Reproduce and reconcile the two-point critical swim speed calculation from one source-labelled completed 200 m and 400 m record without prescribing training.
A quick decision brief for this specific tool
One de-identified completed 200 m / 400 m record and basis; exact shared course, stroke, protocol, timing-method, accepted-trial and independent-summary provenance; strict completed 400 m, 200 m and independent same-record CSS pace clocks
Preserved provenance, parsed clocks, distance/time differences, reproduced two-point slope speed and pace, component paces, signed component-pace gap, labelled line intercept, independent CSS pace and signed arithmetic difference
Validate every source field and strict clock, calculate the 200 m distance difference and completed time difference, reproduce the two-point distance-time slope and pace, then compare the separately prepared CSS pace for the identical record
Choose your path
Reproduce the two-point distance-time model from one completed, source-labelled 200 m / 400 m record and compare an independently prepared CSS pace for that identical record without prescribing training or diagnosing physiology.
Catch a copied clock or pace-summary mismatch without receiving a workout target or physiological label.
Name the de-identified completed pair, course, stroke, protocol, timing method and accepted trials, then copy both clocks and the independent same-record CSS pace.
Sees the reproduced slope, pace and signed arithmetic difference while training, racing, health and safety decisions remain outside the worksheet.
Keep the two clocks attached to one evidence basis and expose every intermediate model value.
Select the record basis, preserve timing and inclusion provenance, inspect component paces, time difference, slope and intercept, then deliberately save or export the reviewed record.
Can reproduce the two-point line without relabelling its intercept as measured capacity or treating arithmetic agreement as protocol validity.
Retain unusual source values without an invented diagnosis or silent exclusion.
Enter the exact same-stroke/course pair, observe the signed 400 m-minus-200 m pace gap and model intercept, trigger a malformed-clock error, recover and return to the source evidence.
Receives transparent arithmetic and an explicit review boundary rather than a pacing, recovery, fitness or technique verdict.
Outputs and checklists are planning aids. Review the linked current authorities and the records, terms, instructions, and requirements that apply to your exact situation before a consequential decision.
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Copy the clocks only after the source has already grouped and accepted both completed trials. The worksheet does not infer whether different courses, strokes, timing systems, sessions or test protocols are comparable.
One record = same swimmer record + course + stroke + protocol + timing basis + accepted 200 m and 400 m trialsStrict clocks are converted to seconds, the 200 m distance difference is divided by the time difference, and the slope is converted to a pace clock. The line intercept is exposed as a model output rather than labelled as a measured physiological capacity.
Two-point speed = (400 m − 200 m) ÷ (T400 − T200); pace/100 m = 100 ÷ speedA zero difference confirms arithmetic agreement only. Research populations, protocol choices and model assumptions limit interpretation; official results, physiology, training, racing, open water, health and safety remain outside this worksheet.
Difference = reproduced CSS pace seconds − independent CSS pace secondsUpdated: August 2026
A de-identified 6:20 / 3:05 pair reproduces 1:37.50 per 100 m. The coach compares it with the separately prepared 1:37.50 summary and records zero arithmetic difference without assigning a workout.
The analyst preserves the exact course, stroke, timing and protocol record, reproduces both component paces and the two-point slope, then investigates a nonzero difference in the copied independent summary.
If the completed 400 m average pace is not slower than the 200 m average pace, the worksheet still exposes the signed component-pace gap and model intercept. The reviewer returns to the source record instead of receiving an invented diagnosis.
Critical swimming speed has been studied as the slope of a distance-time relationship. This worksheet reproduces the two-point line through one completed, source-labelled 200 m and 400 m protocol and compares an independently prepared CSS pace for the identical record. It preserves course, stroke, protocol, timing and trial-acceptance context; it does not turn the model output into a universal physiological threshold, workout prescription or race prediction.