Start here
- • Start with consistency: weekly volume stability beats occasional monster long runs.
- • Use intensity sparingly: one quality session + one long session per week is enough for most.
- • Progress one variable at a time: volume first, then density, then intensity.
Topic guides
Practical starting points to test conservatively.
HYROX performance research: what aspiring athletes can use
Evidence-informed protocol: HYROX performance research: what aspiring athletes can use. Practical steps, who it helps, and what to watch out for.
Long-course triathlon research: pacing, fueling and readiness
Evidence-informed protocol: Long-course triathlon research: pacing, fueling and readiness. Practical steps, who it helps, and what to watch out for.
Related outcomes
Time to exhaustion
A lab outcome that can still guide training: it often tracks fatigue resistance.
Time-trial performance
Practical performance outcome used in many studies: closer to racing than lab-only metrics.
Performance in heat
Heat punishes ego pacing; you need acclimation and cooling strategy to execute.
Recovery speed
Faster recovery means you can train consistently — the real performance moat.
Study library (reference)
Individual studies for deeper reading.
Effects of high-intensity interval and moderate-intensity continuous training on the anaerobic threshold of highly trained athletes in endurance sports: a systematic review with meta-analysis.
Human research · 2024 · The Journal of sports medicine and physical fitness · PubMed 38842374
A training goal-oriented categorization model of high-intensity interval training.
Population not classified in the source record · 2024 · Frontiers in physiology · PubMed 38957216
Physiological adaptations and performance enhancement with combined blood flow restricted and interval training: A systematic review with meta-analysis.
Human research · 2025 · Journal of sport and health science · PubMed 39986351
Meta-analysis of high-intensity interval training and alternative modalities for enhancing aerobic and anaerobic endurance in young athletes.
Human research · 2025 · Physiological reports · PubMed 41047659
Effects of Small-Sided Games vs. Conventional Endurance Training on Endurance Performance in Male Youth Soccer Players: A Meta-Analytical Comparison.
Human research · 2019 · Sports medicine (Auckland, N.Z.) · PubMed 30868441
The Effects of High-Intensity Interval Training on Basketball Players: A Systematic Review and Meta-Analysis.
Human research · 2025 · Journal of sports science & medicine · PubMed 40046212
Effects of Precooling on Endurance Exercise Performance in the Heat: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
Human research · 2024 · Nutrients · PubMed 39683610
How much does sleep deprivation impair endurance performance? A systematic review and meta-analysis.
Human research · 2023 · European journal of sport science · PubMed 36472094
Effects of high-intensity interval training in men soccer player's physical fitness: A systematic review with meta-analysis of randomized-controlled and non-controlled trials.
Human research · 2021 · Journal of sports sciences · PubMed 33423603
Effects of different exercise training modes on muscle strength and physical performance in older people with sarcopenia: a systematic review and meta-analysis.
Human research · 2021 · BMC geriatrics · PubMed 34911483
Sprint interval training effects on aerobic capacity: a systematic review and meta-analysis.
Human research · 2014 · Sports medicine (Auckland, N.Z.) · PubMed 24129784
Effects of sprint interval training on VO2max and aerobic exercise performance: A systematic review and meta-analysis.
Human research · 2013 · Scandinavian journal of medicine & science in sports · PubMed 23889316
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Performance Science Lab
Research summaries for endurance athletes, with study context, practical protocols, and clear limitations.
Open guideHYROX performance research: what aspiring athletes can use
Evidence-informed protocol: HYROX performance research: what aspiring athletes can use. Practical steps, who it helps, and what to watch out for.
Open guideLong-course triathlon research: pacing, fueling and readiness
Evidence-informed protocol: Long-course triathlon research: pacing, fueling and readiness. Practical steps, who it helps, and what to watch out for.
Open guideSources
- Effects of high-intensity interval and moderate-intensity continuous training on the anaerobic threshold of highly trained athletes in endurance sports: a systematic review with meta-analysis.
- A training goal-oriented categorization model of high-intensity interval training.
- Physiological adaptations and performance enhancement with combined blood flow restricted and interval training: A systematic review with meta-analysis.
- Meta-analysis of high-intensity interval training and alternative modalities for enhancing aerobic and anaerobic endurance in young athletes.
- Effects of Small-Sided Games vs. Conventional Endurance Training on Endurance Performance in Male Youth Soccer Players: A Meta-Analytical Comparison.
- The Effects of High-Intensity Interval Training on Basketball Players: A Systematic Review and Meta-Analysis.
- Effects of Precooling on Endurance Exercise Performance in the Heat: A Systematic Review and Meta-Analysis of Randomized Controlled Trials.
- How much does sleep deprivation impair endurance performance? A systematic review and meta-analysis.