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Race-Week Taper Formula + Carb Loading (Burke)

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 AI Fit Hub · AI Fit Hub Team
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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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FAQ

Questions people ask next

The short answers readers usually want after the first pass.

How much should you cut training volume during a race-week taper?
Reduce training volume by 41-60% of your peak, with most studies clustering around a 50% cut. Beginners can take more off (60-70%) while elites take less (30-40%). The key is to cut volume, not intensity: hold pace, power, or RPE at 90-100% of race intensity throughout the taper.
How long should the taper be for a marathon vs a half marathon?
Evidence supports roughly 8-14 days for a marathon, 7-10 days for a half marathon, and 4-7 days for a 5K-10K. The step-by-step guidance uses 14 days for a marathon, 10 days for a half, 7 days for a 10K, and 5 days for a 5K.
How much faster does tapering make your race, per Mujika and Padilla?
Mujika and Padilla's 2003 meta-analysis (n=27 studies) found that a 41-60% volume reduction over 8-14 days produces about a 3% performance improvement, and Bosquet et al. (2007) confirmed the ~3% figure. Cutting intensity instead of volume undoes most of that gain.
What does Burke et al. (2011) recommend for carb loading during the taper?
Burke et al. (2011) supports carb-loading at 7-12 g/kg of body weight per day for 1-3 days before the race. It pairs well with the taper because reduced training means less glycogen turnover, so the loaded glycogen stays in the muscle.
What is the most common tapering mistake?
Cutting intensity along with volume. Dropping volume to ~80% and intensity to ~60% creates a detraining mini-block rather than a taper, eroding fitness instead of just clearing fatigue. The taper should withdraw fatigue, not fitness, so keep the hard sessions and shed the easy bulk.

Sources & References

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