§ Claim under review · Study
"Most lifters assume building muscle requires several working sets for every exercise. Researchers tested a much smaller dose: trained men and women performed one working set across nine exercises, twice per week, for eight weeks. They still gained muscle and improved strength. This doesn't prove one set is optimal but it shows the minimum effective dose may be far lower than most lifters assume. More volume can produce more growth. But very little can still work. Source: Hermann et al., Medicine & Science in Sports & Exercise (2025), PMID: 40249908."
Verdict
Mostly accurate
Confidence
HighSummary
This post cites a real study. Hermann and colleagues, published in Medicine and Science in Sports and Exercise in 2025, had 42 young resistance trained men and women perform one set of nine exercises twice per week for eight weeks, and both study groups showed gains in most measures of muscle size, strength, power and endurance. The post describes the protocol and the result correctly, and it is appropriately cautious in saying this does not prove one set is optimal. The key detail it leaves out is that every set was taken either to muscular failure or to within two repetitions of failure, so this was one very hard set, not one casual set. It also omits that the study had no control group and no higher volume comparison group, because its actual purpose was to compare training to failure against stopping short, not to compare one set against several. The participants were already trained and were coming from higher volume programs, and the trial lasted only eight weeks, so it cannot tell you what happens over the long term. Overall the claim is mostly accurate with some missing context that matters for how you would apply it.
The readings
key figures from the evidenceduration of the single-set training protocol
Bayes factor for FAIL group's mid-quadriceps thickness advantage
Why this verdict
Evidence
The cited study is real, the PMID and journal details match, and the description of the protocol is accurate. Forty-two young, resistance-trained men and women were randomly assigned to one of two parallel groups: a group that trained to failure on all exercises (FAIL) or a submaximal effort group (2-RIR) that trained with two repetitions in reserve for the same exercises. Participants performed a single set of nine exercises targeting all major muscle groups per session, twice weekly for 8 wk.
Researchers assessed pre to post changes in muscle thickness for the biceps brachii, triceps brachii, and quadriceps femoris, along with measures of muscular strength, power, endurance, and ability to estimate RIR in the bench press and squat. Results indicated that both FAIL and 2-RIR elicited appreciable gains in most of the assessed outcomes.
On between group differences, several measures of hypertrophy tended to favor FAIL, although absolute differences between conditions were generally modest, increases in countermovement jump height favored FAIL but with no clear statistical support for either the null or alternative hypothesis, and increases in strength and local muscular endurance were similar between conditions.
The authors' own conclusion aligns with the post's framing: single-set routines can be a time-efficient strategy for promoting muscular adaptations in resistance-trained individuals, even when transitioning from higher-volume programs, and training to failure in single-set routines may modestly enhance some measures of muscle hypertrophy and power, but not strength or local muscle endurance.
The preprint is keyworded with "time-efficient training, minimum effective dose, set end point, proximity to failure, muscle hypertophy, strength."
Findings
✓ What's accurate 5
- The citation is genuine and correctly attributed. Hermann et al., Med Sci Sports Exerc 2025, PMID 40249908 exists and matches the described study.
- The protocol description is accurate: one working set, nine exercises, twice weekly, eight weeks, in trained men and women.
- The core finding is accurately reported. Both groups showed appreciable gains in most assessed outcomes , which included size and strength measures.
- The hedging is appropriate and matches the authors. The post says it does not prove one set is optimal, and the authors themselves frame the finding as time efficiency rather than optimality.
- "More volume can produce more growth" is consistent with the broader literature the post does not cite, including meta-analytic findings that outcomes for weekly sets categorised as lower or higher within each study showed a significant effect of volume on changes in muscle size .
≈ What's misleading 5
- Omitted qualifier, effort level. The post says "one working set" without noting that every set was taken to failure or to within two reps of failure. A single low effort set is not what was tested. This matters because a reader could take away that any single set works.
- Omitted qualifier, study design. The post implies researchers set out to test a minimum effective dose. The trial had no control group and no multi-set comparator, so it cannot quantify how single-set training compares to higher volume. It compared two effort levels within a single-set framework.
- Omitted qualifier, population and starting point. Participants were young, already resistance trained, and in many cases transitioning from higher-volume programs . Short term gains in people reducing volume from a prior higher-volume baseline are not the same as long term growth from a standing start.
- Slight framing stretch. "One working set across nine exercises" reads as very little, but twice weekly sessions mean roughly two hard sets per muscle group per week over eight weeks, which is a defined and non-trivial stimulus.
- Duration. Eight weeks is short. The post's "minimum effective dose" language implies a durable conclusion that an eight week trial cannot establish.
? What's uncertain 4
- Exact effect sizes for within group hypertrophy and strength gains. The abstract and the preprint snippets available report direction and between group comparisons but I could not retrieve the full results tables with raw millimetre and kilogram changes. "Appreciable gains" is the authors' wording, not a quantified figure.
- Dropout and completion numbers. Forty-two were randomized; the number who completed each arm was not visible in the retrieved material.
- Whether every muscle site showed growth. The abstract says gains occurred in "most" assessed outcomes, which implies some did not, but which ones is not specified in the retrieved text.
- Diet, protein intake and outside training control during the intervention were not visible in the retrieved abstract.
Sources
1 of 6 linked to recordsHermann T, Mohan AE, Enes A, Sapuppo M, Piñero A, Zamanzadeh A, Roberts M, Coleman M, Androulakis-Korakakis P, Wolf M, Refalo M, Swinton PA, Schoenfeld BJ. "Without Fail: Muscular Adaptations in Single-Set Resistance Training Performed to Failure or with Repetitions-in-Reserve." Med Sci Sports Exerc. 2025 Sep;57(9):2021-2031. DOI 10.1249/MSS.0000000000003728. Primary, peer reviewed journal. https://journals.lww.com/acsm-msse/abstract/2025/09000/without_fail__muscular_adaptations_in_single_set.19.aspx
Preprint version of the same study, SportRxiv. Primary, non peer reviewed preprint with results tables. https://sportrxiv.org/index.php/server/preprint/view/484
Ovid publisher abstract and plain language summary of the same article. Primary/publisher. https://www.ovid.com/jnls/acsm-msse/abstract/10.1249/mss.0000000000003728
Robert Gordon University institutional repository record (co-author Swinton). Primary/institutional. https://rgu-repository.worktribe.com/output/2788957/
Biolayne research review of the study. Secondary commentary. https://biolayne.com/reps/issue-37/
Yahoo Health consumer coverage. Secondary journalism. https://health.yahoo.com/wellness/fitness/exercise/articles/study-says-one-set-rule-143607354.html