The Journal
What millions of race results and a testing lab can tell you about endurance. Every number is computed from real data; every method is named. Written by Andrea Scapini, data scientist and founder of labthlete.
The anatomy of an Ironman day: real swim, bike and run splits by finish time
Median swim, bike, run and transition splits for every finish-time bracket, from 1.9 million Ironman and 70.3 results in the Labthlete dataset. What a 12-hour Ironman or a 5:30 half actually looks like, leg by leg.
What is a good marathon time? Percentiles from 6.4 million finishers
Real percentiles by sex and age from 6.48 million marathon results in the Labthlete dataset: what beats the median, what puts you in the top 10%, and how rare sub-3 really is.
How a lactate test predicts your race time
From a step test to a finish-time prediction: what LT1 and LT2 actually are, how thresholds become a physics simulation, and why durability decides the last hour.