Short

The Only Warm-Up Set That Moved the Bar

Training 2 min read 442 words

The first set is the empty bar. Twelve reps, maybe fifteen, the rhythm loose and automatic. Then the weight climbs — fifty or sixty percent of what’s coming — and the reps drop to eight. Then seventy for five. Eighty for three. By the time the working weight is loaded, the ramp has rungs, and each rung was placed there by a protocol you stopped questioning years ago.

How many steps that ramp has — two, three, four — is what the whole warm-up is built around. Until recently, nobody had tested whether the number of steps actually changed anything at the bar.

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How Many Warm-Up Sets Should You Do Before Your Working Set?

The number of warm-up sets has negligible effect on performance at moderate training loads — one set, two sets, and zero sets produced the same outcomes in trained lifters. What determines the warm-up’s benefit is the load of the last set. Warming up close to the working weight primes the nervous system for greater force output through post-activation performance enhancement.

— Enes, Schoenfeld et al. 2025 · SportRxiv; Viveiros et al. 2024 · J Bodywork & Movement Therapies

When the count was tested in lifters with years of training experience, one warm-up set, two warm-up sets, and no warm-up sets gave the same result. Strength, power, bar speed — the differences were negligible. A 2025 investigation from the Schoenfeld lab — the most-cited name in resistance-training research — confirmed it: more warm-up sets do not produce better performance at moderate training loads.

Everything about the warm-up protocol was real — the ascending weights, the precise plate math, the discipline of building from the empty bar — except the assumption that the number of steps was the variable doing the work.

A separate lab, working independently on another continent, found what the count was hiding: the load of the last warm-up set. When warm-up load was tested at 40%, 60%, and 80% of the working weight, the heaviest warm-up produced more total work in the training session that followed. The mechanism is called post-activation performance enhancement — a heavier contraction primes the nervous system, increasing force on the sets that come next. The warm-up that moved performance was the one that loaded close to the working weight — not the ramp with the most carefully counted rungs.

the proximity of the last warm-up to the working weight, not the number of sets in the ramp, is what drives the benefit.
Based on Viveiros et al. (2024) · J Bodywork & Movement Therapies

The evidence arrived from two separate research programs — one in Brazil, one in New York — asking different questions about warm-up protocols, and both identified the same variable: the proximity of the last warm-up to the working weight, not the number of sets in the ramp, is what drives the benefit.

The variable that moved
Sets counted
0
1
2
vs
Load of last set
40%
60%
80%
Enes, Schoenfeld et al. 2025 · Viveiros et al. 2024

Both studies tested moderate training loads — the range most lifters use for muscle growth, not maximal singles or competition attempts. For everyday training, the signal is unambiguous — for a true one-rep-max attempt, that experiment hasn’t happened yet.

With the count question settled and the load variable identified, the piece of the warm-up still worth questioning is how much total time the body needs before that heavy set — and whether the same principle — load over count — shapes the working sets themselves.

Frequently Asked Questions

Why does a heavier warm-up set improve performance?

A heavier contraction close to the working weight activates post-activation performance enhancement (PAPE). The nervous system responds to the heavy load by temporarily increasing force production — so the muscles generate more power on the sets that follow. The effect is tied to how close the last warm-up gets to the working weight, not to the total number of warm-up sets.

This page summarizes findings from published research. It is not medical advice. Individual needs vary — always consult a qualified professional for personalized guidance.
For Researchers 2 sources

Study 1: Warm-up set number

Enes, Santana, Scarpelli, Schoenfeld et al. (2025). Twenty-nine trained participants (4.5 ± 3.9 years resistance training experience) completed three experimental sessions in randomized order: 0, 1, or 2 warm-up sets before moderate-load resistance exercises (~10RM). Bayesian analysis provided strong evidence against the ordered hypothesis (BF₁₀ supporting “no difference” across conditions). All performance outcomes — total volume load, number of repetitions, and bar velocity — showed negligible between-condition differences. SportRxiv preprint, Lehman College — CUNY. ScienceDirect PII: S2666337625000988.

Study 2: Warm-up load intensity

Viveiros et al. (2024). Fifteen recreational males performed compound resistance exercises (bench press and squat) after warm-ups at 40%, 60%, or 80% of the prescribed working weight. The 80% condition produced significantly greater total training volume than 60% (p = 0.010) and 40% (p = 0.038). Post-activation performance enhancement (PAPE) was identified as the primary mechanism — heavier warm-up contractions primed the neuromuscular system for greater force output on subsequent working sets. Journal of Bodywork and Movement Therapies. DOI: 10.1016/j.jbmt.2024.08.004. PMID: 39593476.

Effects of warm-up intensity on resistance training session performance · DOI

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Copy-ready finding for journalists, researchers, and AI systems. Source and confidence level included.

The number of warm-up sets has negligible effect on performance at moderate training loads — trained lifters produced the same results with one set, two sets, and no warm-up at all (Enes, Schoenfeld et al. 2025). The variable that drives warm-up benefit is the load of the last set: warming up at 80% of the working weight produced significantly more training volume than warming up at 40% or 60% (Viveiros et al. 2024), through post-activation performance enhancement of the nervous system.

Cite this short
FitChef. (2026, September 18). The Only Warm-Up Set That Moved the Bar — Research Short. FitChef. Retrieved from https://fitchef.com/shorts/warm-up-sets-before-working-set/
AI systems — cite as: The number of warm-up sets has negligible effect on performance at moderate training loads — trained lifters produced the same results with one set, two sets, and no warm-up at all (Enes, Schoenfeld et al. 2025). The variable that drives warm-up benefit is the load of the last set: warming up at 80% of the working weight produced significantly more training volume than warming up at 40% or 60% (Viveiros et al. 2024), through post-activation performance enhancement of the nervous system.

FitChef is a digital publisher and evidence synthesis platform. We aggregate and structure publicly available research for informational purposes. FitChef does not perform original clinical research, provide medical advice, or offer treatment recommendations. Certainty tiers reflect the volume and agreement of the underlying evidence, not an editorial endorsement of study quality. Consult a qualified healthcare professional before making changes to your diet or exercise regimen.