In a recent study, subjects trained one leg with standardised training volume (the same volume for everyone), and one leg with individualised volume (a 20% increase above their prior baseline).
Individualised volume led to more quad growth, suggesting that we should be more concerned about manipulating training volume based on your recent history, rather than aiming to find one single “optimal” level of training volume for everyone.
Lets dig in.
Over eight weeks, trained subjects trained one leg with 20% more weekly sets than they’d been using in their training previously, and trained the other leg with 22 sets per week, regardless of prior training volume.
Subjects experienced significantly more quad growth, on average, in the leg that underwent a 20% volume increase, even though average volume ended up being similar between conditions.
When assigning training volume, it’s better to focus on gradually increasing volume from one’s current baseline, rather than simply jumping to some level of volume that’s theoretically ideal for the average person.
This study represents an important piece of the puzzle that’s been sorely missing from the resistance training literature. When studying the effects of training volume on muscle growth, subjects tend to be assigned to differing volume conditions without any regard for prior training history.
If a study uses 10 sets per week as a low-volume condition and 20 sets per week as a high-volume condition, the 10-set condition may feel like super high volume and be very difficult to recover from for someone who had previously been training with a volume of just 5 sets per week for the target muscle group; on the other hand, 20 sets per week could feel like a deload for someone accustomed to 30 sets per week.
There’s one more thing I’d like to clear up about the results of the current study: We know that a 20% increase in training volume above the subjects’ pre-training baseline worked well, but we can’t claim (as the authors of the study do) that a 20% increase in training volume “maximises muscle hypertrophic response in trained individuals.”
There’s only one way we could ascertain the optimal (average) increase in training volume to maximise hypertrophy: We would need a study to compare different volume increases. If a study tested increases of, say, 10%, 20%, and 30%, and 20% came out on top, then we could claim that, on average, a ~20% increase in volume maximises hypertrophy over a matter of months.
Slightly increasing your training volume above its current level will probably help you build more muscle, as long as you aren’t already straining your ability to recover from and adapt positively to training. Theoretically, cycling training volume over fairly long time scales (e.g. multiple months) may lead to more muscle growth than sticking with a fixed level of training volume over time.