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endurance Formula

Race-Week Taper Formula

Tapering reduces training volume sharply while keeping intensity high. Mujika & Padilla's 2003 meta-analysis (n=27 studies) found 41-60% volume reduction over 8-14 days produces a ~3% performance improvement — non-trivial in racing. Cutting intensity instead of volume undoes most of the gain. The taper is a withdraw of fatigue, not fitness.

4 VARIABLESPublished May 14, 2026Live Content
By Orbyd Editorial · AI Fit Hub Team
Best Next MovePlanning

Race-Week Taper Planner

Build a race-week taper using the Bosquet 2007 meta-analysis with distance-aware depth and weekly plan.

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On This Page

Formula 4 variables Worked example Variations

Education · Not medical advice. Output is deterministic math from your inputs.Editorial standardsSponsor disclosureCorrections

Formula

Copy the exact expression or work through it step by step below.

taper_volume(t) = peak_volume × (1 − r)^(t / τ) r = 0.5 (50% target reduction, fits 41-60% range) τ = days until race / ln(2) intensity kept at 90-100% throughout

Variables

peak_volume

Peak training volume

Highest weekly volume during build phase (km, hours, or distance equivalent). The taper starts from here.

r

Volume reduction target

Fraction of peak volume to remove by race day. 0.41-0.60 per meta-analysis. Most studies cluster at 50%. Beginners take more (60-70%); elites take less (30-40%).

τ

Taper time constant

Decay rate. Computed from total taper length. Most evidence supports 8-14 days for marathon, 7-10 days for half marathon, 4-7 days for 5K-10K.

intensity

Training intensity

Pace, power, or RPE. Hold at 90-100% of race intensity through the taper. Cutting intensity (the common mistake) erodes fitness; cutting volume preserves it while clearing fatigue.

Step By Step

  1. 1

    Identify peak weekly volume from your build phase (the highest week, not average).

    Marathon training peaked at 80 km/week.

  2. 2

    Choose taper length. Marathon: 14 days. Half: 10 days. 10K: 7 days. 5K: 5 days.

    Marathon → 14-day taper, starting 2 weeks out.

  3. 3

    Compute taper volume per week: 0.6 × peak, 0.4 × peak (race week).

    Week −2: 0.6 × 80 = 48 km. Week −1 (race week): 0.4 × 80 = 32 km.

  4. 4

    Keep intensity workouts. Hold marathon pace tempo + intervals through Week −2; do one short tempo Week −1.

    Week −2: 8 km @ marathon pace + intervals. Week −1: 4 km @ marathon pace + jog easy.

  5. 5

    Race week: 2-3 easy runs + 1 short tempo. Day −2: 4 km easy. Day −1: rest or 20-min jog.

    Mon easy 6 km, Tue tempo 4 km, Wed easy 5 km, Thu jog 30 min, Fri rest, Sat shake-out 3 km, Sun race.

Worked Example

Marathon runner peaking at 80 km/week, race in 14 days

Peak volume

80 km/week

Taper length

14 days

Reduction target

50%

Week −2 (days 14-8 out): 80 × 0.60 = 48 km. Intensity: marathon-pace tempo + 6×800m interval session. Week −1 (days 7-1 out): 80 × 0.40 = 32 km. Intensity: one short tempo + easy aerobic. Week of race: 80 × 0.20 = 16 km plus the race itself.

Expected outcome: 2-3% faster race time than no-taper baseline. Common mistake: cutting volume to 80% and intensity to 60% — that's a 'detraining mini-block' rather than a taper. Keep the spice, lose the bulk.

Common Variations

Linear taper (10-15% volume cut per day): older protocol, slightly inferior to exponential per Mujika's review. Use only if exponential schedule disrupts your existing routine.
Step taper (50% cut at once, hold for 14 days): suited to elite athletes already at peak fitness who need only fatigue clearance, not fitness preservation.
Active vs passive taper: active (maintain intensity, reduce volume) consistently outperforms passive (rest-only) in head-to-head studies. Passive only beats no-taper, not active.
Carb-loading often paired with taper. 7-12 g/kg/day carbs for 1-3 days pre-race (Burke et al. 2011). Combines well with volume reduction since reduced training means less glycogen turnover.

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Sources & References

General fitness estimates — not medical advice. Consult a healthcare professional for medical decisions.