Methodology & guide

Uploading a file

lanestats reads Lenex files — the standard results format produced by competition timing and meet-management software (file extension .lxf or .lef).

1. Export the meet results as a Lenex file from your timing or meet-management software.
2. Open the analyse page and select the file — the analysis runs in a few seconds.
3. Sign in to get the full per-lane breakdown, a PDF report and an email copy. Anonymous uploads only show a short summary.

What is hin-bias?

In a distance race (800 m or 1500 m) each swimmer covers many pool lengths, alternating direction. If the water moves along the pool, one direction is consistently helped and the other hindered. Hin-bias is the average time difference between the "odd" lengths (one direction) and the "even" lengths (the other) for a swimmer, with the first and last length excluded. A value near zero means no directional effect; a clear positive or negative value points to a current.

How the result is classified

For each lane we test whether the average hin-bias differs from zero. Across the pool we look at the trend from the inner to the outer lanes and the difference between the two outer lanes. The overall result is graded:

• Strong — outer-lane difference above 0.5 s with high statistical confidence.
• Medium — outer-lane difference above 0.2 s with statistical confidence.
• Weak — a small but visible tendency.
• None — no meaningful directional effect.

As a rough orientation, about 0.5 s of hin-bias corresponds to a current of roughly 2.6 cm/s.

Scientific basis

The method reproduces the peer-reviewed approach of Cornett, Brammer & Stager (2015), Medicine & Science in Sports & Exercise. lanestats applies the same statistical reasoning to competition split data.