Summary of Realities of Resistance Training Volume and Muscle Hypertrophy
- The authors conclusively state that the relationship between training volume and muscle hypertrophy in trained individuals is not as straightforward as previously believed.
- Transitioning to empirical evidence, it’s observed that similar muscle growth occurs in both lower and higher-volume training protocols. This boldly contradicts the idea that increased volume invariably leads to more growth.
- The magnitude of muscle growth in some studies raises questions about the generalizability of the findings. For example, it may be common to observe a 0.1-0.25 cm increase in quadriceps muscle thickness following an intervention. However, studies have observed changes as high as 0.6-0.72 cm in quadriceps muscle thickness.
- Emphasizing the need for personalization considering individual differences in muscle growth, a more tailored approach to resistance training is strongly recommended.
Introduction to Muscle Hypertrophy
The quest for muscle hypertrophy is a cornerstone of fitness regimes for bodybuilders and gym enthusiasts alike. Scientists and bodybuilding coaches have a never-ending battle about the best approach. In bodybuilding, it seems like a real-life Star Wars battle is occurring. Some believe that adding more sets is favorable to muscle growth. We will call them the good side or the Jedi (i.e., believe more sets is a more conducive approach to gaining muscle). They believe that increasing training volume is the key to muscle gain. (Schoenfeld et al., 2019; Schoenfeld et al., 2017a, 2017b) Conversely, the dark side believes that adding more volume or sets will not result in more muscle growth. (Heaselgrave et al., 2019; Ostrowski et al., 1997)
Sets and Muscle Hypertrophy: Incorporating New Insights into Resistance Training Literature
Incorporating recent findings is crucial for advancing the knowledge of resistance training. The review’s novel perspectives offer potential avenues for updating the existing literature on resistance training volume, particularly in relation to muscle hypertrophy. Emphasizing the significance of integrating new evidence and advocating for a discourse update, the review’s insights are pivotal for enhancing the understanding of resistance training volume and its impact on muscle hypertrophy. This push for incorporating new evidence aligns with the objectives of advancing the scientific discussion on resistance training.
The optimal training volume for maximizing these adaptations remains a topic of debate. A recent review recommends 12-20 weekly sets per muscle group, which may be an optimum standard for increasing muscle hypertrophy in young, trained men. (Baz-Valle et al., 2022) Their findings shed light on the impact of training volume on muscle hypertrophy, highlighting the need for further exploration in this area. However, a new review of the literature titled “The dose-response relationship between resistance training volume and muscle hypertrophy: There are still doubts” challenges this notion that adding more sets is the key to gaining muscle, suggesting a more nuanced understanding of muscle growth. (Buckner et al., 2023) This article is going to summarize the key findings of the review.
Is There a Linear Response to Sets and Muscle Hypertrophy?
The review mentions a notable publication, “Evidence-Based Guidelines for Resistance Training Volume to Maximize Muscle Hypertrophy,” which posited that higher training volumes are a primary driver of hypertrophy, leading to greater muscle growth. (Schoenfeld & Grgic, 2018) However, this assertion that more volume is the key driver of muscle growth is now under scrutiny, as previous studies reveal a more complex picture.
Scientific Discussion on Training Volume and Muscle Hypertrophy
The new review is a comprehensive review of literature that questions the extent of the dose-response relationship between training volume and muscle hypertrophy. It highlights that the evidence for the impact of resistance training volume on hypertrophy in trained individuals is more ambiguous than clear. The review points out that several studies have observed similar muscle growth between lower and higher-volume training protocols, challenging the traditional belief in the linear relationship between volume and hypertrophy.
Examining Specific Studies Involving Sets and Muscle Growth
Heaselgrave et al. (2019): This study examined changes in biceps brachii muscle thickness (MT) over 6 weeks with varying training volumes. The results showed minimal differences in MT changes across low (9 sets), moderate (18 sets), and high-volume groups 927 sets), suggesting that higher training volumes did not confer additional benefits.
Ostrowski et al. (1997): This research focused on muscle size changes in the rectus femoris and triceps brachii over 10 weeks of varying training volumes (3, 6, and 12 sets per muscle group per week). Like Heaselgrave et al., no significant differences were found between the groups, indicating that higher weekly volumes did not yield additional muscle growth advantages.
(Amirthalingam et al., 2017): This study investigated the effects of a modified German Volume Training Program on muscular hypertrophy and strength. The regular training group performed 5 sets of 10 repetitions for the major lifts) versus a relatively higher volume training program (10 sets of 10 repetitions for the major lifts). The results did not demonstrate significant increases in muscle mass as measured by B-mode ultrasound in either the low or high-volume groups at any of the muscle sites imaged.
(Aube et al., 2022): The study examined the impact of different training volumes—12, 18, and 24 weekly sets—over 8 weeks. For the anterior thigh muscle thickness, the highest responses were observed in the 12-weekly set group, with an increase of 0.38 cm (6.4%). The 24-weekly set group showed the lowest responses, with an increase of only 0.15 cm (2.7%) despite performing double the number of exercise sets compared to the 12-set group. The Aube study’s results suggest that performing a higher number of weekly sets may not always lead to proportionally greater muscle growth, challenging some common assumptions in resistance training literature.
Methodological Considerations and Potential Explanations of Sets and Muscle Hypertrophy
The review suggests that the discrepancies in muscle growth observed in various studies could be attributed to methodological differences, such as training and ultrasound methods or interface selection in ultrasound imaging. Additionally, the possibility of swelling being mistaken for muscle growth in high-volume training protocols has been raised. While swelling typically dissipates within 48-72 hours post-training, it may be more pronounced in high-volume training scenarios, potentially skewing results. (Buckner et al., 2017)
For example, the article also refers to a study comparing long and short rest intervals, where the long rest interval group showed significantly greater muscle growth. However, there were no statistically significant differences in the volume of work performed between the groups, nor significant correlations between total load volume and changes in muscle measurements.(Schoenfeld et al., 2016) Furthermore, Camargo et al. (2023) highlighted that some studies that observed an enhanced hypertrophic response following an increased volume (number of sets) approach did not consider the previous volume performed by each participant in their usual training routine before the commencement of the experimental period, indicating that the relationship between training volume and muscle hypertrophy may be influenced by individual training history. (Camargo et al., 2023)
Current Perspective on Training Volume
Despite the evidence suggesting that higher training volumes can lead to greater muscle growth, the magnitude of growth observed in some studies is unusually large, raising questions about the generalizability of these findings. This ambiguity in the current evidence suggests that while training volume is an important factor in hypertrophic response, its exact role and significance might be more complex than previously thought. The current recommendations may overstate its importance, necessitating a more cautious interpretation of these findings and further replication of studies. The authors said, “While there appears to be some threshold of volume that is necessary for muscle growth, the current recommendations may exaggerate its importance.”
Conclusions on Sets and Muscle Hypertrophy
In conclusion, while resistance training volume is undoubtedly a key factor in muscle hypertrophy, the relationship is not as straightforward as once believed. This nuanced understanding calls for a more individualized approach to resistance training, considering the variability in responses among different individuals. The fitness community is encouraged to consider these complexities when designing training programs, ensuring a balanced approach that goes beyond the simplistic notion of ‘more volume equals more growth.’
In a manner reminiscent of the concluding scenes of a Star Wars epic, where balance is restored to the Force, this review suggests a harmonious balance in resistance training. Just as the Jedi seek equilibrium between the light and dark sides of the Force, trainers, and athletes should strive for a balanced training volume that aligns with individual needs and goals rather than adhering to a one-size-fits-all approach. In the end, the path to muscle hypertrophy, much like the journey of a Jedi, is personal, nuanced, and filled with discoveries that go beyond conventional wisdom.
References
Amirthalingam, T., Mavros, Y., Wilson, G. C., Clarke, J. L., Mitchell, L., & Hackett, D. A. (2017). Effects of a Modified German Volume Training Program on Muscular Hypertrophy and Strength. J Strength Cond Res, 31(11), 3109-3119. https://doi.org/10.1519/jsc.0000000000001747
Aube, D., Wadhi, T., Rauch, J., Anand, A., Barakat, C., Pearson, J., Bradshaw, J., Zazzo, S., Ugrinowitsch, C., & De Souza, E. O. (2022). Progressive Resistance Training Volume: Effects on Muscle Thickness, Mass, and Strength Adaptations in Resistance-Trained Individuals. J Strength Cond Res, 36(3), 600-607. https://doi.org/10.1519/jsc.0000000000003524
Baz-Valle, E., Balsalobre-Fernández, C., Alix-Fages, C., & Santos-Concejero, J. (2022). A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy [journal article]. Journal of Human Kinetics, 81, 199-210. https://doi.org/10.2478/hukin-2022-0017
Buckner, S., Moreno, E., & Baxter, H. (2023). The dose-response relationship between resistance training volume and muscle hypertrophy: There are still doubts. Journal of Trainology, 12, 29-36. https://doi.org/10.17338/trainology.12.2_29
Buckner, S. L., Dankel, S. J., Mattocks, K. T., Jessee, M. B., Mouser, J. G., Counts, B. R., Laurentino, G. C., & Loenneke, J. P. (2017). Differentiating swelling and hypertrophy through indirect assessment of muscle damage in untrained men following repeated bouts of resistance exercise. Eur J Appl Physiol, 117(1), 213-224. https://doi.org/10.1007/s00421-016-3521-9
References
Camargo, J. B. B. d., Barbosa, P. H., Brigatto, F. A., Braz, T. V., & Lopes, C. R. (2023). Muscle Hypertrophy Responses to Changes in Training Volume: A Retrospective Analysis. International Journal of Sports Medicine. https://doi.org/10.1055/a-2053-8426
Heaselgrave, S. R., Blacker, J., Smeuninx, B., McKendry, J., & Breen, L. (2019). Dose-Response Relationship of Weekly Resistance-Training Volume and Frequency on Muscular Adaptations in Trained Men. Int J Sports Physiol Perform, 14(3), 360-368. https://doi.org/10.1123/ijspp.2018-0427
Ostrowski, K. J., Wilson, G. J., Weatherby, R., Murphy, P. W., & Lyttle, A. D. (1997). The Effect of Weight Training Volume on Hormonal Output and Muscular Size and Function. The Journal of Strength & Conditioning Research, 11(3). https://journals.lww.com/nsca-jscr/fulltext/1997/08000/the_effect_of_weight_training_volume_on_hormonal.3.aspx
Schoenfeld, B., & Grgic, J. (2018). Evidence-Based Guidelines for Resistance Training Volume to Maximize Muscle Hypertrophy. Strength & Conditioning Journal, 40(4). https://journals.lww.com/nsca-scj/fulltext/2018/08000/evidence_based_guidelines_for_resistance_training.11.aspx
Schoenfeld, B. J., Contreras, B., Krieger, J., Grgic, J., Delcastillo, K., Belliard, R., & Alto, A. (2019). Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men. Med Sci Sports Exerc, 51(1), 94-103. https://doi.org/10.1249/mss.0000000000001764
Schoenfeld, B. J., Ogborn, D., & Krieger, J. W. (2017a). The dose-response relationship between resistance training volume and muscle hypertrophy: are there really still any doubts? J Sports Sci, 35(20), 1985-1987. https://doi.org/10.1080/02640414.2016.1243800
References
Schoenfeld, B. J., Ogborn, D., & Krieger, J. W. (2017b). Dose-response relationship between weekly resistance training volume and increases in muscle mass: A systematic review and meta-analysis. J Sports Sci, 35(11), 1073-1082. https://doi.org/10.1080/02640414.2016.1210197
Schoenfeld, B. J., Pope, Z. K., Benik, F. M., Hester, G. M., Sellers, J., Nooner, J. L., Schnaiter, J. A., Bond-Williams, K. E., Carter, A. S., Ross, C. L., Just, B. L., Henselmans, M., & Krieger, J. W. (2016). Longer Interset Rest Periods Enhance Muscle Strength and Hypertrophy in Resistance-Trained Men. J Strength Cond Res, 30(7), 1805-1812. https://doi.org/10.1519/jsc.0000000000001272
Additional Information on Muscle Hypertrophy and Training Volume
There is immense complexity between skeletal muscle development, blood flow, protein synthesis, and various forms of exercise training. Emphasizes the role of strength training for increasing muscle fiber mechanical tension and aerobic exercise in enhancing muscle protein synthesis, crucial for building muscle and increasing muscular strength.
For weight loss and reducing body fat, a quick literature search reveals a combination of increasing protein intake, exercise training and a balanced diet. The role of personal trainers in increasing physical activity and designing programs that incorporate muscle recovery and a gradual increase in training variables, like the bench press, to promote muscle building and lean body mass in individuals, including older adults.
What is muscle hypertrophy and how does it work?
Muscle hypertrophy refers to the increase in muscle size and volume. It occurs when muscle fibers undergo damage through exercise, leading to muscle protein synthesis and muscle fiber growth. Over time, repeated muscle damage and repair result in increased muscle size and strength.