Updated: May 11
A common misconception among gym goers, especially the less experienced, is that 3 sets of 10 repetitions for each exercise are enough for muscular development. Well, if it was that simple gyms would be full of Greek statues, there are many more factors to consider. When we talk about programming an exercise plan, the most important factors are: volume, intensity and frequency.
Three inseparable variables
Volume, intensity and frequency are three interconnected and inseparable variables that influence each other. Eric Helms, scientist and bodybuilder, places all of them at the same level of his Strength Training Pyramid. If we look at the training frequency for example, we will notice that a high frequency corresponds to a fatigue increase, therefore, a reduction in volume and intensity will be necessary in order to not affect the performance and prevent overuse injuries.
The Prilepin’s table below is a good starting point for determining the volume and intensity of strength training:
However, clarification is needed. Prilepin’s table is an outdated method that does not consider individual skills and abilities, does not show recovery times between sets and the different intensity levels within the same training session either. Also, it only focuses on the same load for each session. Furthermore, the Prilepin’s table was created for weightlifters who perform exercises such as snatch, clean and jerk, and power clean, i.e. exercises without negative phase that require more explosive power than the general gym activity.
The Prilepin’s table is just one of many methods used to establish the optimal level of intensity and volume, and should not be seen as an absolute rule. For example, Sheiko, a famous Powerlifting coach, has created a method based on the weekly tonnage, but there are also many others based on self-regulation such as the Russian Bear, the Canadian Bear and the Myo Rep. However, these methods do not provide a precise idea of optimal training volume and intensity either.
Two recent meta-analyses report that the optimal range of sets to train a movement for strength gains is 5-12+ sets per week, while 10+ sets per week is the optimal amount for hypertrophy (muscle mass gain). However, to date, there are not enough studies about the limit of volume. Some authors report that training a movement for more than 20 sets per week is not productive. However, it must be clarified that these meta-analyses consider the average sport individual; looking at the studies carried out on athletes, the reported results are different and a greater volume (30+ series per week) is still beneficial for these subjects.
However, the contribution of volume to strength improvement is less than the one provided by the training intensity. A workout that focuses more on heavy loads is more efficient for strength improvement, but if both load and volume are high, fatigue, joint pain and injury risk increase as well. To maintain the same volume, the best thing to do is mixing light and moderate loads. Helms et al. (2018) recommend performing 2/3 - 3/4 of the volume in a range of 1-6 repetitions at 5-10 RPE (Perceived Effort) and the remaining 1/3 - 1/4 at moderate intensity in a range of 6 -15 reps at 5-10 RPE.
To get the most out of strength training, loads should increase over time. However, after a while this approach no longer works and an increase in volume training (at the expense of recovery time) may be necessary to progress further. Therefore, the right training volume should be planned according to the athlete’s needs and his "Training Age" (i.e. the training time experience).
The latest data shows that a multi-frequency training method is preferable to train strength.
Multi-frequency means training one, or more muscle groups, several times a week. This approach, nicknamed "Greasing to the groove" by Western trainers, contrasts with the mono-frequency method where the training of a movement and muscle group is performed only once a week.
A meta-analysis of 13 studies about the effects of training frequency reports that higher frequency is associated with greater strength gains. The same results were reported by other studies as well although the training volumes were different.
Muscle hypertrophy should be considered as well. The meta-analyses show that training each muscle group at a higher frequency, regardless of volume, results in greater hypertrophy. Muscle size contributes to 30% of athletic performance. The force exerted by a muscle fiber is directly proportional to its cross-sectional area (CSA), therefore, increasing CSA size leads to strength improvement. However, strength does not depend on hypertrophy only and other factors such as neuromuscular adaptations, motor patterns and metabolic factors must be considered when planning a training plan.
Principle of Individuality
Looking at the results of so many studies, it might feel "safe" to say that “a high training frequency leads to greater hypertrophy and strength gains”. Unfortunately, it is not that simple. Indeed, Nuckols reminds us that these results are not applicable to athletes as individuals, because science deals with averages: a very interesting concept that underlines the importance of the principle of individuality.
If you want to learn more about these topics, I suggest reading the book “Muscle and Strength Pyramid - Training” by Dr. Helms.
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