Although many prior posts in this blog assumed DFA a1 reached VT1 at about .75, until yesterday, no published peer reviewed data existed to verify this concept. However, we now have a high quality validation study published in Frontiers in Physiology confirming that. Before getting into a brief summary of our findings I would like to thank both my co authors, the Frontiers reviewers (Drs Lars Brechtel, Daniel Boullosa) and Editor (Dr Clint Bellenger). We were very fortunate in having reviewers who were both knowledgeable in HRV and exercise physiology (which is not a common skill set) who understood what we were trying to accomplish. It was an incredible experience (and much fun) to work with Dave, Nick, Olaf and of course my very good friend Thomas.
The full version is in the "production department" at this point, therefore I need to wait until it is in final form to get into more detail, review some interesting figures, stats and correlations with gas exchange. However, the abstract should provide more assurance for using DFA a1 to help determine your VT1 and assist with the low intensity portion of zone training.
In the meantime, the following posts should help guide implementation of using the index in practical terms:
Heart rate variability during dynamic exercise
- Firstbeat VO2 estimation - valid or voodoo?
- Heart rate variability during exercise - threshold testing
- DFA alpha1, HRV complexity and polarized training
- HRV artifact avoidance vs correction, getting it right the first time
- VT1 correlation to HRV indexes - revisited
- DFA a1 and Zone 1 limits - the effect of Kubios artifact correction
- HRV artifact effects on DFA a1 using alternate software
- Published article on DFA a1 and Zone 1 demarcation
- DFA a1 vs intensity metrics via ramp vs constant power intervals
- DFA a1 decline with intensity, effect of elevated skin temperature
Correlation Properties of Heart Rate Variability (DFA a1): A New
Biomarker for Intensity Distribution in Endurance Exercise - Frontiers in Physiology
- Movesense Medical ECG V2.0 Firmware brief review
- Movesense Medical ECG - improving the waveform and HRV accuracy
- DFA a1 and the aerobic threshold, video conference presentation
- DFA a1 - running ramp and sample rate observations with the Movesense ECG
- DFA a1 calculation - Kubios vs Python mini validation
- Real time Aerobic thresholds and polarized training with HRV Logger
- Active Recovery with HRV Logger
- DFA a1 and exercise intensity FAQ