Same Gains from Double the Volume: Why More Sets Don't Always Mean More Muscle
Inside the study that compared conservative and aggressive volume ramp-ups in trained men and women.
Does more volume mean more muscle? Not necessarily. A new study finally explored what happens when you nearly double your training volume overnight. Do you grow muscle faster, or does fatigue become too much of a limiting factor?
Researchers recruited 25 trained men and women, had each person train both legs simultaneously under very different volume conditions for 8 weeks, and then measured everything from gross muscle size to the molecular signals controlling muscle growth and breakdown. They found that a whopping 120% increase in weekly training volume produced the same muscle growth as a modest 20% increase. The muscle's internal machinery, the anabolic and catabolic signalling pathways, responded almost identically between conditions. For lifters who worry about "too much, too soon," or for coaches debating how aggressively to ramp up training loads, this study offers a surprisingly reassuring answer.
Aim
The central question of the study was whether a large, abrupt jump in weekly training volume (+120% above habitual volume) would impair or attenuate muscle hypertrophy and shift the body toward a catabolic (muscle-breakdown) state compared to a modest volume increase (+20%).
Researchers from the Federal University of São Carlos (Brazil) and Auburn University (USA) hypothesised that the larger volume spike would overload the muscle's adaptive capacity, disrupt the balance between muscle-building and muscle-breakdown signals, and ultimately produce less growth.
Methods
25 resistance-trained men and women aged 18 to 35 years, with 1 to 5 years of consistent lower-body training experience, completed a randomised, single-blind, 8-week intervention. The study used a within-subject unilateral design, meaning each participant trained both legs simultaneously but under different volume conditions, one leg assigned to the low-volume condition (VOL20, +20% above habitual sets) and the other to the high-volume condition (VOL120, +120% above habitual sets).
Both legs were trained twice per week using the 45-degree leg press and leg extension, with all sets taken to concentric failure in the 9 to 12 rep range and 2-minute rest periods. Participants had an average pre-study weekly set volume of about 15 sets per week for the quadriceps, meaning VOL20 added roughly 3 sets per week while VOL120 added roughly 18 sets per week.
Over the 8 weeks, VOL120 accumulated an average of approximately 32.8 sets per week compared to 18.0 sets per week for VOL20. Total volume load across the intervention was approximately 237,125 kg for VOL120 versus approximately 138,416 kg for VOL20.
Muscle size was assessed using ultrasound to measure vastus lateralis muscle cross-sectional area (mCSA) before and after training. Muscle biopsies from the vastus lateralis were taken at three time points to measure muscle fibre cross-sectional area (fCSA), satellite cells, myonuclei, and a broad panel of anabolic and catabolic molecular markers. Participants were also given 30g of whey protein after each session to standardise post-exercise nutrition.
Results
Both protocols produced significant increases in vastus lateralis mCSA over the 8 weeks, with no difference in the magnitude of change between conditions. Despite VOL120 having a marginally higher absolute mCSA at both time points, the between-protocol difference in the pre-to-post change was only about 2.7%, which is very close to the ultrasound measurement’s natural margin of error (2.3%). This means the difference was too small to be meaningfully attributed to the training condition.
Neither protocol produced a detectable change in muscle fibre cross-sectional area, satellite cell numbers, or myonuclear content, which the authors note is consistent with previous research in trained populations. Fascicle length and pennation angle also remained unchanged in both legs.
At the molecular level, the vast majority of anabolic and catabolic signalling markers were comparable between conditions, both acutely (24 hours after a session) and chronically (after the full 8 weeks). A few notable findings include:
Calpain-1 and calpain-2 protein content increased in both conditions over time, but enzymatic calpain activity did not change, suggesting increased protein presence does not automatically mean increased breakdown activity
FOXO3, a marker associated with protein breakdown and autophagy, was reduced after the intervention in both conditions, suggesting training did not push either group into a sustained catabolic state
45S pre-rRNA expression (a marker of ribosome biogenesis, or the machinery that builds muscle proteins) increased in both conditions, and was slightly higher in VOL120, though this did not translate to greater hypertrophy
Myostatin gene expression (a brake on muscle growth) was reduced after training in both conditions, again independent of volume
Proteasome activity acutely increased in both conditions after exercise, but was unexpectedly slightly higher in VOL20 than VOL120, suggesting the high-volume group did not experience greater protein breakdown post-exercise
Takeaways
Doubling your training volume overnight does not appear to sabotage muscle growth. In trained people, the muscle adapts and grows similarly whether volume is pushed aggressively or increased conservatively, at least over 8 weeks.
More volume does not mean more anabolic signalling. The high-volume group did not produce stronger growth signals, which challenges the assumption that piling on sets always means a bigger hormonal or cellular response.
There is no sign of a catabolic crisis with high volume. The feared scenario where excessive training flips the body into a breakdown-dominant state was not observed here, either in terms of muscle size or molecular markers.
"Optimal volume" may matter less than commonly assumed for trained people. These findings add to a growing body of evidence suggesting that trained muscle is more adaptable and resilient to volume fluctuations than once thought
Context matters. Participants were recreationally trained (not elite athletes), were followed for only 8 weeks, and had protein and nutrition standardised throughout. Results may look different in highly trained lifters, longer-term programs, or without nutritional support.
If you need to ramp up volume quickly (e.g., returning from a break, starting a new training block), this study suggests you do not need to be overly cautious about taking a big jump in sets, at least in the short term.
Reference
Large increases in resistance training volume do not impair skeletal muscle hypertrophy or anabolic–catabolic molecular signalling in trained individuals. Júlio B. B. Camargo, Diego Bittencourt, J. Max Michel, Deivid G. Silva, João G. A. Bergamasco, Dakota R. Tiede, Dustyn Lewis, Enya T. A. Nacafucasaco, Otávio Ferrari, Ana C. C. Melo, Matheus Iasulaitis, Marcelo Rebelato, Michael D. Roberts, Cleiton A. Libardi
bioRxiv 2026.02.23.707462; doi: https://doi.org/10.64898/2026.02.23.707462
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