. 

Tension is passively created when the muscle is stretched and actively created during contraction (like lifting weights).

Muscle damage, once thought to be a significant contributor to muscle growth, is now considered less important. 

While it does occur during training, causing micro-tears and cellular disruptions in the muscle cells, recent research suggests that damage doesn’t correlate well with muscle growth over the long run. 

In fact, excessive damage might even hinder muscle growth.

Metabolic stress, associated with the “pump” feeling during high-rep workouts, was also once thought to be a key driver of muscle growth. 

However, recent studies have shown that the relationship between metabolic stress and muscle growth is not as strong as previously believed. 

For example, shorter rest periods cause more metabolic stress but significantly less muscle growth than longer rest periods.

Given these findings, the consensus is that mechanical tension as the primary driver of muscle growth. 

To maximize tension, you need to apply progressive tension increases to the muscle itself. 

This means lifting with good, consistent technique while using the training variables I mentioned above and progressive overload to push the level of intramuscular tension up over time.

The Deeper Science of Muscle Growth

At the cellular level, the process of muscle growth is complex. 

When you lift a weight heavy enough to create active mechanical tension within the muscle, this stimulus is sensed by something called mechanosensors. 

These sensors then trigger a cascade of events, activating various pathways that ultimately lead to muscle protein synthesis.

One key player in this process is mTOR (mammalian target of rapamycin), a major regulator of cellular growth. 

mTOR is activated via exercise and protein intake. 

When activated, mTOR signals the DNA machinery to produce messenger RNA strands, which serve as blueprints for building new muscle proteins. 

These blueprints are then used by ribosomes to manufacture strings of amino acids.

Through this process, various proteins are synthesized, including the large contractile proteins that make muscles bigger, as well as other proteins that support future growth potential. 

When the rate of protein synthesis exceeds the rate of breakdown, the result is myofibrillar hypertrophy – an increase in muscle fiber size.

It’s worth noting that amino acids from dietary protein also play a role in this process. 

The amino acid leucine, in particular, can activate mTOR independently of mechanical tension. This is why consuming protein in the few hours before and after your workouts can be beneficial for maximizing muscle growth. 

Conclusion

In conclusion, building muscle effectively involves a combination of smart training and proper nutrition. 

Here’s a summary of the key points:

1. Use 2-4 exercises per muscle group per week, focusing on compound movements and exercises that provide a good stretch.
2. Stick with exercises that are producing results and only change when necessary.
3. Aim for 10-20 sets per muscle group per week, adjusting based on your experience and recovery ability.
4. Use a rep range of 5-15 for most exercises, focusing on progressive overload through either weight or rep increases.
5. Train close to failure, but leave about 2 reps in reserve for most sets to balance growth stimulus with recovery.
6. Consider incorporating lengthened partial reps for potentially faster growth.
7. Ensure you’re in a slight calorie surplus if you’re lean and looking to gain muscle, but adjust based on your body fat levels and experience.
8. Consume 1.6-2.2 grams of protein per kilogram of body weight daily, spread evenly across at least three meals.
9. Use a variety of protein sources, including both animal and plant-based options.
10. Focus on maximizing mechanical tension in your muscles through proper form and progressive overload.

Remember, consistency is key in any muscle-building program. 

Stick to your plan, track your progress, and make adjustments as needed. 

With patience and dedication, you’ll be well on your way to achieving your muscle-building goals.

If you’re interested in more tips related to becoming a top tier human, fill out my 1 on 1 coaching application from the button below to become fitter and healthier – guaranteed in 90 days.

All the best,
Dr. Christian