Training · Moderate evidence
Minimum Effective Dose and Time-Efficient Training
A few well-executed sets, two to three times a week, already yield meaningful gains; supersets and combined sets shorten the session without losing volume.
Systematic review, narrative review, and meta-analysis · 3 sources · 2 min
What the studies show
- A single set of 6 to 12 repetitions at high effort, 2 to 3 times per week, increased 1RM in trained men.
- Around 4 weekly sets per muscle, at 6 to 15 reps, close to failure, serves as a practical floor for hypertrophy.
- Supersets reduce session duration with similar adaptations, at the expense of higher internal fatigue.
How Letz applies it
Sessions of 15 to 30 minutes are never dismissed: the generator trims exercises and sets while preserving foundational movement patterns and the volume floor.
Numbers derived from this rule
| Parameter | Range | Weight | Rule |
|---|---|---|---|
| Weekly sets per muscle group | 10–20 sets/week2 variants by context | 90% | Ten or more weekly sets per muscle produce greater hypertrophy; below four, the stimulus is insufficient; above twenty, returns diminish.Weekly Volume: Sets per Muscle Group · Minimum Effective Dose and Time-Efficient Training |
| Rest for compound exercises | 90–180 seconds | 60% | Compound exercises perform better with two minutes or more of rest; 90 seconds is the floor when time is limited.Rest Between Sets · Minimum Effective Dose and Time-Efficient Training |
Who it applies to
Time-constrained adults, including trained individuals.
Limits
The minimum dose is suboptimal for those seeking maximal results; supersets increase perceived effort and may require more recovery.
Sources
- Androulakis-Korakakis et al., Sports Medicine, 2020 DOI 10.1007/s40279-019-01236-0
- Iversen et al., Sports Medicine, 2021 DOI 10.1007/s40279-021-01490-1
- Zhang et al., Sports Medicine, 2025 DOI 10.1007/s40279-025-02176-8
More in Training
- Resistance Training, Strength, and HypertrophyVarious training prescriptions improve strength and hypertrophy; heavier loads favor strength, and multiple sets favor hypertrophy.
- Weekly Volume: Sets per Muscle GroupMore weekly sets per muscle produce greater hypertrophy, with diminishing returns; for strength, moderate volumes already capture most of the gains.
- Frequency: training each muscle at least twice per weekTraining a muscle group twice a week is superior to once for hypertrophy; for strength, higher frequency helps primarily because it distributes volume more effectively.
- Load and rep rangeLight and heavy loads produce similar hypertrophy when sets are taken close to failure; heavy loads are superior for maximizing strength gains.