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Last reviewed: May 2, 2026Reviewed by: Manish Rajput

Methodology

How this calculator works

Triathlon Benchmark Guide Methodology

These benchmark guides use a hybrid model: reviewed public age-group trend anchors, percentile-style ability bands, and split-level context so athletes can compare total time and where that time is actually being won or lost across short- and middle-distance triathlon.

  • Use age-group benchmark anchors from reviewed public result summaries and official result ecosystems instead of one race only.
  • Keep age-group benchmarking separate from draft-legal elite racing because the competition environment is different.
  • Translate total times into swim, bike, run, and transition context so athletes can compare the real source of the gap.
  • Label ability bands as editorial benchmark ranges, not official qualifying standards.

FAQ

Frequently asked questions

Why is the first km off the bike so much slower?

The bike-to-run transition causes neuromuscular confusion, altered muscle recruitment, and glycogen depletion. Your legs need 1-5km to adjust from the cycling motion pattern to running gait.

How much does brick training help?

Regular brick training (1-2 sessions per week) can reduce the initial pace degradation by 30-45%. Even short 15-20 minute runs immediately after cycling provide significant adaptation benefit.

Does bike intensity matter for run performance?

Yes, significantly. Riding above 85% FTP causes disproportionally more run degradation due to increased glycogen depletion and neuromuscular fatigue. A 5% reduction in bike intensity can save 2-4% on run pace.

Evidence

References

  • Physiological and biomechanical adaptations to the cycle to run transition

    Millet & Vleck (2000), British Journal of Sports Medicine, 34(5)

  • Variability in energy cost of running at the end of a triathlon

    Hausswirth et al. (2010), International Journal of Sports Medicine, 31(09)

  • The effect of prior cycling on biomechanical and cardiorespiratory response profiles

    Hue et al. (1998), European Journal of Applied Physiology, 77(1)

This calculator provides estimates based on published exercise science research. Individual responses vary. These outputs are not a substitute for coaching, medical clearance, or your own experience. Always listen to your body and consult a qualified professional before making significant changes to your training.

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Plan 70.3 swim pace, bike speed, run pace, and transition budgets from a finish-time goal or known splits. Includes sub-8 through sub-4:30 benchmarks, what-if analysis, and pacing realism guidance.

Triathlon

Run Off the Bike Calculator

Predict how cycling fatigue will affect your run pace in a triathlon. See km-by-km pace degradation and when you'll settle into rhythm.

Your Inputs

Standalone Run Pace (/km)

First Km Pace

5:57/km

+8.2% slower

Average Pace

5:35/km

+1.4% vs standalone

Time Lost

+1:35

vs standalone run

Settling Distance

3 km

to reach target pace

Km-by-Km Pace Prediction

KmPaceDegradationVisual
15:57/km+8.2%
25:49/km+5.8%
35:44/km+4.2%
45:40/km+3%
55:37/km+2.2%
65:35/km+1.5%
75:34/km+1.1%
85:33/km+0.8%
95:32/km+0.6%
105:31/km+0.4%
115:31/km+0.3%
125:31/km+0.2%
135:30/km+0.1%
145:30/km+0.1%
155:30/km+0.1%
... 7 more km (pace converges to standalone)

Training & Racing Tips

  • Add 1-2 brick sessions per week (even 15-20min runs off the bike help adaptation).
  • Expect to settle into target pace around km 4.