FSHP Academy
Hybrid Training — all lessons

Module 1: The Hybrid Paradigm

The rise of hybrid trainingWhy “strength vs endurance” is outdated: the interference effectTraining order, intensity and recovery timing

Module 2: Energy Systems in Hybrid Performance

Aerobic vs anaerobic systemsZone 2, threshold, VO₂ max and alactic workConditioning design principles

Module 3: Strength for Hybrid Athletes

Movement selection: barbell, dumbbell, kettlebell, bodyweightManaging volume, intensity and recoveryHow strength influences endurance

Module 4: Conditioning & Endurance

Long slow distance vs HIITThreshold and tempo trainingHybrid running strategiesConditioning periodisation models

Module 5: Program Design & Periodisation

Goal-based biasing (strength vs endurance)4-week, 12-week and yearly structuresDaily undulating periodisation in hybrid trainingConcurrent training template

Module 6: Case Studies

HYROX case studies and applicationsTactical athlete programme (12 weeks)Competition prep: HYROX, Yodha Race and more

Zone 2, threshold, VO₂ max and alactic work

The intensity domains used in hybrid conditioning — moderate (Zone 2), heavy/threshold, severe (VO₂ max) and alactic — with markers and prescription methods.

Intermediate Evidence: Strong evidence 3 min read Reviewed 2026-10-31 Status: draft

Learning objectives

  • Define exercise intensity domains and their boundaries
  • Relate domains to zones, lactate and critical power
  • Prescribe work in each domain
  • Recognise limitations of zone methods

Before this lesson

Why this matters

Hybrid athletes need a common language for intensity to design balanced conditioning.

Blood lactate response to incremental exercise Blood lactate stays close to resting values (about 1 millimole per litre) at low running speeds, begins to rise at the first lactate threshold (LT1), and rises steeply beyond the second threshold (LT2, close to maximal lactate steady state). A fixed 4 millimole line is shown for comparison; it does not represent the same intensity for every athlete. fixed 4 mmol·L⁻¹ (“OBLA”) LT1 LT2 ≈ MLSS Moderate domain Heavy domain Severe domain 8101214161820 0246810 Running speed (km·h⁻¹) — illustrative trained runner Blood lactate (mmol·L⁻¹)
Figure 1. The lactate curve and threshold landmarks. — Original diagram, FSHP Academy (schematic, not to scale).

Domains

DomainMarkerFeelExample
Moderate (“Zone 2”)Below first thresholdConversational, RPE 2–345–90 min easy run/bike
Heavy (threshold)Between first threshold and critical powerComfortably hard, RPE 5–63 × 10 min tempo
Severe (VO₂ max)Above critical powerVery hard, RPE 8–95 × 3 min, equal rest
Alactic/extremeMax sprintAll-out8 × 8 s sprints, 2 min rest

Critical power/speed defines the heavy–severe boundary [poole2016]. Fixed percentages of max HR or VO₂ max can misclassify intensity — individualise [jamnick2020]. Endurance athletes typically spend most time in low intensity [seiler2010].

Common mistakes and misconceptions

Case study

A hybrid athlete’s “easy” runs were at tempo pace. After a threshold test, she slows easy runs by 45 s/km; her interval quality and recovery improve within weeks.

Further learning: video lessons

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Practical demo needs verification — opens a YouTube search

Zone 2, threshold, VO₂ max and alactic work

hybrid and endurance coaches (search)

You will understand: zone 2, threshold, vo₂ max and alactic work

Why: Practitioner content; verify the specific video and its evidence.
Technical needs verification — opens a YouTube search

Concurrent training research explained

sports science educators (search)

You will understand: evidence on concurrent training

Why: Evidence summary.

Knowledge check

Knowledge check · 0/5

1. The moderate domain lies…

Answer B. Steady, conversational.

2. Critical power marks…

Answer B. Poole et al. (2016).

3. VO₂ max intervals typically last…

Answer B. Severe domain.

4. Alactic work refers to…

Answer B. Phosphocreatine system.

5. Jamnick et al. (2020) caution that…

Answer B. Individualise.

Short-answer & application questions

  1. Map your zones from a recent test.
  2. Design one session in each domain.
  3. Explain Zone 2 to a client with RPE and the talk test.

Key takeaways

  • Intensity domains: moderate (below first threshold), heavy (between thresholds), severe (above critical power), extreme.
  • Zone 2 roughly corresponds to the moderate domain — easy conversational effort.
  • Critical power/speed marks the boundary to severe intensity.
  • Zone systems differ; individualise with testing, HR and RPE.

Connected topics

hybrid training

Conditioning design principles

hybrid training

Threshold and tempo training

physiology

VO₂ max

References

  1. Poole DC, Burnley M, Vanhatalo A, Rossiter HB, Jones AM (2016). Critical power: an important fatigue threshold in exercise physiology. Medicine & Science in Sports & Exercise, 48(11):2320–2334. Narrative review check pending
  2. Jamnick NA, Pettitt RW, Granata C, Pyne DB, Bishop DJ (2020). An examination and critique of current methods to determine exercise intensity. Sports Medicine, 50(10):1729–1756. doi:10.1007/s40279-020-01322-8 Narrative review check pending
  3. Seiler S (2010). What is best practice for training intensity and duration distribution in endurance athletes?. International Journal of Sports Physiology and Performance, 5(3):276–291. doi:10.1123/ijspp.5.3.276 · PubMed 20861519 Narrative review verified

Educational content only — not medical advice. Consult a qualified clinician for diagnosis or treatment.