A narrative review arguing for the polarized model: nearly all training "light" (RPE ≤13) or "very hard" (RPE ≥17), very little at "hard"/race pace (14-16), with long slow distance kept below VT1 / 2 mM lactate
The authors report effect sizes consistently favouring polarized over threshold training
Key Findings (abstract)
Traditional threshold, high-volume and high-intensity models are described as giving limited improvement in race pace in (highly) trained individuals while often leading to overreaching or overtraining.
A polarized program is defined as undulating, non-linear periodization with nearly all training time at a "light" (RPE ≤13, 6-20 scale) and "very hard" (RPE ≥17) effort and very limited time at "hard" (14-16) or race pace.
High-intensity workouts are separated by one or more long slow distance sessions kept below VT1 and/or below 2 mM blood lactate.
The authors state that effect sizes for improving aerobic endurance performance are consistently superior for the polarized model than for the threshold model, based on the five studies they summarise.
Their practical summary: go easy on long slow distance, avoid "race pace", work hard in the interval sessions.
Practical Application
Narrative review (Hydren & Cohen 2015): define polarized training by effort — nearly all time at RPE ≤13 (below VT1 / 2 mM) or ≥17, very little at 14-16 — and the authors report polarized beating threshold training on effect size across the five studies they summarise. Use it as a clear description of what "polarized" means in practice, not as the evidence that it is superior: the comparative evidence is the underlying trials, e.g. REF-303.
Not from this paper; the base's own practice: the RPE bands are a practical way to police the easy days when no lactate or gas-exchange test exists.
Limitations
Narrative review: five studies summarised, no systematic search or pooling reported in the abstract; "proven" and "consistently superior" are the authors' framing.
The example training programs are the authors' construction, not tested prescriptions.
Full text not read; everything above is from the abstract.
How this entry was checked and changed
Why this level
narrative review without systematic method; it summarises five studies rather than pooling them
Content correction 2026-09-27
Entry was an empty stub (header and DOI only). The DOI was checked to resolve to this exact work (Crossref: Hydren & Cohen, JSCR 2015, same title), and the entry was filled from the abstract; PMID from the record the DOI returns. Level set to C+ (narrative review).