DFA1 (DFA alpha 1)

DFA alpha 1 is a heart rate variability (HRV) metric that allows tracking of the aerobic and anaerobic threshold.

DFA (detrended fluctuation analysis) alpha 1 measures the noise spectrum of your heart. As you ramp up the intensity of a workout and your heart has to work harder, the kind of noise - which the value of DFA alpha 1 represents - changes. Recent research has shown that DFA alpha 1 cross below 0.75 at your aerobic threshold and below 0.5 at your anaerobic threshold.

What is the benefit of using DFA alpha 1?

DFA alpha 1 might prove to be a ground-breaking advancement to correctly set our training zones and track fitness. It only requires you to use a MD KOLIBRI that tracks HRV. This way, you will be able to:

Determine your aerobic and anaerobic thresholds. For example, your aerobic threshold sets the upper bound of your Endurance training zone. It is important this bound is set correctly, to properly polarize your training, and actually take your easy activities easy for constructive training progression.

Avoid pitfalls of common test protocols. If you don't have access to a physiology lab, you can currently assess your aerobic threshold as the pace/power where you can comfortably hold a conversation. Since this method is obviously not very accurate, DFA alpha 1 presents an accurate but affordable and non-invasive alternative. For the anaerobic threshold, time trial fitness tests are hard to pace and lead to significant fatigue. On the other hand, ramp tests which take a percentage of your max power/pace as your anaerobic threshold depend on the ramp speed and often poorly correlate with your threshold.

Get high quality threshold data into MD KOLIBRI - all the time. Both thresholds provide defining information about your current fitness state. Therefore, assessing them regularly is crucial for our AI to determine which training leads to successful outcomes. We have automated these assessments from your HRV data to the point that you don't even have to do dedicated tests anymore.

Imagine being able to detect your fitness level during most activities that are hard enough to cross either threshold, without even thinking about fitness testing. This is what MD KOLIBRI does.

The following one figures show DFA alpha 1 vs heart rate for an activity with a ramp test from 16:40 to 33:20.

The main result: DFA alpha 1 drop below 0.75 at the aerobic threshold and below 0.5 at the anaerobic threshold.

Summary

DFA alpha 1 is an HRV based metric to determine your aerobic and anaerobic thresholds. It is easily accessible and non-invasive. Tracking DFA alpha 1 only used a MD KOLIBRI that records high quality HRV data.

DFA alpha 1 allows for You to track your fitness state consistently in an automated way without test protocols. More often and without the dread of fitness tests. Frequent automatic threshold detection leads to more data to correlate your training variables with your fitness state.

INTERPRETATION OF THE DFA1 INDICATOR IN CLINICAL PRACTICE.

As shown by independent clinical studies conducted in various clinics, it is recommended to control this indicator for patients who have suffered an acute myocardial infarction. DFA1<0.65 is the most powerful predictor of mortality [2] and depressed left ventricular function after acute myocardial infarction [3] (DFA1<0.85).

 1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4030044/

 2. https://pubmed.ncbi.nlm.nih.gov/12161220/

 3. https://pubmed.ncbi.nlm.nih.gov/10190395/