Polarised 80/20 Microcycle Designer

Convert your available training hours into a polarised 80/20 split that respects your preferred session lengths. The planner breaks down low- versus high-intensity hours, rounds them to practical session counts, and shows how taper weeks reshape the block’s total load and acute-to-chronic ratio.

Total number of training hours you can realistically commit every week.
How many weeks this microcycle template will run before you reset or peak.
Percentage of weekly time you want at threshold/VO₂max. Enter 20 for a classic 80/20 split.
Optional. Defaults to 0.75 h intervals if left blank.
Optional. Defaults to 1.50 h aerobic sessions when blank.
Optional. Defaults to 0. Enter how many taper weeks run at 60% load before race week.

Volumes assume steady availability and do not account for illness, travel, or fatigue markers. Adjust using HRV and perceived exertion before executing the plan.

Examples

  • 9.5 h/week for 12 weeks, 20% high intensity, 0.75 h high sessions, 1.5 h low sessions, 1 taper week ⇒ Weekly target 7.60 h low (5 sessions) and 1.90 h high (3 sessions), keeping an 80/20 split. One taper week at 60% yields 88.16 h low + 22.04 h high (110.20 h overall). ACWR ≈ 1.03.
  • 6 h/week for 8 weeks, 15% high intensity, default session lengths, no taper ⇒ Weekly target 5.10 h low (3 sessions) and 0.90 h high (1 session). Block total 40.80 h low + 7.20 h high (48.00 h overall). ACWR ≈ 1.00.

FAQ

How should I round the session counts?

Use the displayed rounded counts as a baseline, then adjust to your actual weekly schedule. For example, combine two shorter recovery runs into one cross-training session if needed.

Can I bias more threshold work during race prep?

Increase the high-intensity share field from 20% to 25–30% for short blocks, and reduce taper weeks to maintain overall freshness.

What if I include strength training?

Add the strength time to your weekly availability and treat lifting sessions as high intensity if they meaningfully tax recovery; otherwise, leave them in the low-intensity bucket.

Additional Information

  • The polarised 80/20 framework keeps roughly 80% of training time below lactate threshold and 20% at or above it.
  • Acute:Chronic workload ratio compares the planned week with the rolling average load of the block to flag spikes.
  • Taper weeks apply a 40% reduction to both low- and high-intensity volume while keeping the session ratio intact.

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