What contact and flight times and step rate does an open running study give, and how many frames is the flight phase?

Partially verified: the curator re-read none of the cited sources; S4, S5 rest on the producer's pinned reading. A PLoS ONE study with 1000 Hz high-speed video reports, for runners at 3.25 m/s on a treadmill, contact time 0.267 s, flight time 0.093 s and 166.8 steps/min. At 24 fps a step is about 8.6 frames with about 6.4 contact and 2.2 flight frames (author arithmetic). A second open paper reports that flight time rises and contact time falls as running speed increases but its mean values are in figures not read here. Curator qualifications: Partially verified: the curator re-read none of the cited sources; S4, S5 rest on the producer's pinned reading. Curator GET 2026-10-23 of the sources not re-read (mechanical source evidence, not semantic verification): S4: HTTP 200, bytes equal to the producer pin; S5: HTTP 200, bytes equal to the producer pin. Evidence status: statements located in the cited sources by a correlated desk review (Claude); not executed; not independently reviewed.

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