Increasing Training Volume: Does It Really Lead to Muscle Growth?

The study, "Training Volume Increases or Maintenance Based on Previous Volume: The Effects on Muscular Adaptations in Trained Males" by Barsuhn et al., published in the Journal of Applied Physiology, investigated the effects of varying training volumes on muscle growth, strength, and endurance in resistance-trained males. Over eight weeks, participants performed either 12 sets (control), 19 sets (30% increase), or 24 sets (60% increase) per week. The findings revealed no significant differences in muscle hypertrophy across groups, with maximal strength gains observed in the 12 sets group and the best endurance improvements in the 19 sets group. These results challenge the notion that higher training volumes always yield superior adaptations, emphasizing the importance of individualized programming and recovery.

Key Points of the Article About Increasing Training Volume: Why More Isn’t Always Better

Increasing training volume beyond a certain threshold does not guarantee better muscle growth in trained lifters.
Maintaining a moderate volume of 12 weekly sets yielded similar muscle growth results compared to higher volumes (up to 24 sets per week).
Strength endurance was best improved with a 30% increase in training volume, while maximal strength gains were observed with consistent training volumes.

The Truth About Increasing Training Volume: How Much is Really Necessary for Muscle Growth?

The relationship between training volume and muscle hypertrophy has been a subject of extensive research and debate within the field of exercise science. Over the past few years, the fitness community has heavily advocated for increasing training volume to maximize muscle growth. Some believe that performing more sets leads to bigger muscles^1-3, but others argue there’s a limit to how much volume is truly beneficial^4-7. It has been suggested that the relationship between training volume and muscle hypertrophy may not be linear, proposing an inverted U-shape model where optimal adaptations occur at moderate volumes (around 5-10 sets per week) rather than excessively high volumes.⁸ Research suggests a threshold beyond which increasing training volume yields diminishing returns or even hampers progress.⁹

The new study titled “Training Volume Increases or Maintenance Based on Previous Volume: The Effects on Muscular Adaptations in Trained Males” by Barsuhn et al., published in the Journal of Applied Physiology, explores this pressing question. His groundbreaking research reveals that maintaining a moderate training volume (~12 sets per week) produced the same muscle growth as significantly higher volumes (~25 sets per week). ¹⁰

Overview of the Study Protocol on Increasing Training Volume

Participants

The study included 55 resistance-trained males, all with at least three years of lifting experience and a back squat strength of at least 1.5 times their body weight. These advanced lifters were ideal for examining whether changes in training volume influenced muscle growth and strength.

Design and Groups

The participants were divided into three groups:

Control Group (12 Sets): Maintained their usual training volume (~12 sets per week).

Moderate Increase (19 sets): Increased weekly volume by 30%, averaging ~19 sets.

High Increase (24 sets): Increased weekly volume by 60%, averaging ~24 sets.

All groups trained twice per week for eight weeks, focusing on the lower body through exercises like back squats, leg presses, and leg extensions. The program alternated between heavy days (6-8 reps per set) and lighter days (12-15 reps per set), with all sets taken close to failure.

Nutritional and Recovery Controls

Participants followed standardized nutrition guidelines, including protein supplementation after workouts. erceived effort and recovery were monitored using established rating scales, ensuring consistent performance across the groups.

Key Results of Increasing Training Volume

The results of the study were eye-opening and challenged conventional wisdom:

Muscle Growth: All groups experienced significant increases in muscle size (thigh muscle thickness and fat-free mass). Surprisingly, there were no meaningful differences in muscle growth between the groups. Both the moderate (19 sets) and high-volume (24 sets) groups achieved similar gains compared to the control group (12 sets). These results suggest that increasing weekly training volume from 12 to 19 or 24 sets does not lead to greater muscle hypertrophy.

Strength Gains

Strength improvements were most pronounced in the 12 sets group, which recorded an average increase of 70 pounds in back squat strength. The 19 sets group gained 46 pounds on average, while the 24 sets group gained 42 pounds, the smallest increase among the three groups. These findings indicate that excessive volume may hinder strength gains due to fatigue or insufficient recovery time.

Endurance Performance

Endurance performance, measured by repetitions to failure at 70% of 1RM, showed the most improvement in the 19 sets group, with an average increase of 5.45 repetitions. In contrast, the 12 sets group saw a marginal improvement of 0.13 repetitions, while the 24 sets group experienced a slight decrease of 0.41 repetitions. This suggests that moderate increases in training volume may enhance endurance, but excessive volume could lead to diminished returns due to accumulated fatigue.

Is Increasing Training Volume Always Beneficial?

While it’s tempting to think that more sets equal bigger muscles, research shows otherwise. The researchers found no significant differences in hypertrophy across the 12 sets, 19 sets, and 24 sets groups, supporting the idea that additional sets don’t lead to further gainsonce a certain threshold is met. This aligns with findings from Schoenfeld et al., who reported that exceeding moderate training volumes adds little benefit to muscle size. Think of muscle growth like watering a plant; after a point, more water doesn’t make the plant grow faster—it can even drown it.

Strength and Overtraining Risks

Surprisingly, the 12 sets group achieved the greatest strength improvements. This suggests that overtraining might interfere with strength development, as recovery plays a crucial role in adapting to resistance training. Previous studies have also shown that maintaining moderate training volumes can optimize strength without causing fatigue.⁸

Practical Applications For Increasing Training Volume

Prioritize Moderate Volumes: For most lifters, maintaining ~12 weekly sets for major muscle groups is sufficient for muscle growth. Excessive volumes might not add value and could hinder recovery.
Strategic Increases for Endurance: If improving endurance is your goal, consider a small increase in weekly sets (e.g., 19 sets). This approach can enhance endurance without causing fatigue.
Emphasize Recovery: The 12 sets group’s superior strength gains highlight the importance of recovery. Ensure adequate rest between sessions, and consider using recovery tools like foam rolling or yoga to enhance performance.
Monitor Progress and Adjust Accordingly: Use a journal or app to track your performance. f progress stalls, assess your training volume and recovery strategies before making drastic changes.
Quality Over Quantity: Focus on perfecting form, controlling tempos, and pushing close to failure rather than simply adding more sets. Quality reps produce better results than mindlessly increasing volume (Franchi et al., 2018).

References

1 Schoenfeld, B. J. et al. Resistance Training Volume Enhances Muscle Hypertrophy but Not Strength in Trained Men. Med Sci Sports Exerc 51, 94-103 (2019). https://doi.org/10.1249/mss.0000000000001764

2 Baz-Valle, E., Balsalobre-Fernández, C., Alix-Fages, C. & Santos-Concejero, J. A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy. Journal of Human Kinetics 81, 199-210 (2022). https://doi.org/10.2478/hukin-2022-0017

3 Hamarsland, H. et al. Equal-Volume Strength Training With Different Training Frequencies Induces Similar Muscle Hypertrophy and Strength Improvement in Trained Participants. Frontiers in Physiology 12 (2022). https://doi.org/10.3389/fphys.2021.789403

4 Souza, D., Barbalho, M. & Gentil, P. The Impact of Resistance Training Volume on Muscle Size and Lean Body Mass: To Infinity and Beyond? Human Movement 21, 18-29 (2020). https://doi.org/10.5114/hm.2020.94199

5 L. Buckner, S., N. Moreno, E. & T. Baxter, H. The Dose-Response Relationship Between Resistance Training Volume and Muscle Hypertrophy: There Are Still Doubts. Journal of Trainology 12, 29-36 (2023). https://doi.org/10.17338/trainology.12.2_29

6 Mangine, G. T. et al. The Effect of Training Volume and Intensity on Improvements in Muscular Strength and Size in Resistance-Trained Men. Physiological Reports 3, e12472 (2015). https://doi.org/10.14814/phy2.12472

7 Lasevicius, T. et al. Muscle Failure Promotes Greater Muscle Hypertrophy in Low-Load but Not in High-Load Resistance Training. The Journal of Strength and Conditioning Research 36, 346-351 (2019). https://doi.org/10.1519/jsc.0000000000003454

8 Radaelli, R. et al. Low- and high-volume strength training induces similar neuromuscular improvements in muscle quality in elderly women. Exp Gerontol 48, 710-716 (2013). https://doi.org/10.1016/j.exger.2013.04.003

9 Ghoual, A. The Effect of Repetition Ranges on Maximal Strength and Hypertrophy. International Journal of Physical Education Fitness and Sports, 149-157 (2019). https://doi.org/10.26524/ijpefs19415

10 Barsuhn, A. et al. Training Volume Increases Or Maintenance Based On Previous Volume: The Effects On Muscular Adaptations In Trained Males. Journal of Applied Physiology 0, null https://doi.org/10.1152/japplphysiol.00476.2024