Methodology
How this calculator works
Critical Swim Speed Methodology
CSS is used as a threshold swim pace anchor. We present it as a training guide, not as a perfect prediction for every open-water condition.
- Use two maximal-effort swim performances to derive threshold pace.
- Explain pool-vs-open-water context before interpreting results.
- Keep training-zone language practical for triathlon sets and pacing work.
FAQ
Frequently asked questions
How often should I retest CSS?
Retesting every four to six weeks is usually enough during a focused block, provided the protocol stays consistent.
Can CSS stand in for open-water race pace?
It is a useful anchor, but open-water pacing still needs judgment for conditions, wetsuit use, and navigation cost.
Evidence
References
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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