Sarcoplasmic hypertrophy focuses more on increasing muscle glycogen storage capability (and thus the size of the muscle) where myofibrillar hypertrophy focuses more on increased myofibril (muscle fiber) size. Heavier weights (close to maximal loads) at a lower volume produce greater gains in myofibril size while more moderate weights at higher reps promote sarcoplasmic gains.
Hypertrophy Specific Training (HST) is a training methodology with the primary focus on increasing the size of the muscle through sarcoplasmic hypertrophy.
When looking into the science behind muscle growth, it becomes clear that bro-science and bro-training traditions like “body part splits” and “blasting” muscles are not based on any kind of science. This doesn’t mean they don’t work, but if you’re trying to come up with a training program based on the science vs. “bodybuilding tradition,” your approach will probably be different.
When looking at the research, a very interesting picture forms of how muscle fibers translate mechanical strain into the signals that:
A) allow them to grow and, as a consequence
B) make them more resistant to said strain
The size of a muscle fiber is linked to the number of nuclei it contains. In order to make muscles grow over the long term, you must strain the component muscle fibers in such a way that you get nearby satellite cells to differentiate and donate their nuclei to those muscle fibers. The frequency of stimulus seems to make a very large difference on the magnitude of growth. What this means is exposing a muscle more frequently to weights seems to be very effective when it comes to making them grow.
There is research which compare 9 sets of a given exercise done once a week to 3 sets performed 3 times a week with otherwise identical parameters. This compares one big stimulus a week to a smaller stimulus performed more frequently, yet with the same total weekly volume. In these studies, the three times a week routine consistently outperforms the once a week routine in terms of muscle growth.
The basis of HST is that given the option of performing X amount of workload in a given week (weight X sets X reps), you’re better off spreading that workload over 2-3 sessions than lumping it into one big “blasting” session. There are some other parameters concerning “strategic de-conditioning”, which is de-loading in the sense of trying to re-sensitize muscle tissue to the growth stimulus.
A good, basic HST set-up might be done 3x a week and look like:
- A vertical push exercise (overhead press of some type)
- A vertical pull exercise (like chin-ups, pull-ups or pull-downs)
- A horizontal push (bench press or variant)
- A horizontal pull (seat row, bent over row, or some sort of rowing variant)
- Any extra isolation work you to add in for lagging body parts (curls for biceps, calf work, flyes for chest, laterals for shoulders, etc….)
For reps, consider the following schedule:
- Weeks 1-2: 15 reps per exercise
- Weeks 3-4: 10 reps per exercise
- Weeks 5-6: 5 reps per exercise
- Week 7: 1 week off for novice to intermediate
- Week 8: off for advanced
- Restart cycle
Effort should be close to maximal in order to complete the prescribed number of reps.
When it comes to volume:
- 2 sets of each exercise during the 15s
- 3 sets of each exercise during the 10s
- 3 sets of each exercise during the 5s
A lower volume version would be 1 set during the 15s, 2 sets during the 10s, 3 sets during the 5s.
The time off is an important part of HST training theory is predicated on time off between cycles, so make sure you have at a minimum 1 week of time totally off doing resistance training between cycles.
If you’ve been lifting for longer, I’d recommend 2 full weeks off from heavy weights between cycles.