Selected publication milestones, not an exhaustive history or discovery priority claim.
1991 — 1991 a small older-adult controlled study reports measured-VO2max benefit from training below measured lactate threshold. Original PMID2072834.
1992 — 1992 a larger healthy-older-adult attention-controlled trial establishes conventional moderate-cycling fitness gains without verifying individual below-VT1 exposure. Original PMID1727835.
1999 — 1999 HERITAGE documents substantial variation and familial resemblance in training-associated maximal-oxygen-uptake gain. Original PMID10484570.
2001 — 2001 HERITAGE retrospectively relates achieved intensity to measured threshold adaptation; maximal-VO2 change is not explained by initial position relative to VT. Original PMID11719894.
2007 — 2007 energy-matched low and moderate exercise gives similar maximal-fitness changes but different threshold responses and test-effort caveats. Original PMID17213964.
2008 — 2008 a volume-controlled randomized intensity trial finds greater VO2max improvements at higher intensities under relative-reserve prescriptions. Original PMID18580415.
2013 — 2013 polarized cycling improves selected performance measures without mitochondrial-enzyme change, separating functional adaptation from a uniform marker account. Original PMID23264537.
2015 — 2015 individualized VT1/VT2 exercise prescription improves fitness more than relative heart-rate-reserve prescription, while mixed-zone exposure requires explicit separation. Original PMID26146564.
2018 — 2018 a large clinical treadmill cohort strengthens fitness prognosis but does not identify a mortality mediator. Original PMID30646252.
2020 — 2020 Generation100 randomizes long-term exercise against activity guidelines and finds a combined mortality null with modest fitness separation and crossover. Original PMID33028588.
2024 — 2024 a randomized individualized-domain trial finds no significant six-week moderate-domain fitness advantage versus control, mapping a boundary to universal low-domain benefit. Original PMID38376995.
2025 — 2025 model-specific Garmin validation illustrates relatively favourable fitness prediction alongside poor oxygen-saturation concordance. Original PMID39797066.
2025 — 2025 fitness-longevity Mendelian randomization reports no genetically predicted VO2max association, challenging isolated causal interpretation of prognosis. Original PMID38864459.
2025 — 2025 isocaloric randomized training in cancer survivors yields similar fitness gains while planned polarized exposure is not achieved. Original PMID40198065.
2026 — 2026 adding low-domain volume to intervals produces no detected additional six-week performance benefit in a small trained cohort. Original PMID42560532.
2026 — 2026 Pixel Watch3 validation finds low mean VO2max bias but wide individual agreement, limiting use for small clinical changes. Original PMID42743109.
Replication of exclusive below-first-threshold training against no added training with modern measurement and transparent older-study methods
A reproducible definition linking popular five-zone labels with the three-domain first-threshold boundary
Dose, progression, adherence and disease boundaries specified before outcomes rather than by responding subgroups
An isolated oxidative mediator instead of parallel biomarker change
Mortality mediation distinct from prognosis, disease-specific genetics and broad exercise benefit
Individual wearable agreement and detectable change across hardware, algorithms, exercise modes and clinical cohorts
Randomize baseline-defined sedentary and stable clinical adult strata to exclusive measured-below-LT1 training, volume-matched above-LT1 training or attention control for twelve weeks. Determine LT1/VT1 with preregistered algorithms, repeat threshold testing as fitness changes, record achieved exposure and adherence, and blind direct-gas-exchange maximal-test adjudication. Add predefined skeletal-muscle oxidative measurements as candidate mediators without asserting them necessary solely because they correlate.