VO₂max values are estimates based on pace and heart rate. They reflect general trends, not laboratory measurements. Day-to-day fluctuations can be influenced by training, recovery, and external factors.

This chart shows three key indicators of the balance between training and recovery:
ATL reflects recent fatigue (short-term training load).
CTL represents long-term fitness, built up over weeks of training.
TSB indicates freshness: negative values mean accumulated fatigue, while positive values suggest better recovery and readiness to perform.