VO₂max, TSS and HRV: what the numbers mean
These metrics address different questions: VO₂max relates to aerobic capacity, TSS describes training load, and HRV reflects variation between heartbeats. They should not be treated as a single universal fitness score.
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VO₂max: a measurement or an estimate?
A calculated value is not a laboratory measurement. The INTERLIVE review reports substantial individual error in wearable estimates, limiting conclusions about a particular athlete. That research does not validate the TrainingPlatform AI calculation.
The project includes an experimental calculated VO₂max estimate for suitable running sessions. It is a separate estimate, not a relabelled value imported from a data source. Insufficient data may prevent an estimate. A continuous VO₂max history for every account is not promised.
TSS: load, not a workout quality rating
The metric’s developer defines TSS as an estimate of training load based on intensity and duration. This is a definition, not a comparison between services.
You can ask ChatGPT to explain TSS. That does not mean TrainingPlatform AI calculates it for every session or holds your TSS history. A personal comparison requires checking that the values exist.
HRV: variation between heartbeats
HRV describes differences in time between consecutive heartbeats. Australian Institute of Sport guidance places it in the context of training, stress responses and adaptation, with attention to measurement and interpretation.
Ask which HRV metric is available and for what period. “What does HRV mean?” is a conceptual question; “Why did my HRV change?” needs your records and context, not just a definition.
Questions that make an explanation checkable
These are example prompts, not a promise of an answer when records are missing.
- “Is this a measurement or a calculated estimate?”
- “Are there comparable records from the earlier period?”
- “Which limitations affect this conclusion about me?”
- “Explain it simply without prescribing my training.”
Availability and interpretation
The data available to you is confirmed when you connect. Explaining a term, accessing personal history and calculating a new value are different capabilities. AI can make mistakes; one number is not a diagnosis or a guarantee of performance.