About Run Analytics

Science-based running performance tracking, built by runners for runners

Our Mission

Run Analytics brings professional-grade performance tracking to every runner. We believe that advanced metrics like Critical Run Speed (CRS), Training Stress Score (TSS), and Performance Management Charts shouldn't be locked behind expensive platforms or require complex coaching software.

Meet the Developer

Albert Arnó

Creator

Albert Arnó created Run Analytics out of a personal need for better run tracking tools. As someone who enjoys running and has programming knowledge, he wanted an affordable, science-based analytics tool that wasn't tied to specific hardware or cloud platforms.

Why Run Analytics Was Created:

"I was frustrated by expensive subscriptions, vendor lock-in requiring specific devices, and lack of control over my own data. I wanted a tool that calculated CRS and TSS correctly, worked with any Apple Health-compatible device, and kept my data private. When I couldn't find it, I built it."

"Run Analytics combines sports science (based on Wakayoshi's CRS research and Coggan's TSS methodology) with modern iOS design and complete data privacy."

Our Principles

Science First: All metrics based on peer-reviewed research. We cite our sources and show our formulas.
Privacy by Design: 100% local data processing. No servers, no accounts, no tracking. You own your data.
Platform Agnostic: Works with any Apple Health compatible device. No vendor lock-in.
Transparency: Open formulas, clear calculations, honest limitations. No black box algorithms.
Accessibility: Advanced metrics shouldn't require a degree in sports science. We explain concepts clearly.

Scientific Foundation

Run Analytics is built on decades of peer-reviewed sports science research:

Critical Run Speed (CRS)

Based on Wakayoshi et al. (1992-1993) research at Osaka University. CRS represents the theoretical maximum running velocity sustainable without exhaustion, corresponding to lactate threshold.

Key Research: Wakayoshi K, et al. "Determination and validity of critical velocity as an index of running performance." European Journal of Applied Physiology, 1992.

Training Stress Score (TSS)

Adapted from Dr. Andrew Coggan's cycling TSS methodology for running. Quantifies training load by combining intensity (relative to CRS) and duration.

Key Research: Coggan AR, Allen H. "Training and Racing with a Power Meter." VeloPress, 2010. Adapted for running by Run Analytics using CRS as threshold.

Performance Management Chart (PMC)

Chronic Training Load (CTL), Acute Training Load (ATL), and Training Stress Balance (TSB) metrics. Tracks fitness, fatigue, and form over time.

Implementation: 42-day exponentially weighted moving average for CTL, 7-day for ATL. TSB = CTL - ATL.

Running Efficiency & Stride Metrics

Running efficiency metrics combining time and stride count. Used by elite runners and coaches worldwide to track technical improvements.

Standard Metrics: Running Efficiency = Time + Strides. Lower scores indicate better efficiency. Supplemented by Distance Per Stride (DPS) and Stride Rate (SR).

Development & Updates

Run Analytics is actively developed with regular updates based on user feedback and the latest sports science research. The app is built with:

Swift & SwiftUI - Modern iOS native development
HealthKit Integration - Seamless Apple Health sync
Core Data - Efficient local data storage
Swift Charts - Beautiful, interactive data visualizations
No Third-Party Analytics - Your usage data stays private

Editorial Standards

All metrics and formulas on Run Analytics and this website are based on peer-reviewed sports science research. We cite original sources and provide transparent calculations.

Last Content Review: October 2025

Recognition & Press

10,000+ Downloads - Trusted by competitive runners, masters athletes, triathletes, and coaches worldwide.

4.8★ App Store Rating - Consistently rated as one of the best running analytics apps.

100% Privacy-Focused - No data collection, no external servers, no user tracking.

Get in Touch

Have questions, feedback, or suggestions? We'd love to hear from you.