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50K ultramarathon preparation

v1

A structured 20-week endurance program focused on aerobic base, muscular endurance, and tapering for a 50K race.

Available
ultramarathonrunningendurance50K

Get an AI coach that uses this skill

FitnessGrid is an AI coach that plans your week and adapts as you go. Install 50K ultramarathon preparation and your coach will follow this protocol every week, learn from what you actually do, and adjust on the fly.

  • Your coach builds the week from this skill
  • Adapts to your actual progress, not a static template
  • Free to start — no credit card, ~60 seconds to set up

Procedure

  1. Initial Assessment

    • Gather running history using get_user_history to verify a baseline of 15–20 miles per week (MPW).
    • Use compute_hr_zones to establish Zone 2 boundaries for "conversational pace" sessions.

  2. Phase 1: Base Build (Weeks 1–6)

    • Use create_week to initialize the schedule.
    • Plan Tuesday/Thursday Easy Aerobic runs in Zone 2.
    • Plan Saturday Long Runs, increasing volume by 5–10% weekly.
    • Schedule a deload on Week 4 or 5: reduce total volume by 30–50% while maintaining run frequency.

  3. Phase 2: Strength & Vert (Weeks 7–12)

    • Introduce Wednesday "Strength/Hills" sessions.
    • Coaching Cue: "Drive through the glutes on climbs."
    • Continue 5–10% weekly volume progression.
    • Schedule a deload on Week 8 and Week 12.

  4. Phase 3: Peak Volume (Weeks 13–17)

    • Target a minimum of 30 MPW for finishers and >50 MPW for performance.
    • Scale Saturday Long Runs toward a peak of 20 miles or 4-5 hours.
    • Use create_workout for Sunday recovery runs to build back-to-back durability.
    • Coaching Cue: "Time on feet > Pace. Practice fueling."

  5. Phase 4: Taper (Weeks 18–20)

    • Week 18: Reduce volume to 40–60% of peak using update_workout.
    • Week 19: Reduce volume to 20–30% of peak.
    • Week 20: Reduce volume to <20% (excluding race).
    • Maintain run frequency and include short intensity bursts (e.g., 1x5 min tempo) to prevent neuromuscular decay.

  6. Ongoing Quality Control

    • Every 4th week, apply the deload rule (30–50% reduction).
    • Monitor "grey zone" fatigue; ensure easy runs stay conversational.
    • Use the "3/4 Strategy" for advanced runners: first 75% easy, final 25% at steady-state.