Smashing the Volume Button Might not Improve Hypertrophy

More volume is often treated like a path to more muscle. But what happens when you crank weekly sets way up, all at once, in trained lifters? This new preprint suggests that smashing the volume button does not seem to impair hypertrophy, but it also does not appear to offer a clear advantage over a more moderate increase.

Overview

• What did they test? The researchers tested whether a large increase in weekly quadriceps training volume (+120% above habitual volume) would impair hypertrophy or alter anabolic and catabolic molecular signaling compared with a modest increase (+20%) in resistance-trained men and women. Each participant trained both legs, with one leg assigned to the high-volume condition and the other to the modest-volume condition for 8 weeks.
• What did they find? Both volume conditions increased muscle cross-sectional area over time, but the larger increase in volume did not produce different hypertrophy from the modest increase. Muscle fiber cross-sectional area, satellite cell content, and myonuclear content also did not differ between conditions, and most molecular markers were similar between conditions.
• What does it mean for you? In trained lifters, a very large jump in weekly set volume did not seem to be harmful over 8 weeks, but it also did not clearly outperform a more modest increase. This suggests that there may be more room for short-term tolerance to high volumes than some people think, but that moderate increases in volume are probably a better way to go if you’re looking to use volume as a progressive overload tool.

What’s the Problem?

Training volume is one of the main drivers of hypertrophy, and the broader literature generally supports a positive dose-response relationship between weekly sets and muscle growth. However, that relationship does not appear to be linear forever. Recent meta-regression work suggests that hypertrophy tends to increase as weekly volume rises, but with diminishing returns as volume gets higher 1. That makes volume important, but it also raises a practical question: at what point does adding more work stop being meaningfully productive?

The literature is more mixed than many people assume. Some studies suggest that higher volumes can produce greater hypertrophy in resistance-trained men, such as work showing advantages for 32 weekly sets compared with 16 weekly sets for some muscle groups 2 and prior data showing greater hypertrophy with higher resistance training volume in trained men completing 15 sets per week compared to 9 sets 3. At the same time, other studies indicate that the response depends heavily on context. Aube et al. (2022) reported similar hypertrophy despite different progressive volume prescriptions 4, and Scarpelli et al. (2022) showed that hypertrophy in trained individuals was affected by previous training volume, with individualized progression outperforming a standardized prescription 5. Together, these studies suggest that in trained lifters, the issue is not simply whether more volume works, but whether a given increase is appropriate relative to what the athlete was already doing.

There is also a plausible mechanistic reason to think that very large increases in workload might eventually become counterproductive. Experimental evidence from animal models indicates that when recovery between resistance exercise bouts is shortened too much, anabolic signaling can remain elevated without a matching increase in protein synthesis, while proteolytic and inflammatory signaling rise enough to blunt hypertrophy 6 7. In a 2017 mouse study, repeated bouts with only 8 hours of recovery activated mTOR signaling but failed to increase protein synthesis, unlike 24- and 72-hour recovery conditions 6. In a 2019 rat study, training sessions performed every 8 hours did not produce hypertrophy and were accompanied by activation of protein degradation systems and inflammatory responses 7. This could mean, from a human perspective, that if you can’t recover from the training you may not adapt. Of course, these rodent data should be interpreted cautiously, but they still provide a useful mechanistic signal that insufficient recovery can uncouple anabolic signaling from muscle growth.

Purpose

The purpose of the study was to determine whether a large increase in weekly resistance training volume (+120%) attenuates hypertrophic adaptations and alters molecular markers related to anabolic and proteolytic regulation compared with a modest increase (+20%) in resistance-trained individuals.

Hypothesis