Phase 001 · Aerobic Foundation

Engine of Engines — Full Aerobic Base

6 weeks · once daily · low-impact dominant · Zone-2 disciplined · built on the Norwegian polarized model and Inigo San Millán's Zone 2 science. Evidence-first. Hip-surgery-aware. The goal is the biggest aerobic engine possible before any sharpening in Phase 002.

HR anchor Z2 ≤146 bpm · aim 125–140 FTP 270W · C2 BikeErg Z2 ≈ 150–195W Wk 1–2 SkiErg + C2 BikeErg Wk 3+ RowErg added Echo/Assault Bike Saturday BFT Tysons only Zero running this block — 100% low-impact StairClimber optional Z2 sub any session

Today's session

Block start date (Monday of Week 1)

Why this works

Phase 001 is deliberately monotonous in the best sense: a large volume of truly easy aerobic work, almost entirely low-impact, with intensity on a tight leash. This is the engine every later quality phase is built on. The science is unambiguous — see the Science tab for citations.

The Norwegian / Polarized Model

  • ~85–90% low intensity, ~10–15% moderate, <5% high. Stephen Seiler's research across elite endurance athletes consistently shows this "polarized" distribution outperforms spending most time at threshold. (Seiler & Kjerland 2006; Stöggl & Sperlich 2014).
  • Zone 2 is the engine room. Inigo San Millán's lab work shows sustained Z2 training maximises mitochondrial density, fat oxidation, and lactate clearance — the exact machinery Hyrox burns. It's slow to adapt and impossible to rush.
  • Frequency over intensity. More moderate sessions, fewer brutal ones. The aerobic system responds to repeatable, consistent stimulus — not occasional heroics.
  • Aerobic threshold touched, never hammered. From Week 3, short controlled Z3 touches appear (RPE 5–6). Threshold and VO2 intervals are a Phase 002 problem.

Equipment progression — the why

  • Weeks 1–2: SkiErg + C2 BikeErg only. Zero hip-joint impact. Both transfer directly to Hyrox SkiErg and BikeErg stations. Builds erg efficiency and Z2 discipline before adding a third modality.
  • Week 3+: RowErg introduced on Wednesdays and Fridays. Hip flexion demand at the catch is greater than ski or bike — it enters at low volume (20 min) once Z2 discipline is established and the hips are 2 weeks further into load tolerance.
  • No running this block. Zero impact. The entire aerobic base is built through ergs — directly translating to Hyrox stations. Running returns in Phase 002 once the base and hip load tolerance are confirmed.
  • StairClimber: optional Z2 substitute any session. Upright posture, deliberate full step, no railing lean. HR 125–140. Excellent alternative for variety or when a machine is unavailable. Hip check: shorten stride if flexion at the top pinches.
  • Echo/Assault Bike: Saturday at BFT Tysons only. 1×/week max. All other bike work = C2 BikeErg at home. Echo bike RPE runs hotter (fan resistance), so Saturdays are the circuit/functional day.

Strength + PT integration

Hip-stability work appears 2×/week (Tuesday + Thursday), 15–20 min, bolted onto the aerobic session. This is the bridge between physio rehab and training: building the glute and hip stability needed for future running and heavy ergs, without competing with the aerobic adaptation. Upload your clinical PT notes in the PT Notes tab to add your surgeon/physio-specific exercises.

Measuring the engine growing

W1 vs W6
BikeErg @ HR 140 · more watts = bigger engine
Drift %
Less cardiac drift over 30 min = aerobic durability
Feel
Same pace, lower HR as weeks progress = adaptation

Strava logging

Your Strava is connected (read). Log sessions manually on Strava — pick the right activity type (NordicSki=SkiErg, VirtualRide=BikeErg, Rowing=RowErg). Your Z2 discipline will show as low cardiac drift in the Strava HR graph — that's the training effect made visible. The Strava MCP currently reads your data; push/create is not available in this integration but manual logging is fast.

Evidence base

Every programming decision is anchored to peer-reviewed literature or high-quality applied sport science. Below are the key pillars — clickable references where available.

Polarized Training Distribution

The 80/20 rule — why almost everything is easy

Stephen Seiler's analysis of elite XC skiers, cyclists, runners, and rowers consistently showed they accumulated ~80% of training at low intensity and ~20% at high intensity — almost nothing at threshold. This "polarized" distribution beat threshold-dominant models in head-to-head trials.

Seiler & Kjerland (2006) Scand J Med Sci Sports Stöggl & Sperlich (2014) Front Physiol Seiler (2010) Int J Sports Physiol Perform Stephen Seiler, U of Agder

Zone 2 / Lactate Threshold 1

Why Zone 2 builds the engine

Inigo San Millán's research demonstrates that sustained Zone 2 training (below LT1 — the first lactate inflection point) is the primary driver of mitochondrial biogenesis, fat oxidation capacity, and metabolic flexibility. Elite athletes oxidize fat efficiently at speeds/powers that recreational athletes cannot — because they have spent thousands of hours in Z2. The adaptation is slow (weeks–months) and cannot be accelerated by going harder.

Your HR Z2 ceiling (146 bpm) corresponds to approximately your LT1 — confirmed by your manually-set zones and 43:00 10k reference. The aim of 125–140 keeps you in the mitochondrial adaptation window without drifting into lactate accumulation.

San Millán & Brooks (2018) Front Physiol Achten & Jeukendrup (2003) Sports Med — HR monitoring Iñigo San Millán, Stanford / CU Boulder Peter Attia — practical Z2 application

Cardiac Drift & Aerobic Decoupling

The measurement that proves the engine is growing

During a steady Z2 effort, HR naturally drifts upward over time (cardiac drift) while power/pace holds. Aerobic decoupling — the % divergence between HR and pace/power — is a reliable marker of aerobic fitness. As base fitness improves, drift decreases. The Week 1 vs Week 6 BikeErg test at HR 140 will quantify this directly: more watts, less drift = larger engine.

Achten & Jeukendrup (2003) Sports Med Edwards (1993) — HR training literature

Return to Run After Hip Arthroplasty

Why low-impact dominant, and when to introduce impact

Clinical consensus after total/bilateral hip arthroplasty supports low-impact aerobic training (cycling, swimming, elliptical) from approximately 6–12 weeks post-op, with a graduated return to running typically gated at 12–20 weeks depending on prosthesis type and surgeon protocol. The 10% weekly volume rule for running load is derived from overuse injury prevention literature (Gabbett load management framework; van Gent et al. 2007 on running injuries).

Your SkiErg + BikeErg-dominant approach is precisely aligned with post-THA best practice: large aerobic adaptation stimulus with near-zero hip joint compressive load. Run/walk re-introduction with HR-gated intensity prevents overloading healing tissue.

Aarons et al. — Return to sport after THA van Gent et al. (2007) Br J Sports Med — run injury prevention Gabbett (2016) Br J Sports Med — training load Hip pain = stop signal. Non-negotiable.

Norwegian Double Threshold (context for Phase 002)

Why we're not doing this now

The Norwegian model used by Jakob Ingebrigtsen and elite XC skiers includes two daily threshold sessions — but on a base of years of polarized training and high aerobic capacity. The double-threshold sessions work because the engine underneath them is enormous. Phase 001 builds that engine. Trying to do threshold work without the base is like running a turbocharger on a stock engine — the gains don't stack.

Marius Bakken — Norwegian running methodology Tjelta et al. (2014) Int J Sports Sci Coaching

WOD Science & Evidence-Based Functional Fitness

Applied programming principles

WOD Science applies peer-reviewed exercise physiology to functional fitness programming. Key principles aligned with this plan: progressive overload within modalities, specificity of adaptation (ergs → erg stations), the importance of aerobic base for repeated high-intensity work capacity, and the superiority of well-periodized base phases over year-round high-intensity training.

The Hyrox-specific application: a deeper aerobic base means faster recovery between stations, better ability to hold run pace after functional efforts, and lower RPE at race pace — all of which translate to faster times.

WOD Science — evidence-based CrossFit/functional methodology Helgerud et al. (2007) Med Sci Sports Exerc — aerobic base quality

Run Cadence & Hip Mechanics

Why quick, quiet steps matters post-surgery

Higher cadence (≥170 steps/min) reduces ground contact time, vertical oscillation, and hip extension demands — all relevant post-THA. Research shows that increasing cadence by ~5–10% reduces loading rate and patellofemoral stress. For your return-to-run, this is not just a performance cue — it's a load management tool for the hips.

Heiderscheit et al. (2011) Med Sci Sports Exerc Hafer et al. (2015) — cadence and joint loading

Your zones — Phase 001 working ranges

From your manually-set Strava HR zones and FTP 270W (real, not estimated). Run zones derived from your 43:00 10k RacePace reference. Post-surgery: HR leads everything. Let pace and power settle where HR sits — they'll improve as the engine grows.

ZoneHR (bpm)RPE / feelC2 BikeErgRun paceUse in Phase 001
Z1 Recovery <1201–2 · effortless<150W>5:45/km Warm-ups, flush spins, recovery days
Z2 Aerobic Base 120–146 (aim 125–140) 3–4 · full sentences, "all day" 150–195W5:00–5:45/km The block. ~85% of all work.
Z3 Aerobic Thr. 147–1655–6 · "comfortably uncomfortable" 196–243W4:23–5:00/km Controlled touches only, Wk 3–6
Z4–Z5 166+7–10 · hard244W+<4:23/km Not in Phase 001. Phase 002 territory.

Equipment zones

MachineZ2 targetStrava log asNotes
C2 BikeErg150–195W · 85–95 rpmVirtualRideHome. Primary modality Wk 1–2.
C2 SkiErg~2:30–2:50/500m at Z2 HR · 26–30 spmNordicSkiHome. Wk 1–2 alongside BikeErg.
C2 RowErg~2:05–2:20/500m at Z2 HR · 22–26 spmRowingIntroduced Wk 3. Hip flexion — check pain.
Echo/Assault BikeHR 125–140, watch watts (they're air resistance)VirtualRideBFT Tysons only · Saturday · 1×/week.
StairClimberHR 125–140 · full step · no railing leanEllipticalOptional Z2 sub any session.
RunningNot in Phase 001. Phase 002 territory.

PT & Hip Clinical Notes

Paste your PT clinical notes, emails, or exercise prescriptions below. They're saved privately in this browser only — never sent anywhere. Once saved, I'll surface the relevant exercises in each session's hip note.

Click to paste notes, or drag a .txt file here

Standard hip-stability protocol (Phase 001)

This is the evidence-based default integrated into Tuesday + Thursday sessions. Upload your own PT notes above to layer in surgeon/physio-specific work.

Hip Stability Circuit · 2×/week · ~15 min

  • Banded clamshells 3×15 each side · medium band · controlled tempo
  • Side-lying hip abduction 3×12 each side · slow & controlled
  • Supine glute bridge 3×15 · hold 2s at top · progress to single-leg as tolerated
  • Dead bug 3×10 each side · maintain neutral lumbar spine
  • Standing hip flexor stretch 3×45s each side · couch stretch or kneeling
  • Pallof press 3×10 each side · anti-rotation core
  • Heel slides 2×15 · controlled hip flexion range check — stop at any pinch

Science: hip abductor strength is the primary predictor of run mechanics quality and is directly implicated in post-THA gait normalisation. (Bohannon 1997; Rasch et al. 2010 — hip muscle strength after THA).

Progress

Progress saved locally in this browser.