The Science of Muscle Building – How to Build Bigger Muscles

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By David Thoreau

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How do build bigger muscles? This is a question asked time and time again. The answer however, appears to be different now. Read this article and discover what you need to do to build bigger muscles according the latest research

build bigger muscles

Scientific research is constantly ongoing. This perpetual machine churns out new information, ideas and theories by the thousands every day.

In the context of building muscle, we get some re-evaluations of preconceived ideas every so often – and that’s a good thing. The only problem is, the old idea seems to keep its momentum for a long time after it should have been buried.

Sometimes, the old idea sticks around and overshadows the new one entirely, giving it no room to flourish into the wider populace. The weight lifting and gym community as a whole is particularly susceptible to retention of the ‘old ways’.

Building Muscle – The Old Way

There’s probably several reasons, but the one out in front is probably the old adage ‘nobody likes change.’ Big boys have been doing the same thing for years and it’s been working, so what’s the problem? Right!

Well, maybe they’ve taken a longer route to where they have gotten, because of belligerently hammering away at the less efficient methods. Maybe they got injured more.

Perhaps they actually sneaked in the newer ideas along the way without knowing, and it helped them.

The other reason is ‘bro-science’ – the pseudo-scientific half-knowledge that comes from the experienced, but not necessarily well informed, gym rats. It’s easy to listen to people who look the part, but they don’t always know the best ways.

…and neither do I, by the way. The only thing I can vouch for is that this business is ever-changing, and I try to adapt with it. The articles I write are testament to that. So, I’ll launch right into the first point of discussion, and that is:

lift heavy weight to build bigger muscles

Lifting Big Weights = Bigger Muscle

For the longest time it’s been understood that the way to build big muscle is to lift heavy weights. Sarcoplasmic hypertrophy (size) is predicated on the 10-12 rep sets to ‘almost’ failure – i.e. you really couldn’t lift one god rep at the end.

That means choosing weights that give you that amount of reps exactly before almost failing. It’s roughly about 60% or more of your one rep max weight (1RM).


Lately, research is supporting the theory that lower weights – even as low as 30% of your 1RM – can elicit equal growth response from your muscles. Of course, you’d have to do higher-rep sets, and work to failure the same way every so often but it’s intriguing.

it’s not to say, forget the bigger weight, lower-rep-count sets, but you can definitely include more of those sets and still get the results. There’s some advantages too, like injury prevention and working without a spotter – because you can control smaller weight better.

It’s more about the total work done and the total load shifted. Interesting, no?

Man drinking protein to build bigger muscles

Protein Window – Hit it or Forget Building Muscle

Ah, the anabolic window. I’ve lived by this myself in the past. In the 30 minutes (arbitrary) after a workout, you must ingest some protein…but it might not be that important.

Research shows the more important thing is to keep a steady influx of protein coming from your diet over the course of the day, not necessarily when you take it. And here’s the interesting part: there is a plateau of how much you can actually utilize before you’re just adding pointless calories and wasting money.

The first takeaway point is this: the whole day intake is more important that the ‘anabolic window’ intake.

The second point is this: cramming a lot of protein in one meal doesn’t make that much difference considering you might match your needs for that moment in time with half of that amount.

It’s better to spread it out over the day, thereby using more of it as your body catches up with processing it and putting it to muscle building – which is the whole point anyway!

Man doing cardio

Fasting Cardio Burns More Fat

Okay, if you’re just trying to lose weight, then working out first thing in the morning without eating first might work…sometimes. I definitely would not recommend doing this more than once or twice a week. And, for people trying to pack on muscle, I wouldn’t recommend it at all.

Your body is already likely to be in a state of catabolism (muscle breakdown) because you haven’t eaten anything for hours and it likes to use protein from muscle to keep the energy levels up when you wake.

This is a situation in which people who are trying to build muscle do not want to be. Eating carbs in the morning is how we stop catabolism as it releases one of the principal anabolic activator hormones – insulin.

In fact, first thing in the morning is one of the only times of day I would recommend some fast carbs (high GI, or Glycemic Index), like cantaloupe melon or a white bread bagel.

This example highlights the importance of knowing what your goal is, and going after it. If you are on a muscle drive, don’t mess it up by listening to the bro-scientists at the gym or online and running 5 miles before eating in the morning.

To Summize

In my humble opinion; a little common sense goes a long way. Before all the science started messing with peoples’ minds, there was some simple truths – diet and exercise produce results.

That’s as true today as it was 10,000 years ago, except these days there are quicker ways and slower ways to reach the objective.

At the core of any body composition/physique transformation, there must be 3 things to succeed: Healthy diet, Exercise, and Adequate Rest. Get those 3 things right and the rest is easier.

Bigger, Stronger, and Go For Longer!

We have discussed your motivations, and the reason why muscle mass building doesn’t follow the same training path as strength improvements. We even touched on Sarcoplasmic and Myofibrillar hypertrophy; those being the biological mechanism of tissue growth in and around the muscles.

Now, if we were to throw a third hat into the ring and talk about muscle endurance, we’d better start explaining in more detail about how you put some specificity in to your weight training sessions to optimize your body for size, strength or endurance.

First off, when you think endurance, it probably conjures images of skinny marathon runners. It’s true that endurance weight training will not appreciably build mass or strength, however, there is a place for it in anyone’s schedule, especially those concerned with general heath and fitness.

It helps the body utilize oxygen more efficiently during the stress of exercise – i.e. aerobic conditioning. Endurance in weight lifting is essentially the act of completing sets with higher rep-counts – more than 15 reps as far as the general consensus goes.

In fact, that’s the crux of training specifically for any goal. Rep-count and the amount of weight your lifting are the two main factors involved in turning out Lean, Mean or Machine.

When a guy with huge pecs, hunched shoulders, and tiny legs gives you advice – walk away

Size and Mass Training

There’s a lot of garbage on the internet about getting bigger, and there’s even more garbage coming out the mouths of gym rats who swear by this or that way to get big. When a guy with huge pecs, hunched shoulders, and tiny legs gives you advice – walk away. Similarly, if a guy spends everyday on the squat rack because it’s ‘all about the legs’ then leave him be. Never skip leg day, but who wants to look like two different halves!?

Getting Big is either about aesthetics or it’s early season groundwork before a strength cycle (for athletes), or cut cycle (for bodybuilders). If you train predominantly for size, and you don’t compete, then you are generally doing it to look big and muscly.

Nothing wrong with that, but there’s something you have to remember: training for big pecs, because you like pecs, doesn’t cut it. If ‘BIG’ is truly your objective, then you have to strive for whole body balance.

The same advice holds for anyone doing a bulk cycle for any reason, it’s just more poignant for the vanity lifters!

That means lifting with good form (or technique) and it means hitting all the muscle groups evenly. In fact, if you have an area that seems not to pile on mass like the rest, like shoulders for example, you should put more effort into that area.

So, how much weight should you lift? – That question is answered better by the recommended rep-count. 8-12 reps in a set seems to be the key for mass building.

However, that doesn’t mean you can smoke off 12 reps with a 5 pound dumbbell and expect to look like the Hulk. No, the rep-count is there for a reason. You must choose your weight so that you can just about complete the set before the muscle fails. And the way to choose: trial and error.

We should go back to form quickly. There’s a thing called cheat reps, and there’s a place for them, but it ain’t in this article.

The particular movement you are doing should isolate the muscle or muscle group you are trying to hit. Arching your back, or doing little knee boosts to perform a military press (straight overhead for shoulders), then something is wrong and you won’t get the maximum benefit from you training.

Therefore, size training should respect the following:

  1. 8 to12 reps per set, for 3 to 4 sets.
  2. 60 seconds (smaller muscle groups) to 90 seconds rest between sets
  3. Perform a true set so that you are on the brink of failure at the designated rep-count
  4. Use correct form so that you aren’t hurting yourself or your progress

Strength and Power Training

This is where things get interesting because training specifically for strength is quite different to training for size. The main reason is that strength training should involve more multi-joint movements, for example the big core lifts: deadlift, squat and bench press. Mass builders will do these exercises as well, but for strength the amount of weight goes up.

Higher weight means lower rep-count, that’s just the nature of things. That’s because with more fast-twitch muscle fibres being recruited to complete the set, they will run out of gas quicker too.

Working to near failure or failure (like mass building) is not an option for strength training; there needs to be adequate power left to complete another 4 or 5 sets with the same heavy weight. In addition, rest time between sets can stretch to a few minutes for the bigger movements.

Getting the muscle groups warmed up is mandatory when lifting big. There won’t be any training with a duffed-up back!

Strength training should involve the following:

  1. Small rep-count, ranging from 1-rep-max to about 5 reps, for 4 or 5 sets (no failure)
  2. 2 or 3 or even 4 minutes rest between sets. The bigger the target muscle group, the higher the weight, the longer the rest
  3. High weight: enough that it’s a real effort to pull off the rep-count but not enough to feel near failure
  4. Big movements are at the core of the training; deadlift, squat, bench
  5. Warm up sets essential to build up to the heavier weights
endurance builds muscles

Endurance and Stamina Training

Why on earth would anyone train in a way that doesn’t bring about much in the way of strength or size gains? – Well, muscle stamina has its advantages for anybody who lifts, so incorporating some endurance in your training will go a long way – excuse the pun!

The tactic here is to lift lighter weight for 15, 20, or more reps. The stimulus is not extreme enough to elicit big strength or size increases but it will help your muscles use oxygen more efficiently and train your aerobic engine to go for longer.

It comes in handy as secondary cardio if you aren’t a treadmill/eliptical fanatic, and it will also help your other sessions because you’ll be able to call on your enlarged aerobic reserve to keep you going for longer and recover faster and deeper between sets.

You won’t be maxing out on any lifts, but technique is still important. 25 bodyweight squats can still injure you if done improperly.

Endurance training will check the following boxes:

  1. High rep-count of 15-20 or even more, for 2 to 3 sets
  2. Lower weight, not enough to fail but muscles can be getting sore toward the end.
  3. Good breathing during sets. This isn’t a 1-rep-max deal where you suck down air, hold it in and brace for the lift.

I Want It All, But How?

A lot of fellas will soldier on all year long, beating out massive hypertrophy sets every day, but there’s a reason that can stagnate progress and plateaus are hit, followed quickly by the big wall of zero motivation.

Breaking up your year round activity and integrating the Size – Strength – Endurance methods might improve your results and overall flow.

Everyday cannot be a building day. Your body won’t like it one bit, and besides, you won’t improve. We train to recover, it’s that simple. Each recovery period brings growth, and thus we get stronger, bigger and fitter.

It’s a good idea to use seasons to break up your year. Using the winter to bulk and put the raw material on just makes sense. It’s like slapping the clay on the wheel, to be shaped later on for Summer when aesthetics and practicality necessitates a more defined overall muscle tone.

Two or three big hypertrophy (mass/size) days can be followed by a rest and then a couple of endurance days. Here you will build both mass and some aerobic stamina.

This should make for a good base bulk cycle with adequate recovery. Endurance sets can almost be thought of as active recovery. Or do three weeks of size and one of endurance.

Whatever works and gives you good growth. obviously diet is critical for a quality bulk phase, without making it a fat phase!

During Spring months you can gear it more towards a Strength/Cutting phase, where you increase the weight, decrease the rep-count and throw in a few more cardio sessions. Time it all well and you’ll be looking ship-shape for Summer.

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about the author

David Thoreau is a Biotechnologist with a background in life sciences. He has worked for many years on research projects that have helped people improve their quality of life. David has enjoyed collaborating with other scientists around the world, and he loves sharing his knowledge to help educate others about biotechnology.