Friday, 23 March 2012

Muscluar Hypertrophy – What is it and How you do it

What is it?
Muscle hypertrophy is an increase in the size of the muscle cells. It differs from muscle hyperplasma, which is the formation of new muscle cells.

The two types of Hypertrophy are Myofibrillar& Sarcoplasmic.

Skeletal muscles are made up of myofibrils which are contractile proteins (basically the fibres that actually generate force) and sarcoplasm which include water, glycogen, minerals, connective tissues, etc.  

There lies a distinction between myofibrillar growth, the growth of the actual contractile fibres which leads to the greatest improvement in athletic performance and sarcoplasmic growth. Sarcoplasmic growth, meaning increases in storage of glycogen, water, etc. does not have a great deal of positive impact on overall performance but there is still physical growth.  This may also be referred as functional hypertrophy vs. non-functional hypertrophy.

How you do it

Myofibrillar and scaroplasmic hypertrophy are not purely individual. Meaning you can’t solely focus on one or the other. Yes certain training protocols may stimulate more myofibrillar growth than scarcoplasmic or vice versa but you don’t get one without the other. 

From now on the topic will be on muscular hypertrophy as a whole. Look at it from the point of view of the lower end of the recommendations being for a greater percentage of scaroplasmic growth and the top end for more myofibrillar growth.

The stimulus for muscle growth falls into three distinct (which overlap each other somewhat) categories: progressive tension overload, muscle damage and metabolic stress.

Each may play some sort of role instimulating the overall growth processes.  It has commonly referred to growth as being related to primarily tension (load on the bar) or fatigue (metabolic stress issues) but damage also appears to be involved.

Studies have suggested that hypertrophy can be stimulated at an optimum degree with a resistance ranging from 60% to 85% of your 1 repetition maximum load weight.  For most people that is the maximum weight use to perform about 5 to 8 repetitions (85%).

Studies that have looked at the volume (work amount) have found to be a higher amount of ‘sets’ have produced maximum training adaptations and stimulated maximal hypertrophy. In subjects that performed either, one, three or eight sets (at 85% of 1RM) showed that 8 sets was superior to 4 and 4 sets were superior to 1.

Meta-analysis reviews on total training volumes have found that a total volume of 30-60 per session (per muscle group) yielded the greatest results in stimulating hypertrophy and training performed twice per week.

Another important factor in training load is the rest time between sets.Rest times have a great impact on the metabolic stress part of the equation (progressive tension overload, muscle damage and metabolic stress).

 Research has shown that there is very little benefit from rest times longer than 2 or 3 minutes. Rest times ranging from 1 minute to 5 minutes have been reviewed and found that strength gains, training adaptations, neuromuscular/fibre recruitment, hormonal  and performance are not significantly better after 3 minutes of rest between sets.

Frequency is the last piece of the puzzle. Most people these days look at training any given muscle group more than once a week as over-training. Well again, research has begged to differ with untrained people gaining most benefits (growth, strength etc) from three times per week for each muscle group and trained individuals having a frequency of twice per week or once every 4-5 days. That also includes the previously mentioned training volumes and loads, which the research was based on for the frequency of training studies.

So summing it all up and what research has found, is by doing each muscle group with a rep range of 5-8 (load of 60% to 85% of 1RM) over 8 sets(which works out to be 40-64 repetitions in a session)with 2 to 3 minutes rest between sets and training each muscle two times per week will be optimum for stimulating muscular hypertrophy and ensure continual progression.

Just as a side note, typically the more highly trained the individual, the higher the work load is needed to stimulate hypertrophy at optimum levels. So beginners will be best suited to using the lower end of the recommendations.

Setting up a routine

So the basics of what stimulates muscular hypertrophy have been discussed and with all of it in mind, now it is up to setting up a routine.

Within the context of the article, doing a 3 day training split would be most suitable. The training split would be broken down into a Push day, Pull day and Legs for maximum and most optimum results, in my opinion. The Push day is made up of Chest, Shoulders and Triceps, the Pull day is Back and Biceps and the final day of Legs is self-explanatory.

Implementing the already outlined information on volume for the routine, it brings me to the point of the smaller/minor/secondary/accessory/assistance muscle groups and the amount of volume and frequency they should be trained. 

Deltoids, Biceps, Triceps, Abdominals (yes they are still made in the kitchen), Hamstrings and Calves are the secondary muscle groups I’m talking about. They are the muscle groups which offer assistance in the core movements of the primary muscle groups of Chest, Back and Quadriceps.

Considering all factors like injury prevention, indirect activation, physical and psychological burn out, training performance and progression the small muscle groups should be trained as frequently as the major muscle groups, but the volume should be less with slightly varying load ranges. Something in the realms of half to 2/3rds of the volume with certain movements being performed in the higher end of the optimal repetition range for hypertrophy.


As it always seems, someone will always take this out of context and not comprehend the article for what it is. This is not for everyone nor is it meant to be so please keep that in mind before you start picking it apart (which is perfectly fine).

This is purely talking about maximising muscular hypertrophy without any outside factors impacting on it. This article was written to de-bunk the typical myths with hypertrophy training etc. I’ve constructed it all from relevant, credible, practical and methodical scientific research and studies on human kinetics and physiology etc.

I’m not factoring in peoples time schedule, lifestyle, training abilities or inabilities, physiological functions, dietary intake and individual goals.They alone determine what amount and type of resistance/hypertrophy training is performed!

 Studies Referenced/Used 


  1. Fantastic article. I'm buzzing with questions which I'm hoping your insights will expand and clarify even more for readers.

  2. So this is like the ultimate for hypertrohpy, if life allowed.
    As you mentioned in Context life determines the upper limits of training since over-training isn't induced soley by training but by total stress.
    Just 3 stressors (say training, work and family) can produce over-training.
    I personally believe I get better results with more rest days but maybe I just have a high stressor count that limits my recovery.

    A note on rest day(s) would expand "Setting up a routine".

    I like the proposed split, as I've been trying several combinations to get the best out of Squats and Deadlifts.
    Is this what you had in mind as minimal example?

    Split 1 Legs: Squat.
    Split 1 Push: Bench Press.
    Split 1 Pull: Chin Ups, Cable Rows, Biceps.
    Split 2 Legs: Deadlift.
    Split 2 Push: Dumbell Press.
    Split 2 Pull: Lat Pulldown, Row Dumbell, Biceps.

  3. Love this blog. Question: as an older recreational lifter whose goal is hypertrophy, I've found trying to go heavy is murder on my joints. My shouders are now starting to ache. I've been doing the 6 reps at 85% 1RM for a while. Would I still make gains if I did 60% 1RM and should I do 15 reps at this weight? According to the online calculators, 60%1RM should = 15RM.

    AND: although data is skimpy, there is at least one study with 30%1RM to failure producing decent protein synthesis. Your opinion greatly appreciated!

  4. Interesting that you see hamstrings as only an 'secondary' muscle group. I would have to suggest an alternative - with the posterior chain (and specifically hams and glutes) needing much more direct work, and being seen as the primary muscle group of the legs / lower body. Not only do they aid in overall balance and symmetry for the aesthetically driven person, but they are fundamental in the development of power & speed, as well as in injury prevention, in the athletic community.

  5. Great thoughts you got there, believe I may possibly try just some of it throughout my daily life.

    Function Point Estimation Training