Driving Muscular Hypertrophy
Before we consider the many facets of Hypertrophy-Specific Training (HST), let’s first consider muscular hypertrophy itself. Hypertrophy is a word that is often thrown around in the health and fitness sector and, while many recognize that it refers to muscular growth, few understand the true demands and requirements necessary to bring about changes in muscle mass.
HST is a training method based on a number of well-researched scientific principles that were first discovered in the laboratory. Over the years, these methods have been refined and adjusted to coincide with the latest research and are seen as essential for all hypertrophy training. An effective HST program will incorporate the following principles in order to elicit maximal muscle growth.
The 4 Muscular Hypertrophy Principles
There are 4 primary principles that are considered foundational for all hypertrophy training. Over time, providing that these principles are applied appropriately, individual muscle fibers will be forced to adapt and grow in cylindrical size leading to an overall increase in total mass.
1. Mechanical Load
The first principle to consider is quite an evident one; it is the application of mechanical load. Mechanical load is the driving force for hypertrophy and appears to be the most important principle for stimulating muscle fibers to grow. Research indicates that muscles are stimulated to grow after being exposed to a certain degree of mechanical loading. This load can be applied through the use of barbells, dumbbells, kettlebells, resistance machines, and even your own bodyweight.
This mechanism involves a number of cellular processes and responses involving satellite cells, growth factors, calcium, and an array of other well-researched factors connected with muscle tissue strain (1). It’s important to recognize that it is not the effort required to lift the weight that causes adaptation to occur. Rather, it is the physical effects of placing a load on the muscle as it moves through concentric and eccentric phases that dictate change. Additionally, it’s important to recognize that building muscular fatigue does not dictate the rate of muscular growth. This, therefore, means that you do not necessarily have to work through to absolute muscle failure in order to stimulate significant growth.
2. Chronic Stimuli for Growth
As stated, muscles will only be stimulated to change after being subject to a certain degree of load. If we fail to regularly expose the muscles to a training stimulus, we fail to see substantial changes in muscle mass. It is essential to create the right environment for maximizing muscle growth; this is something that can be done through manipulating training frequency…
While we must train frequently to elicit growth, the general consensus is to allow for at least 48 hours before training the same muscle group again – this principle is applied with HST. It has been suggested that training any sooner than 48 hours may even hinder and impair protein synthesis and consequent muscular growth (2). The purpose of repeatedly loading the same muscle group every 48 hours is to maintain a high anabolic state and encourage maximal muscular growth.
While some may argue that 48 hours is not a long enough recovery period, research suggests that although the muscles may not have fully recovered structurally, exercising 48 hours later will not negatively impact the muscles recovery ability.
3. Progressive Load
As your muscles are exposed to a training stimulus, significant strength, neural and metabolic adaptations will take place. Initially, the stimulus applied to the muscles is new and in order to deal with the demands of the training, the muscles must adapt. However, if you continue training at the same intensity, you will quickly reach a point where your muscles will no longer adapt or increase in size. This is because they have adapted to the point that they can cope with the training stimulus.
This is why it is essential to apply the progressive load principle to our training. Progressive loading involves gradually increasing the demands of training – typically through manipulating a training principle such as intensity, volume or load. In simpler terms, we can progressively load our training by gradually adding more weight on the bar or by adding additional reps and sets into our workouts (3).
With HST, you will progressively load on a week by week, session by session basis. The goal is always to add more weight with each completed session. If applied correctly, you will continue to provide an effective training stimulus to the muscles thus facilitating muscular growth.
4. Strategic Deconditioning
This principle is the one hypertrophy principle that is most commonly overlooked however, it is vital for efficient progress. The reason that the deconditioning principle is often avoided is that it involves halting all training for a short period of time. On the face of it, a week off may be welcome however, many individuals fail to schedule in deconditioning periods believing them to be unnecessary.
Strategic deconditioning is simply the opposite of progressive overload. Its purpose is to reduce training intensity which allows the body time to recover from previous exertions thus priming the muscles for future growth. As stated, the principle involves a short period of time of no training (typically lasting one to two weeks). A deconditioning period should be applied as soon as improvements are seen to stall. The purpose of this is to allow the muscle to detrain to a certain extent and allow it to become sensitive to the training stimulus once again (4).
Finally, It’s important not to confuse strategic deconditioning and deloading. While the purpose behind both methods is similar, they are applied slightly differently. As mentioned, strategic deconditioning involves a total cessation in all resistance-based activity whereas deloading allows resistance training to continue but at a reduced intensity.
HST Guidelines
Although HST follows these universally recognized principles, HST programs do tend to look slightly different from others. The reason for this is that there are a number of specific guidelines that must be followed with all HST programs – guidelines that are based on scientific studies and backed up with years of research.
HST vs Conventional Training
The first apparent difference between HST and other hypertrophy programs is in regards to training volume. In order to stay true to hypertrophy principles, sets of heavy lifts are spread out through the week, rather than just one bout per week. For example, if there are 6 prescribed sets of squats, instead of completing the entire six in one sitting, the sets are spread out across the course of the week. So, instead of completing the full 6 sets of squats on Monday, as with many conventional programs, you perform 2 sets of squats on Monday, Wednesday and Friday.
This method allows you to apply the training stimulus to the muscle group multiple times per week. In doing so, you promote hypertrophy all while reducing the demand on the nervous system thus reducing the risk of overtraining. Additionally, there are a number of studies which suggest that performing multiple sets may not have a significant impact on hypertrophy and therefore, 1-2 sets will suffice. (5).
While the volume for individual exercises may be low, the total weekly volume for HST is average and actually comparable to universally used “split” hypertrophy programs.
Exercise Choice
For HST, and hypertrophy training generally, it is important to select heavy, compound exercises to provide the most potent training stimulus possible to a number of muscle groups. Compound exercises are movements which demand effort from a muscles groups across a number of joints. A few excellent examples of effective muscle-building compound exercises include squats, bench press, bent rows, and shoulder presses.
Isolation exercises, where the focus is on developing a single muscle group, can play a supplementary role in hypertrophy training, however, as stated, the main focus should predominantly be on compound movements.
Adjusting Reps
HST involves decreasing the number of reps performed every two weeks – starting with 15 reps for the first two weeks and gradually working down to sets of 10 and 5. This is done to accommodate a gradually increasing load as the weeks progress.
It is possible to adjust the rep range on a weekly basis (15, 12, 10, 8, 5), however, whether you adjust reps on a weekly or fortnightly basis has no impact on the rate of adaptation.
Building Fatigue and Lactic Acid
As with many hypertrophy orientated strength programs, HST incorporates high-rep sets. The intention with high-rep sets is to build lactic acid levels to increase the readiness of the muscles and connective tissues for dealing with heavy loads. This will not only work to reduce the risk of sustaining an injury but may promote healing and general health of tendons.
Eccentric Training
One final difference between HST and standard hypertrophy program is the inclusion of a two-week block of eccentric training. As you may already be aware, in order to produce movement, muscles must contract concentrically and eccentrically. Concentric contractions involve the shortening of muscles whereas eccentric contractions lengthen the muscle.
Eccentric training focuses on the lengthening of muscles under a load. For example, let’s analyze the bicep curl. In order to drive the bar upward toward the shoulder, the biceps must concentrically contract followed by an eccentric contraction in order to lower the bar back down to the hips. To complete eccentric bicep curls, this lowering phase must be accentuated with the contraction taking 3 – 5 seconds to complete.
Eccentric training has been thoroughly researched over the years and what is clear is that eccentrics are stronger than concentric contractions and can, therefore, tolerate a greater deal of strain (6). Based on this, HST recommends that you perform eccentrics using more than your 5 rep max to increase the mechanical load on the muscle and contribute toward greater muscular hypertrophy.
HST Summary
– Train each muscle group every 48 hours
– Look to increase the weight lifted with every workout
– Decrease the number of reps every 2 weeks (15, 10, 5)
– Add a 2-week block of eccentrics at the end of the training cycle, if necessary
– Allow for Strategic Deconditioning, when appropriate
Sample HST Program
The following tables include a sample from a general HST program. You will find week 1 and week 2 workouts displayed below.
Week 1
| Day 1 (Monday) | Day 2 (Wednesday) | Day 3 (Friday) |
| Back Squat 2 x 15 |
Leg Press 2 x 15 |
Back Squat 2 x 15 |
| Leg Curl 2 x 15 |
Leg Curl 2 x 15 |
Leg Curl 2 x 15 |
| Bench Press 2 x 15 |
Dips 2 x 15 |
Bench Press 2 x 15 |
| Chin-Ups 2 x 15 |
Bent Rows 2 x 15 |
Chin-Ups 2 x 15 |
| Shoulder Press 2 x 15 |
Shoulder Press 2 x 15 |
Shoulder Press 2 x 15 |
| Shrugs 2 x 15 |
Shrugs 2 x 15 |
Shrugs 2 x 15 |
| Bicep Curls 2 x 15 |
Bicep Curls 2 x 15 |
Bicep Curls 2 x 15 |
| Tricep Press 2 x 15 |
Tricep Press 2 x 15 |
Tricep Press 2 x 15 |
| Calf Raises 2 x 15 |
Calf Raises 2 x 15 |
Calf Raises 2 x 15 |
Week 2
| Day 1 (Monday) | Day 2 (Wednesday) | Day 3 (Friday) |
| Leg Press 2 x 15 |
Back Squat 2 x 15 |
Leg Press 2 x 15 |
| Leg Curl 2 x 15 |
Leg Curl 2 x 15 |
Leg Curl 2 x 15 |
| Dips 2 x 15 |
Bench Press 2 x 15 |
Dips 2 x 15 |
| Bent Rows 2 x 15 |
Chin-Ups 2 x 15 |
Bent Rows 2 x 15 |
| Shoulder Press 2 x 15 |
Shoulder Press 2 x 15 |
Shoulder Press 2 x 15 |
| Shrugs 2 x 15 |
Shrugs 2 x 15 |
Shrugs 2 x 15 |
| Bicep Curls 2 x 15 |
Bicep Curls 2 x 15 |
Bicep Curls 2 x 15 |
| Tricep Press 2 x 15 |
Tricep Press 2 x 15 |
Tricep Press 2 x 15 |
| Calf Raises 2 x 15 |
Calf Raises 2 x 15 |
Calf Raises 2 x 15 |
Final Word
Many hold HST in extremely high regard as it has been found to be very effectual for building significant muscular size. It appears to be an extremely powerful muscle building method and as a result, HST has been adopted by a number of competitive bodybuilders. While HST is a method worth adopting for bodybuilders, over the years it has also proved to be very useful for athletes and participants across a number of sports – specifically, powerlifters and Olympic lifters.
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References:
1- The Journal of Strength and Conditioning Research 24(10):2857-72 · October 2010
2- Tipton, K. D.; Wolfe, R. R. (2001-3). “Exercise, protein metabolism, and muscle growth”. International Journal of Sport Nutrition and Exercise Metabolism. 11 (1): 109–132. ISSN 1526-484X. PMID 11255140.
3- Services, Department of Health & Human. “Resistance training – health benefits”. www.betterhealth.vic.gov.au.
4- Häkkinen, K.; Komi, P. V. (1983). “Electromyographic changes during strength training and detraining”. Medicine and Science in Sports and Exercise. 15 (6): 455–460. ISSN 0195-9131. PMID 6656553.
5- Carpinelli, R. N.; Otto, R. M. (1998-8). “Strength training. Single versus multiple sets”. Sports Medicine (Auckland, N.Z.). 26 (2): 73–84. doi:10.2165/00007256-199826020-00002. ISSN 0112-1642. PMID 9777681
6- Hoppeler, Hans (November 16, 2016). “Moderate Load Eccentric Exercise; A Distinct Novel Training Modality”. Frontiers in Physiology. 7. doi:10.3389/fphys.2016.00483. ISSN 1664-042X. PMC PMCPMC5110564