Running Writings Lab

Ten scientific running calculators in one app: race pace, threshold (LT1 & LT2), critical speed, and adjustments for hills, heat, and wind. The same tools from Running Writings used by tens of thousands of runners, built from the ground up for iPhone and iPad. PACING & PREDICTION • Race Pace: finish times, splits, and pace conversions for any track, XC, or road distance, including custom distances. • Pace Percentage: calculate paces for Canova-style percentage-based workouts. • Power Law: predict your performances across a wide range of race distances using a power law model. THRESHOLD & PHYSIOLOGY • Critical Speed: fit a research-grade critical speed model using race or time trial performance. • CV, LT2, and VO₂max Pace: calculate physiologically based workout paces from any race distance 10k and under. • LT1 and Zone 2 Pace: get first lactate threshold and Zone 2 pace from a recent 5k…