SPORT::Running (SPOS.RUN)
= repeatable locomotion performance (speed × endurance × efficiency)
  under schedule + terrain + weather variability,
  while keeping tissue load (tendon/bone) below injury threshold.
Output is “pace reliability” + “finish reliability” + “training continuity”.

P3
- consistent weekly training (continuity)
- stable easy pace + stable form
- can execute workouts without “crash”
- durable tendons/shins/feet; niggles resolve quickly
P2
- workouts sometimes good, sometimes fail
- easy runs feel harder than they should
- minor niggles appear with mileage spikes
- pace fluctuates with sleep/stress
P1
- frequent missed runs
- persistent soreness (shin/foot/Achilles/knee)
- easy pace drifting slower, HR drifting higher
- workouts collapse early; mood/drive unstable
P0
- stress fracture / tendinopathy flare / chronic plantar fascia / severe burnout
- cannot train consistently; performance regression dominates

Z0 sleep debt + Z0 low fueling
→ Z1 mileage/intensity spike
→ Z0 calf/Achilles overload + Z0 bone stress accumulation
→ Z2 missed sessions + compensatory form
→ P2 → P1 → P0 (tendon injury or stress fracture)

TIMEFLOW::RUNNING_FUNCTION
T0 survival: pursuit, escape, messaging
T1 ancient state: courier systems, military scouting, endurance as readiness
T2 ritual + status: endurance feats, local races, training culture
T3 industrial: standardized events, clubs, records
T4 modern: scientific training (VO2max, thresholds), mass participation, pro circuits
T5 sensor era: load governance, injury prediction, individualized micro-cycles

RUN::Primitives
PR0 Aerobic base (easy volume tolerance)
PR1 Running economy (efficiency at submax pace)
PR2 Threshold capacity (sustained hard pace)
PR3 Speed / neuromuscular power (strides, short intervals)
PR4 Tissue durability (calf/Achilles/foot/shin, bone density, hip stability)
PR5 Pacing skill (not going out too fast)
PR6 Heat/humidity adaptation (context-dependent)

Z0::Top Failure Modes (Running)
FM0.R1 mileage spike (>10–20% suddenly)
FM0.R2 too much intensity (hard days too frequent)
FM0.R3 low energy availability (under-fueling)
FM0.R4 weak calves/hips → compensations (knee/Achilles/shin)
FM0.R5 poor footwear transition (sudden shoe drop change)
FM0.R6 ignoring early bone/tendon signals
FM0.R7 heat stress mismanaged (Singapore risk)
Z0::Sensor Pack (Minimum viable)
S0.R1 weekly mileage + longest run
S0.R2 hard-session count + spacing
S0.R3 session RPE × duration (simple load)
S0.R4 morning fatigue score (0–10) + sleep hours
S0.R5 pain map: shin/foot/Achilles/knee (0–10)
S0.R6 easy-run “talk test” (can speak full sentences?)
S0.R7 pace–HR drift on easy runs (if HR available)
Z0::Repairs
R0.R1 deload: reduce volume 20–40% for 5–10 days
R0.R2 intensity gate: max 2 hard sessions/week (often 1 for non-elite)
R0.R3 fuel baseline: carbs around training + daily protein floor
R0.R4 strength block: calf raises + hip stability 2–3×/week
R0.R5 shoe transition rule: change gradually over 3–6 weeks
R0.R6 heat protocol: slow pace + hydration + time-of-day adjustment

Z1::Failure Modes
FM1.R1 “every run is medium-hard” (no true easy)
FM1.R2 no recovery days after workouts
FM1.R3 workouts not matched to goal distance
FM1.R4 too many races used as workouts
FM1.R5 no injury contingency branch
Z1::Sensors
S1.R1 monotony: same type of run repeated
S1.R2 spacing: hard days separated by ≥48h (typical)
S1.R3 completion rate of key workouts
S1.R4 niggle incidence per 4-week block
Z1::Repairs
R1.R1 polarized structure: easy days truly easy
R1.R2 3-week build + 1-week deload (common safe pattern)
R1.R3 goal-specific workouts (5K vs 10K vs HM vs marathon)
R1.R4 race budget per season (cap)
R1.R5 injury branch plan: swap run → bike/swim while keeping aerobic load

Z2::Failure Modes
FM2.R1 youth specialization too early + over-racing
FM2.R2 no strength training culture
FM2.R3 staff fragmentation (coach vs physio)
FM2.R4 travel/schedule crush during exam periods
Z2::Sensors
S2.R1 dropout rate (especially after injury)
S2.R2 injury days lost / athlete / season
S2.R3 performance progression vs age band (watch early maturer bias)
Z2::Repairs
R2.R1 LTAD gates: technique + strength before high mileage
R2.R2 integrated S&C minimum standard
R2.R3 exam-season training template (maintenance mode)

Z3::Failure Modes
FM3.R1 unsafe heat policies
FM3.R2 excessive event density
FM3.R3 poor course safety (surface, crowding)
Z3::Sensors
S3.R1 heat incident rate
S3.R2 injury incidents at events
S3.R3 DNF rate spikes (signal pacing/heat mismatch)
Z3::Repairs
R3.R1 heat thresholds + mandatory hydration stations
R3.R2 calendar spacing rules
R3.R3 course safety standards

STATE::RUNNING
- Load L = weekly (RPE×minutes) or mileage
- Recovery Rec = sleep + fatigue score trend
- Tissue Risk TR = pain map trend (Achilles/shin/foot)
- Economy E = easy pace + perceived effort stability
- Race Reliability RR = pacing + finish stability
Phase Estimator:
IF L up AND Rec stable AND TR low AND E stable → P3 drift
IF TR rising OR Rec falling OR E worsening → P2/P1 warning
IF training continuity breaks (missed weeks) → P0 risk

1) 7–10 days: reduce load, keep easy running only
2) restore fueling + sleep window
3) reintroduce one quality session/week (short, controlled)
4) rebuild volume slowly (≤10%/week typical)
5) add strides + strength to stabilize tissue

Trigger: focal bone pain + pain worsens with impact + persists next day
1) stop impact running immediately
2) medical assessment
3) maintain aerobic via bike/swim
4) return-to-run ladder with gates (pain-free walking → jog intervals → continuous)
5) address root cause: load spike / low fueling / sleep

1) set realistic pace bands (A/B/C)
2) practice negative split in workouts
3) simulate race start control (first 1–2 km restraint)
4) lock 2 cues only: cadence + relaxed shoulders
5) post-race review loop (what broke, when, why)

CivOS Link:
- Running is the “minimal infrastructure sport”:
  scalable, low equipment, high public health leverage.
- At Z4: national fitness + school endurance culture.
- At Z5: mass events as cohesion rituals + tourism + identity projection.
- Risk: injury/burnout epidemics if load governance is absent.