When it comes to building muscle, many think that the more time you spend in the gym equals the more gains you'll get, but the process of building muscle goes far beyond that.
There's so many benefits to building muscle, but it doesn't come easy. With so many different views circulating the internet, it can be confusing to know where to start, or what approach to training will actually help you.
To bring you the straight facts, we've teamed up with the highly experienced and accredited Exercise Physiologist and personal trainer, Dr Tony Boutagy, to break down the most effective ways to maximise your muscle hypertrophy.
What is hypertrophy
Hypertrophy refers to the increase in the size of muscle fibres, primarily caused by resistance training with progressive overload and consuming enough dietary protein.
A session of lifting weights creates a strong signal in the muscles that were just exercised, which accelerates muscle protein synthesis by increasing the amount of protein stored in the contractile components of a muscle fibre.
The process of growing muscle is slow, as our bodies can typically only synthesise around 30g of new muscle each day.
The benefits to muscle
When most people think of weight training, they look at it purely as an aesthetic endeavour, with the purpose that lifting weights makes our body look better.
But beyond the positive changes in body composition and muscle mass, increasing your skeletal muscle has numerous health benefits too.
Firstly, the amount of muscle mass we have dictates how large our resting energy expenditure is. The more muscle we have, the more energy we burn when we're resting and during exercise.
Secondly, our muscle tissue is the largest reservoir for the disposal of blood glucose after every meal. Maintaining or increasing muscle mass improves our glucose control and metabolic health.
Research has shown that having low levels of skeletal muscle mass and function are strongly associated with a variety of negative health outcomes such as cardiovascular disease, cancer, cognitive decline, and increased risk for disability.
A recent study has also demonstrated that having higher levels of muscle mass and strength were associated with a decrease in hospitalisation time and the severity of illness in COVID-19 patients.
What drives muscle growth
Resistance training causes an immediate spike in the anabolic hormone called testosterone in the growth hormone super family. For many years it was believed that the acute increase in these hormones after exercising ramped up muscle protein synthesis and was the primary driver of muscle hypertrophy.
Recently, more sophisticated research has discovered that this is not the case, and the increase in muscle protein synthesis is almost exclusively a result of the tension placed upon the muscles during exercise.
This is particularly true for volume training, which is a high effort approach to training with repeated exposure to muscle contractions, using multiple sets and exercises.
Training with effort and high volume generates a molecular signal that speeds up the muscle protein synthesis process, and over the long-term, muscle hypertrophy, independent of the acute release of anabolic hormones.
The best training factors to maximise hypertrophy
Effort and failure
When you start a set of resistance exercises, the smallest, slow twitch muscle fibres are initially recruited, as the demand and effort for the first few repetitions is low.
As the duration of the set progresses and your form lessens as you approach failure, then, and only then, are the larger, fast twitch muscle fibres recruited.
The bodies orderly recruitment of muscle fibres, from slow twitch to fast, as the demands of the exercise increases, is called the size principle.
Research has demonstrated that regardless of the repetition range, in order to recruit the maximum amount of muscle tissue, including the fast twitch fibres, a high level of effort must be applied to the working set.
The terms effort, volitional fatigue and failure can all be used to describe what the goal of the set is. You should aim to choose a weight load that does not allow you to perform more repetitions (keeping proper form) than the programmed workout calls for.
Working towards true failure may not be necessary if you're not an advanced trainer with the knowledge to do so safety, but working close to that point is the most effective way to recruit all available muscle fibres.
This is important, as muscle fibres not recruited are not exposed to a stimulus to grow.
To summarise: A high level of effort must be applied to resistance training exercises to maximise the amount of muscle tissue recruited and trained.
Historically, the recommended repetition range for achieving muscle hypertrophy was 8-12 reps. This narrow zone was believed to create the ‘perfect recipe’ for muscle growth, through anabolic hormone release, muscle damage and fibre recruitment.
However, recent studies have now retired this viewpoint, showing that muscle can grow across a wide spectrum of loads, from 8 repetitions up to 30 (or more), considering a high degree of effort is applied to the working set.
At the point of momentary muscular failure, all available muscle fibres are recruited. Studies have shown that failure at 8 repetitions compared to 30 have the potential to create identical muscle hypertrophy, if high effort was applied.
To summarise: The repetition range for muscle growth is much broader than was traditionally assumed. Repetitions between 8 and 30 have the same ability to create muscle growth, given that your sets are performed to (or close to) failure.
The number of sets that are performed for each exercise primarily drives the volume an individual muscle experiences in a session or in a training week.
There is considerable evidence, as you would assume, that a beginner requires less exposure to stimulate muscle growth and an experienced lifter requires more.
Beginners require low set numbers, as the window for positive adaptation is high. For muscle hypertrophy, one to three sets per exercise is a sufficient stimulus to create muscle hypertrophy.
For lifters with over 6 months training experience, greater volume is required, and the recommendation is increased to three to five sets per exercise.
Furthermore, a weekly volume of ten to fifteen sets per muscle group has been identified as the ideal amount (and upper limit of tolerability) for muscle group across a training week. You should aim to include several different exercises that target the same muscle in your workout sessions, and within the training week as a whole.
To summarise: To maximise muscle growth, the sets you choose should be a reflection of your training experience and ability.
Rest time between sets
To create muscle hypertrophy, the two focuses in an effective resistance training program are high effort applied to the working sets, and sufficient training volume, which comes down to set numbers.
The purpose of applying high effort in your sets is to recruit the maximum amount of muscle tissue. If the rest between sets when training the same muscle group is reduced, then the amount of muscle fibres available for recruitment during your following sets is impaired. Any muscle fibres not recruited aren't being exposed to stimulate growth.
Studies have shown that the ideal rest time between sets for muscle growth is two to three minutes.
Studies that compare 60 seconds of rest against 3 minutes rest reveal less muscle growth in the short rest interval group.
The mechanism that causes the blunted response to short rest was recently identified: shorter rest induces considerably higher levels of metabolic acidosis, which was shown to impair the post exercise muscle protein synthesis window.
To summarise: Rest durations of 2 to 3 minutes between sets when working the same muscle group create the greatest stimulus for hypertrophy compared to resting for shorter periods (i.e. 60 seconds or less).
Resistance exercises can be broadly classified as single joint (isolated) or multi joint (compound) movements.
Other ways of looking at exercise selection is based on the number of limbs used (unilateral or bilateral), the method of loading (barbell, dumbbell, machine, body weight, bands etc.) and the range of motion or the stretched position of the muscle during the exercise.
Although there's a lot of debate amongst coaches when it comes to 'the best exercise' for a particular goal, fortunately, for the outcome of hypertrophy, human muscle doesn’t really mind, it simply asks for volume and effort.
If volume and effort are provided on a machine, or with free weights, with one leg or with two legs, muscle doesn’t discriminate. It simply requires effort and volume with whatever the exercise selection is.
Our coaches have long recognised that no one exercise has the best reputation of results. Due to your bodies ability to adapt and get used to certain exercises, a number of exercises should be used across a training year, as each exercise provides unique challenges that can drive effective hypertrophy.
To summarise: There's a number of exercise variations that can be used to train and grow individual muscles. No one exercise is considered ‘the best’, as each movement has its own benefits and limitations that can be used with effect in your training routine.
The Goldilocks Effect - Over or under training
When it comes to creating a training routine, it can feel like a Goldilocks experiment to find the perfect amount of training for your goals, and what's best for your body.
Your exercise sessions is what creates the signal to grow your muscles, but the actual growth takes place during your recovery time between workouts.
Studies into training frequency have shown that a training session designed to increased muscle hypertrophy requires 48 to 72 hours rest between workouts that utilised high effort and volume.
A good rule of thumb is to train each muscle twice a week, which respects the 48–72-hour rule for full muscle recovery.
Many people think of their muscle soreness or DOMS as an indicator for the successfulness of a workout, and often aim for a higher frequency of training, thinking more is better.
Unfortunately, soreness is not a helpful sign to assess your readiness to train, as many signs of adaptation in the muscles cannot actually be felt. This belief leads many people to be over trained and under recovered, which impairs muscle growth.
To summarise: Muscle growth requires both stimulus from your training sessions, and just as important, a period of recovery to make the adaptation. Science indicates that muscles trained with high effort and volume require 48-72 hours rest between workouts. Over-training without adequate rest will take a toll on your results.
Speed of movement
The speed at which we perform a movement is referred to as tempo, which you will read as numbers (such as 2020), below particular exercises in the MWU App.
In the past, this was considered an important variable to consider and manipulate for the goal of training towards muscle hypertrophy.
Newer studies have now shown that tempo is a less important for muscle growth. Rather, the most important consideration is to control the eccentric (lowering) portion of the exercise to stop the effects of gravity.
The lifting, or concentric phase of the movement, should be performed as fast as your body allows while keeping good form.
Resistance training is the most powerful and effective type of exercise to create muscle growth. Over several decades of scientific research, the key elements and variables required for successful hypertrophy programs have been identified as:
- Applying high efforts during the set (working towards muscular failure).
Performing multiple sets of exercises for the same muscle group (1-3 for beginners, 3-5 for experienced lifters).
Hypertrophy can be created across a wide spectrum of repetition ranges, from 8 to 30, which allows for a great deal of variation in programming options.
A weekly volume of 10-15 sets for each muscle group.
Sufficient rest between sets for the same muscle group (2-3 minutes).
A wide selection of exercises should be used to ensure variety in the recruitment patterns.
When the goal is muscle growth, the ideal frequency of training is twice per week per muscle group, to allow for full recovery and adaptation between sessions.
- Using a controlled tempo where you control the lowering speed, stopping the effect of gravity, and lifting as fast as good form allows.
If your goal is to build muscle, you need to understand and apply these key principles to your training, combined with the correct nutrition, to maximise hypertrophy.
If you're ready to take your training to the next level and focus on building lean muscle, strength and overall confidence in your training, our BUILD Challenge is the key to unlock your potential.
Programmed by Rachel Dillon in collaboration with Dr. Tony Boutagy and his principles of hypertrophy outlined above, this 8 Week Challenge includes the most effective weighted and conditioning workouts to maximise your fitness journey.