A planning aid that estimates muscle-specific readiness based on training-load accumulation and decay over time.
The tracker uses an 'Equivalent Set' model. Research (e.g., Vieira et al., 2021) shows that training to failure (0 RIR) significantly elongates recovery time, sometimes by 24–48 hours, compared to submaximal training.
Train Libre applies this by weighting your working sets. A set at 0 RIR is flagged as high-fatigue, extending the estimated recovery window. The system also recognizes that compound movements like bench pressing create recovery pressure not just for the chest, but also for the triceps and front delts.
Different muscle groups recover at different rates. Larger, high-load groups (like the quads or lower back) are assigned longer base windows than smaller groups (like the biceps or calves).
Logged data is a proxy for training stress. The heuristic cannot 'see' external factors like sleep debt, nutritional deficiencies, or systemic life stress unless they are manually logged or integrated via health services.