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Everything you NEED to know about the Science & Practice of Muscle Gain

We all want to gain loads of lean muscle, right? Of course. Being muscular looks cool and correlates highly with strength and power. Even better…

…“Strong people are harder to kill.”

Thanks to Mark Rippetoe for that gem.

The problem is that packing on slabs of muscle is HARD! To achieve a lean muscular physique you need to train and eat smart. This article will give you everything you need to know to optimise your training to maximise your muscle building potential.

Winning the Hyper-Trophy

Is this the Hyper-Trophy? Courtesy of che-the-fat.org.uk
Is this the Hyper-Trophy? Courtesy of che-the-fat.org.uk

The scientific term for getting more jacked is muscle hypertrophy. Put simply hypertrophy is an increase in muscular size.

How and why do muscles grow?

Firstly, it is key to understand that there are two types of muscular hypertrophy – Sarcoplasmic and Myofibrillar.

In simple terms these are:

  1. Sarcoplasmic – An increase in volume of the non-contractile elements of tissue which supplies energy to the muscle (aka the sarcoplasm). In layman’s terms…more fluid within cells and a greater capacity to store glycogen.
  2. Myofibrillar – An increase in the volume of the contractile machinery. This involves a growth and multiplication of the myofibrils in the muscle fibre.

It is often said that typical pump-style bodybuilding training leads to sarcoplasmic hypertrophy while low rep strength training (e.g., powerlifters) leads to myofibrillar.

So let’s delve a little deeper into exactly how we can stimulate both of these types of hypertrophy through training.

Here are the most important training parameters (Schoenfeld, 2010):

  1. Mechanical tension: external forces put on the muscles by the weights, resulting in muscle contraction.
  2. Metabolic stress: the accumulation of metabolic byproducts, referred to as metabolites (e.g., lactate, hydrogen ions, and inorganic phosphate) during and following resistance exercise, which indirectly mediate cell and muscle swelling.
  3. Muscle damage: induces a hypertrophic response to repair damage to micro tears accrued from deliberately lifting weights. There is a migration of inflammatory immune cells to help build a bigger muscle.  Usually accompanied by DOMS.

So, to maximize your muscle building potential, you will need to incorporate all three of the above in your training. The best methods to achieve each of these are:

  1. Liftng a heavy load in big compound exercises (squats, chins, rows, bench presses etc.) and getting a significant muscular stretch. Aim to lower the weight under control through a full range of motion to maximise this.
  2. Using higher rep sets with shorter rest periods and intensification techniques such as, drop sets, supersets, rest pause and occlusion training. Cellular swelling (AKA getting da pump!) is the goal if trying to stimulate this pathway.
  3. Eccentric overload training is excellent for this. So using a weight heavier than you can lift and just doing the lowering phase (you will need a spotter for this). An alternative I like for those that train alone is simply emphasise the eccentric portion of the lift. I ask them to try and do the lowering phase of the last rep as slow as possible (10 seconds is a good number to aim for). For example, at the end of the final rep of a set of DB bench press really fight the weight on the way down and lower as slowly as humanly possible.

Now in my opinion 75-80% of your results will come from number 1 (mechanical tension). If you focus on progressively lifting more over time in the big lifts then a lot of your muscle gains will be taken care of. However, to maximise your potential using isolation exercises and techniques aimed at metabolic stress and muscle damage are required.

Manipulating Training Variables – Let’s Go In Depth:

Fibre types:

Type 1, Type IIA, & Type IIB - Courtesy of fitstar.com
Type 1, Type IIA, & Type IIB – Courtesy of fitstar.com

Research indicates that fast twitch fibres have roughly 50% greater growth capacity than slow twitch fibres. As a result, many of us have been sucked into the trap of thinking that we should focus solely on these fast twitch type II fibres to maximize hypertrophy. It makes sense, right? They have a greater capacity for growth so invest all your efforts where you’ll get a big return.

Not so fast (pun intended)!

The above approach is a bit simplistic. After all bodybuilders are the most muscular people on the planet and they do plenty of high rep work. So why are they are bigger than their often stronger powerlifter or weightlifting counterparts?

Firstly, a greater degree of sarcoplasmic hypertrophy but, they also have greater type I fibre hypertrophy. In fact, evidence is emerging that type I fibre can substantially contribute to overall muscle size. Furthermore, it has been shown that low load training can help to maximize type I hypertrophy. So don’t completely neglect training the type I fibres if you want to reach your muscular potential.

Instead use a wide variety of rep ranges. This should predominantly be done at intensities above 60% 1RM to fully stimulate fast-twitch growth. In my opinion, most of your training should be in the 70-85% 1RM (that is 6-12 reps for most people) range when training for size. Performing some training at lighter loads (e.g., 30%), however, can contribute to hypertrophy if taken to concentric failure.

Pump up the volume!

Courtesy of pixgood.com
Courtesy of pixgood.com

For trained individuals performing multiple sets which result in a greater total volume are superior to single sets. It has been found that multiple sets are associated with a 40% greater effect size than single sets.


Well, the sports science geeks best guess is that higher volumes of training may be more effective than low volume training because of the longer duration of tensile force placed upon the muscle. This increased time under tension enhances the potential for microtrauma and to ftigue the full spectrum of muscle fibres. Essentially the muscle is asked to do more work so the magnitude of the adaptation is greater.

Indeed volume is a key determinant of long-term success when it comes to gaining significant muscle mass. So significant in fact that it has been found that performing equivalent volume with heavier weights and sets of 3 reps equate to the same growth as moderate weight used for sets of 10.

The one caveat to the above statement is that performing sets of 10 is a far more efficient way to achieve a high volume of work. Doing so resulted in trainees achieving the same amount of volume as those performing sets of 3 in a third of the time. The moderate weight group also reported less fatigue and a desire to train more while the 3 rep group were borderline over-trained. So from a practical standpoint finding the rep range that allows you to do the most hard (above 60% 1RM) volume per training session is a great idea.

More isn’t better…better is better!

Just because a high training volume is good doesn’t mean you have to go crazy. Muscle gain is a slow process and you need to milk the gains you can make in the long run. Do too much now and you leave yourself with little scope for adding more volume (unless of course you are a pro athlete/bodybuilder who just Eats, Sleeps & Trains!). Make every extra set count…don’t do junk volume!

So how do you set up a sensible and gradual increase in training volume?

A practical approach to increasing your training volume:

  1. Start by selecting 1-3 exercises per bodypart (i’d suggest 1 for small bodyparts)
  2. Train each muscle group 2-3 times a week (generally twice a week for big bodyparts)
  3. Do a total of 40-70 reps per muscle group per session @ >60% of 1RM (make most of it 75-85% 1RM). Start at the lower end of this range and gradually increase.
  4. Perform 2-3 sets per exercise (3 for big compound movements & 2 for isolation work)
  5. Add 1 set per bodypart (not per exercise every 1-2 weeks)
  6. When progress plateaus or even, regresses, de-load for 1 week before gradually increasing training volume back over and above previous maximum

So what is the ideal rep range?

The research currently available is inconclusive but, it does indicate that using a moderate (6-12) rep range for the bulk of your training is best. This rep range is ideal for muscle growth as it allows you to effectively apply mechanical tension, muscle damage and metabolic stress to the working muscle(s). Given these have been established as the three key factors in muscle gain then spending the majority of your time training in a rep range which can achieve all three is optimal.

This rep range is also excellent for achieving a good pump during training. There is increased glycogen storage as a result of getting a pump which in turn attracts more water into the cell. We all know that awesome feeling of getting a skin splitting pump well,  this cell swelling helps muscle growth by inducing a membrane stretch, which signals an anabolic cellular response.

Just because the 6-12 reps are ideal for hypertrophy it doesn’t mean you should never venture outside this rep range. Strength is the “mother quality” and is the foundation upon which maximal muscle growth is built. Training for strength is generally agreed to occur in the 1-5 rep range. Improving your lifts in this range will allow you to create greater levels of mechanical tension. Consequently, it would be a good idea to spend some of your time training for strength if maximal muscle gain is your goal.

One way I like to program this for my clients is include one main indicator lift in each session which you aim to improve the weight lifted overtime. Alternatively, you could incorporate strength work by having dedicated strength/intensification phases in your training periodization. Both strategies work. What suits your preference best is the way to choose what will work best for YOU.

In just the same way that training for strength can have a positive effect on muscular development, training in the higher rep ranges has its benefits. Training with sets of 15-20 reps (perhaps as high as 30 or even 50 with certain exercises) can create a huge amount of metabolic stress (one of the 3 key drivers of muscle growth). Doing training in these rep ranges causes a state of hypoxia (muscle deprived of oxygen) will enhance your ability to buffer lactic acid. As a result, your lactate threshold will improve. This results in you being able to tolerate longer times under tension and do a higher volume of work. High rep sets also create a good pump so you get the benefits of cell swelling and there is a transient rise in anabolic hormones (e.g., testosterone, GH & IGF-1) when training this way. All great for helping to maximize hypertrophy!

(Practical tip: if doing super high rep sets I would suggest you focus on machine based exercises as injury risk is lower on these as fatigue sets in. High rep deadlifts, however, are a recipe for disaster for most people.)

So essentially, there is no single best rep range but, based on the evidence a sensible approach is to do most of your training between 6 and 12 reps. In addition to this, aim to have some training time spent focusing on strength and some devoted to muscular endurance, lactate inducing work.

Training to failure?

Failure can be good but not always!
Failure can be good but not always!

Training to failure all the time is not necessary to cause a hypertrophic response. It does, however, appear that training close to failure is more effective than not. This is likely because a greater number of motor units are recruited and fatigued as sets approach failure.

Training to failure results in high levels of metabolic stress, an acute spike in anabolic hormones BUT constantly training to failure hugely increases your risk of overtraining.

So what does this mean from a practical standpoint?

I would suggest you keep all work sets to within 4 reps of failure, while most sets are more like 2 reps shy of failure. Occasionally, work to complete technical or concentric failure but, not at the expense of overall training volume. By this I mean don’t do your first set as an all-out, balls to the wall effort if it means the rest of your training is compromised.

For example, the first set of 100kg taken to failure at 12 reps might mean that the rest of the sets look like this:

Set 2 100kg x9

Set 3 100kg x7

Set 4 100kg x5

This is a total of 33 reps at 100kg (12+9+7+5) or 3300kg.

Instead doing the following will result in a greater overall volume with less accumulated fatigue (every set wasn’t taken to failure). This leaves you with more in the tank for subsequent exercises.

Set 1 100kg x10 (2 reps in reserve)

Set 2 100g x10

Set 3 100kg x8

Set 4 100kg x7

This equates to a total volume of 3500kg (35 reps total reps).

Training frequency:

The literature appears to indicate that splitting the same training volume into more frequent training sessions is superior for hypertrophy. This is likely because the hypertrophic stimuli are distributed more optimally over the course of the week in higher frequency training approaches. Currently the weight of evidence appears to suggest that training a muscle group 2 times a week is better than once per week. The research is not clear whether training a muscle more often than twice per week is better for muscle growth. As a result, we can conclude (for now) that training a muscle twice a week is suitable for optimizing hypertrophy.

Rest to progress:

Right, now I have your attention I’ll get to the topic of rest periods.

Can correctly managing your rest periods enhance your results? Yes!

Are rest periods the key to maximising your results?

No! BUT, these are possibly the most under utilised variable when it comes to training.

Many people just finish texting before doing the next set. If this is you I think you are missing a trick.

Why do you pay close attention to how much weight is on the bar and how many reps you can do yet, you disregard the length of your rest interval?

Here is a simple rule to follow…rest periods are inversely proportional to reps.

Counter intuitive I know but, if you are looking to increase strength and do a set at your 3RM you should rest 3-5mins before doing another set of that exercise. Conversely, a high rep set will require a shorter rest period of less than 2 minutes (often as little as 45 or even 30 seconds).

Females actually recover faster than men at a given intensity so these rest intervals should be adjusted down for them.

What about different rest periods for different exercises?

Studies have shown that performance in subsequent sets is highly effected by rest period but, also certain exercises are more negatively affected by short rest periods than others. For example, one study found that resting 2 minutes was better than 1 on chest flyes BUT, resting longer (3 or 5-minutes) provided no significant benefit in performance. Conversely, in the bench press resting for longer (3 or 5-minutes) did result in a significant improvement in performance on subsequent sets.

So longer rest periods = more progess?

Well in terms of weight lifted that session yes. Long-term, however, simply extending your rest periods may not be the best approach. To quote Brad Schoenfeld…

“The impact on metabolic stress diminishes with longer rest periods, and this conceivably could have had negatively affected anabolic signaling…Certainly we know that shortening the duration of rest between sets increases metabolic stress, which is known to stimulate muscle remodeling.

And that leads us to what is so often the key…CONTEXT!

Here is a chart to give you an overview of the impact of various rest periods:

Long (3 mins of more) Allows for full recovery of strength but, cause little to know metabolic stress
Medium (60-90s) Causes a high level of metabolic stress, allows almost complete recovery of strength, and results in the peak anabolic response.
Short (45s or less)

Extremeley high metabolic stress, but does not allow recovery of strength.

Ask yourself the following questions:

Where does the exercise fit within the context of your programme? What are you trying to achieve with that exercise at that point in time?

Training a big compound lift which is an indicator of progress? Rest longer (3 or better yet 5 minutes)

Trying to maximize the performance to create high levels of mechanical tension? Then rest longer (3-5 minutes).

Training a smaller isolation movement but want to achieve a high overall workload? Rest longer but, for this movement 2 minutes is probably adequate.

Trying to achieve maximal volume throughout the session? Rest longer (unless time constraints are an issue).

Aiming to achieve hypertrophy through metabolic stress and lactate accumulation? Rest less (60-90s for bigger movements and <60s for smaller &/or isolation work).

So when planning your training don’t just think sets and reps. Use rest to accelerate your gains

Training to gain muscle an overview:

Intensity Mostly 6-12 reps @ 65-85% 1RM
Volume Multiple sets (3-6) for 30-70 reps per bodypart, per session
Exercise Selection Build a foundation on multi-joint exercises, vary movement planes/angles, use isolation exercises to target specific muscle requiring more attention. Select 2-5 (3 in most cases) exercises per muscle
Rest Mostly 60-90s
Frequency Allow 48-72 hours recovery before training a muscle again. Twice a week seems to be the sweet spot
Failure Some sets but NOT all taken to failure. All working sets within 4 reps of failure
Rep speed/tempo Control the eccentric phaase in 2-4 seconds and lift expolsively

You want to get bigger, right?

The desire to be big and ripped is what got most of us into this. The problem is we are all now chasing “dem lean gainz brah!” Unfortunately, you can’t ride two horses with one ass. This is where the principle of specificity comes in.

Pick a goal, focus on that goal, achieve it and then set another one.

Behaviour match goals

So which is it? Big or ripped?

You can have both but, you can’t eat and train for both at the same time. If you do, then they will interfere with the processes that drive muscle growth or fat loss meaning that neither is developed optimally. This is where the myth of lean gainz has let you down.

Ah, lean gainz what a cruel unobtainable mistress you are!

Don’t worry I have fallen victim of this many a time before and it was only once I really started to focus on muscle gain and fat loss as two distinct separate goals (and training phases) that I really saw any significant progress.

So don’t make the mistake I, and so many others have…

…instead dedicate several weeks or months in the pursuit of one distinct goal. Then when required switch focus.

So what is most important right now?

Assuming it is stimulating maximal muscle growth then you are going to need to eat and train accordingly. Cardio will need to be kept to a minimum. Of course cardio has plenty of benefits. It just isn’t a good muscle builder. You don’t need to completely avoid it but, limit the frequency, duration and intensity of it.

Nutrition for Muscle Building – Fuelling the Machine:

As well as training with a hypertrophy focus you’ll need to eat to fuel muscle gain. Many people struggle here and waste all their hard efforts in the gym. If you want to build muscle you NEED to be in a caloric surplus.

Being isocaloric (at maintenance) is sooooo powerless for muscle building that it is pointless.

Sure you’ll accumulate some fat along the way being in a surplus but, the good news is that it is far quicker to drop a few pounds of fat than it is to build pounds of muscle. This means you can diet the fat away ASAP after you’ve finished bulking.

Not sure how to judge progress…?

…” if bodyweight doesn’t change noticeably then nothing happened.”

Simple yet sensible advice from Dr. Mike Israetel

Here are some guidelines to help you effectively measure your progress:

  • Aim to gain 0.250.5kg/week (more accurately 0.25-0.5% of BW/week)
  • Any more than the above means you are likely gaining excessive bodyfat
  • When progress stalls raise calories by 250-500/day (smaller guys closer to 250 and bigger guys closer to 500)
  • Make adjustments based on scale weight rather than some arbitrary weekly adjustment (if weight is increasing by the desired 0.25-0.5% BW/week then adjustments in calories aren’t needed)

Carbs might be your soulmate (or your swole-mate!)

The body’s glycogen levels are linked to muscle growth signalling through a feedback loop. If levels are chronically low, then muscle growth won’t be priority for the body.

Essentially this means gaining appreciable muscle growth on a low carb diet is making life unnecessarily difficult for yourself. I should know I’ve tried. Guess what I hit a long ass plateau with no real size gains.

Do yourself a favour and fuel training sessions and muscle growth by eating sufficient carbs.

As a rule of thumb if you train hard with weights 4-5 days a week consume 1.5g/lbs./BW of carbs per day (weigh 200lbs then eat 300g of carbs). See how progress is. Not gaining? Then bump it up to 2x. If you train multiple times a day you may even need to go as high as 3x.

How Much You Should Eat

What about total calories? Well in my experience you will need to consume at least 16 calories per pound of bodyweight to make good progress. For many this number will need to be in the 18-20 calorie per pound of bodyweight range. I would suggest going higher would be counterproductive for most. You can’t force feed muscle growth and going above this level is likely to result in no extra muscle and the rapid accumulation of fat. Ain’t nobody got time for that!

Courtesy of memecenter.com
Courtesy of memecenter.com

Be your own experiment. Start out with 16 calories per pound? Not gaining weight?… bump it up 17 (then 18, 19, or 20).


Everyone responds differently to a nutrition plan and we are all unique. With that said the following is a great place to start when it comes to setting up your diet.

1g per pound of bodyweight (there are 2.2lbs per KG). So if you weigh 70kg that is 154lbs. As a result, you should eat about 154g of protein per day.

I have found a good starting point for fat is 0.5g/lbs/BW. So our 70kg/154lbs example guy would eat 77g (154 x 0.5) of fat per day.

So if our 154lbs example was starting at 16 calories per pound his total calories would be 2,464 (154 x 16).

We know he is having 616kcals of protein (1g of protein = 4 calories, so 154×4 = 616) and 693kcals of fat (fat is 9 calories per pound, 77 x 9 = 693). So protein and fat combined re 1,309kcals (616 + 693 = 1309).

So that leaves him with 1,155 calories for carbohydrates (2,464 – 1,309 = 1,155).

Carbs, like protein are 4  calories per gram. So simply divide 1,155 by 4 and hey presto, our 70kg friend is having 289g (288.75 to be exact!) of carbohydrates a day.

A quick review:

70kg guy starting bulking diet is as follows:


154g protein

77g fat

289g carbs

Fibre…The 4th macro?

Fibre is often forgotten about. Especially with a few of the IIFYM community. Don’t make this mistake! Simply aim for 10-15g of fibre per 1,000 calories eaten. So for our example that equates to roughly 24-40g of fibre a day.

To conclude this article let’s get a brief overview of the key takeaways:

General recommendations for hypertrophy training:

  1. Two types of hypertrophy:
    1. Sarcoplasmic
    2. Myofibrillar

Want maximal muscle? Train both!

2. There are 3 key drivers of hypertrophy:

  1. Mechanical Tension
  2. Metabolic Stress
  3. Muscle Damage
3. Volume is key!

Gradually aim to do more work. Begin on the low end of what you can recover from. For most this is 15-25 working sets per muscle group per week

4. There isn’t an ideal rep range!

Most training should fall in the 60-85%1RM of the exercise you’re doing. Do not completely ignore strength or strength endurance training though.

5. Frequency:

2 days per muscle group per week – If planning on experimenting with higher frequencies than twice per week begin with smaller muscle groups.

6. Progression:

Aim to do more. You should be able to spend 3-6 weeks of adding about 2% to the weights lifted on big compound movements each week. You can also add volume by adding 1-2 working sets per muscle group each week. When progress stalls or you actually get weaker de-load for a week before re-assessing your goals and setting out on the next phase of training.

7. Fail to plan = plan to fail

Having a periodised plan can ensure you incorporate all the mechanisms of hypertrophy in a sensible structure.

When aiming to gain mass allow 3-4 months of gradual progress. This can be broken down into 3-5 mesosycles.

An example, of how you could set this up from Dr. Mike Israetel is as follows:

1-2 mesocycles of mostly sets of 8-12 reps

1-2 mesocycles of mostly sets of 12-20 reps, with one of those mesoscycles including drop sets, supersets, ultra-high rep sets, and/or occlusion.

Obviously, there is more to hypertrophy than listed above. Little nuances and different ways to refine the process. One of these details is making sure you train individual muscles &/or movements optimally. For more info on the fibre types, volume, frequency, intensity, rep ranges, intenisification techniques, going to failure and best exercises to cause growth in different muscles check back for my upcoming series on the subject of Optimal Muscle Specific Hypertrophy.

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