3 Factors to Muscle Growth


So you want to build some muscle aye?

It’s a common goal for a lot of lifters out there.

Whether you’ve been hitting the weights for 5, 10, or many more years, or you are just starting out, packing on some size can be as desirable as a glass of cold water in the middle of the Sahara Desert.

But what should your approach be?  You can…

A) Follow the buff dude at the gym

B) Try and figure it out on your own


C) Follow a plan based on SCIENCE and RESEARCH

The first one might sound good at first but consider these things…

  • The buff dude at the gym has probably been working out a lot longer than you have and has progressed his workload; what he’s doing now is not what he was doing in the beginning.

  • He probably has a lot better genetics than you do and his body is able to go through protein synthesis more often and more efficiently.

  • He probably has a much better mind-to-muscle connection than you do and is able to contract his entire leg complex when standing up from the toilet.

  • And he could be using anabolic assistance so don’t get unrealistic expectations and expect yourself to look like he does if you are planning on staying natural.

The second option, trying to figure it out on your own, can be good for a little while but eventually, you may find yourself wore out, plateaued, and maybe even injured.

For myself, I always found it useful to admit that I DON’T know everything and I can always learn from others who are smarter than me and who have researched and tested their claims backed up by science.

Upon writing this blog I read Brad Schoenfeld’s, The Mechanisms of Muscle Hypertrophy & Their Application to Resistance Training peer-reviewed research paper.

All of my facts come from that document and I’m not in school anymore so I don’t have to cite something if I don’t want to!   Just search on Google if you want to find the paper.  Or wait one sec… just… click… HERE!

Schoenfeld put together this famous and comprehensive research paper to:

(a) extensively review the literature as to the mechanisms of muscle hypertrophy and their application to exercise training and (b) draw conclusions from the research as to the optimal protocol for maximizing muscle growth.  -His words

And in my words… The research was done because… We want to know how to get HUGE!

Mechanical Tension

Mechanical tension is considered essential to muscular growth.

Tension does not necessarily mean weight; you can still create a ton of tension within a muscle even without weight.

The guy at the gym using his hips and shoulders to swing up a 70lb dumbbell to curl may be using a lot of weight for the exercise but isn’t really creating a lot of tension.

Tension is created in the muscle through force and eccentric stretching of the muscle.

If you are benching and stopping at the top to lock out your elbows, your joints are stacked and you are no longer creating a lot of tension.  If you want the tension to continue during this exercise then start lowering the bar before reaching the lockout point at the top.

You may be squatting 500lbs but instead of lowering the weight under control you decide to bring it down as fast as you can, bounce right back up and rest at the top.

In this case, you would be better off taking some weight off so you can control the eccentric; (the negative/lowering portion of the lift) contract your glutes, quads, and hamstrings while explosively pushing the ground away from you as you stand up to complete each rep.

This will allow you to keep tension in the muscles you want to work.

Tension should be kept in the working muscle until the end of the set.

Muscle Damage

Muscular damage occurs as a muscle is broken down and exhausted during exercise.

The muscle can become inflamed and damage is done to its connective tissue.

This is a normal response to exercise.

During an eccentric stretch of an exercise, the muscle is under a lot of force generated stress and the muscle begins to break down.

Think of finishing an incline dumbbell bicep curl by lowering the weight to the bottom again.  Your arms are fully extended at the bottom of the lift, triceps contracted, biceps lengthened, and with the dumbbells still in hand… try holding that for 30 seconds after a set.

This creates a ton of tension and eccentric stretching of the biceps and is likely to cause some temporary muscular damage.

Blood is rushed to the muscle, trauma is created in the muscle, and after the workout, the body begins to heal itself.

Damaged muscles could stimulate satellite cell activity, leading to muscular hypertrophy aka growth.

Metabolic Stress

Metabolic stress results from exercise that relies on anaerobic glycolysis for ATP production.

Think of “The Pump” developed from high rep sets.

Muscle ischemia (inadequate blood supply to a muscle) can result in metabolic stress and can lead to muscular hypertrophy.

When a muscle is under tension during a long exercise set metabolites such as lactic acid and creatine phosphate build up in the muscle causing metabolic stress.

Metabolic stress is not considered essential to growth but can be a complementing factor.

Other Factors Relating to Muscular Growth


Insulin-like growth factor is considered to be the most important mammalian anabolic hormone and can be found in satellite cells in the body.

It promotes anabolism and increases the rate of protein synthesis thus leading to growth.


Testosterone is a hormone derived from cholesterol and has an anabolic effect on muscle tissue.

The effects of testosterone are magnified in the presence of mechanical loading.  This increases the rate of protein synthesis and decreases muscle atrophy (breakdown of muscle).

It can also stimulate the release of growth hormones and satellite cells which are linked to muscular growth.

Growth Hormone.

Growth hormone is secreted by the pituitary gland and can have anabolic and catabolic effects while inducing the metabolization of fat.

The greatest amounts of growth hormone are released after intense exercise and during sleep while the body is recovering.

Growth hormone released as a result of exercise is highly correlated with the hypertrophy of type I and type II muscle fibers.

Cell Swelling.

Cell swelling (cellular hydration) results from increased pressure against the cell membrane that leads to the body reinforcing its infrastructure.

It is most present during exercises that result in a large build-up of lactic acid.

Since cell swelling increases protein synthesis and decreases proteolysis (the breakdown of protein into amino acids by enzymes) it has an anabolic effect on the muscles involved.


Hypoxia is the deficiency in the amount of oxygen present in a muscle.

Occlusion training is the blockage or closing of blood vessels used by a muscle.  One way to do this is wrapping a tight band around the top of the bicep just below the deltoid while doing curls… this results in hypoxia.

Hypoxia can lead to muscle gains.


Muscular growth doesn’t come from any one thing in particular but from the accumulation of many different variables.

Mechanical tension, muscular damage, and metabolic stress work synergistically to maximize muscular hypertrophy.

The body doesn’t understand weight, it understands tension.

Tension needs to be created within a muscle in order for it to grow and get stronger.

Think about pushing the ground away from you as you stand during a squat, pull from your elbows during a row, and contract your biceps before initiating a curl; all of these will help to create tension.

The muscle needs to be broken down in order to be built back up.

Spend time in the lengthened (eccentric) portion of exercises to maximize muscle stretching and muscle breakdown.

Chase the pump during exercise; allow your muscles to go through longer sets to build up lactic acid.

When your muscles start to burn during a set, try to extend the set as long as possible to maximize metabolic stress.

Training within all of these variables will help to maximize muscular growth which is what we are all after after all right?

Get out there and GROW!  

Kyle Wilkinson