Equilytics · Preusker Stable

CS / D′ Race Analyser

Critical Speed · Anaerobic Reserve · Real-Time D′ Balance · Kirby, Winn & Witt (2021)

Race Sim ▶

Race Times CSV — All Competitors

One row per horse per race. Columns: horse, distance (m), time (s). Each horse needs ≥ 3 distances spanning at least 400m for a reliable fit. Best (fastest) time at each distance is used automatically.

Drop race times CSV here or click to browse

horse, distance, time

Example:

horse,distance,time
Steparty,1200,68.53
Steparty,1400,81.00
Steparty,1600,93.67
Durham,1200,70.10
Durham,1400,82.50
Durham,1600,95.20
Durham,2000,120.80

Results

Horse	Source	CS (m/s)	CS (km/h)	D′ (m)	R²	Quality

CS & D′ — All Horses

RACE EST CS estimated from race time regression — use ≥3 distances over ≥400m range for best accuracy.

D′ negative / ⚠ — distance range too narrow or horse racing within aerobic capacity. Add a wider distance result.

Model: t = (1/CS) × d + D′/CS | D′ depletes when speed > CS, reconstitutes when speed < CS.

Upload race times CSV then click Calculate

Race Name

Race Distance (m)

Sectional Interval

Horses in Race

Horse	Src	CS	D′	D′ Left	Status
Load from Step 1 or add manually

200m Sectional Times

Enter each split (seconds) as the race runs. Press Enter to advance. Click Update after each entry.

Set up race first

Signals

Signals appear as horses deplete D′

D′ Balance — Live

0m completed

D′ remaining Depleted Bars drop when pace > CS · Recover when pace < CS

Race Pace vs Individual CS

Dashed lines = each horse's CS threshold

Free-Distance Handicap

Additional metres each horse can cover at CS pace using remaining D′ — Kirby et al. "free-distance" metric. Rank = predicted finishing order.

Horse	Src	CS (m/s)	D′ Left (m)	Free Dist (m)	Rank