TC
    MyTriathlonCalculator
    Base Phase Training Guide

    Base phase

    Base Phase One-Pager

    The aerobic block on one sheet. Print it, stick it on the wall, stop guessing.

    The rules

    1. About 80% of volume sits in Zone 2: conversational pace, roughly 65–75% of max heart rate.
    2. The remaining 20% is technique drills, strides and occasional light tempo. Not intervals.
    3. Consistency beats any single session. Frequency is the adaptation.
    4. The point is not to be fast. It is to make the aerobic engine bigger before intensity lands on it.

    Base length and volume by distance

    Race distanceBase lengthWeekly hours
    Sprint4–6 weeks4–6 hours
    Olympic6–10 weeks6–9 hours
    Half Ironman10–14 weeks8–12 hours
    Full Ironman12–20 weeks10–16 hours

    Keep / drop

    Keep

    • Zone 2 volume across all three sports
    • Technique drills, swim especially
    • Foundational strength work
    • Strides to keep neuromuscular signals alive
    • A consistent weekly rhythm you can repeat

    Drop

    • Threshold and VO2 interval sets
    • Racing your training partners
    • Chasing pace on easy days
    • Big single weeks followed by nothing
    • Skipping the boring sessions

    The session menu

    Long easy ride
    The anchor session. Zone 2 throughout, extend duration gradually week on week.
    Long easy run
    Conversational the whole way. Add distance before you add pace.
    Technique swim
    Drill sets and short repeats. Base is where stroke faults get fixed cheaply.
    Strength
    Foundational, not power. Tendons and connective tissue adapt slower than muscle.

    Red flags

    • You can only say short phrases on an "easy" session. You are above Zone 2.
    • Weekly hours swing wildly. Durability comes from repetition, not heroics.
    • You are already doing interval sets. That is the build phase, and it is early.
    • Niggles in tendons or the achilles. Back off volume before it becomes a layoff.

    Next step

    Generate a periodised plan with your base block already sized to your race distance.

    Training Plan Generator

    Condensed from the full Base Phase Training Guide. mytriathloncalculator.com

    Get the other phase one-pagers

    Base, build, peak and taper: the printable sheets, plus the calculators as they ship.

    Free Tools
    Weekly Tips
    No Spam

    Unsubscribe anytime. We respect your privacy.