🔬 Advanced Power Profiling
Historical Power Analysis: CP vs. 4DP
A rigorous exploration of mathematical power curves, asymptote modeling, and multi-dimensional athletic phenotype identification.
1. Two Complementary Perspectives on Fatigue
⚡ The Critical Power (CP) Model
A continuous hyperbolic curve derived by Monod & Scherrer. It states that all endurance power can be reduced to two physiological constants:
- CP (Watts): The aerobic power ceiling that can theoretically be sustained indefinitely without catastrophic lactate accumulation.
- W' (kJ): The fixed anaerobic work capacity available above CP.
🔬 4-Day Performance (4DP) Model
Rather than forcing a single curve across all durations, 4DP evaluates four independent physiological energy systems:
- NM (5 sec): Neuromuscular sprint power (ATP-PC phosphagen system).
- AC (1 min): Anaerobic Capacity (glycolytic system).
- MAP (5 min): Maximal Aerobic Power (cardiac stroke volume / VO2max).
- FTP (20 min): Functional Threshold Power (lactate clearance).
2. Rider Phenotype Classification
By normalizing your 5-second, 1-minute, 5-minute, and 20-minute power relative to body mass (Watts/kg), Ability.ICU categorizes your racing profile: