1. Our Pacing Philosophy
Tri Splits was developed to provide triathletes of all experience levels—from first-time sprint novices to veteran double-Ironman competitors—with mathematically precise, bidirectional pacing models. Unlike generic timers, Tri Splits isolates transition segments (T1/T2) and models physiological metrics dynamically so you can visualize your complete race-day clock before toes touch the water.
2. Mathematical Pacing & Metrics Formulation
Our calculations adhere to rigorous physics-based principles and sports-science formulas to map endurance output levels across three distinct sports:
Calculated based on standard pace metrics (minutes per 100 meters or 100 yards). The model dynamically factors in the exact pool/open water conversion coefficient (m_yd ≈ 0.9144).
Modeled as a function of speed vs. duration. Transitioning speed (v_kph or v_mph) is mapped against typical aerodynamic resistance profiles to gauge the theoretical training stress and intensity.
Run pacing splits (minutes per kilometer or mile) are paired with cumulative fatigue coefficients. This highlights potential pacing degradation during the late stages of a multi-sport run.
3. Regulatory Compliance & Safety Standards
Tri Splits is calibrated around standard international triathlon guidelines, specifically incorporating the following rulesets:
- USAT (USA Triathlon) Wetsuit Rules: Under Article 4.9, wetsuits are fully legal for recreational age-groups up to 78°F (25.5°C). Above 84°F (28.9°C), they are strictly prohibited due to severe hyperthermia risk.
- Ironman & World Triathlon (WT) Standards: Age-groupers are permitted to wear wetsuits up to 76.1°F (24.5°C). Above this limit, athletes are classified as "wetsuit optional" (ineligible for division awards) up to 83.8°F, beyond which they are disqualified.
- Physiological Warnings: Our pacing models do not consider hydration deficits, extreme elevation gradients, or mechanical setbacks. Athletes must monitor heat index values and adapt pacing to local conditions to avoid cardiovascular shock.
4. Data Sourcing & References
Our calculations, wetsuit thermal guidance thresholds, and training stress factors draw directly from established endurance data sources:
- World Triathlon Competition Rules Manual (2025 Edition)
- USA Triathlon (USAT) Official Multi-Sport Rules
- Physiological Research on Aerobic Thresholds (Stephen Seiler et al.)
- Aerodynamic Modeling Standards for Human-Powered Vehicles (Wilson & Whitt)