In keeping with our upcoming review of "whats new" in DFA a1 related exercise topics, I wanted to consolidate a cross comparison listing of current apps that will display this metric either on the Web or in real time on smart devices. I will continue to add/subtract based on features, issues and programming changes made. Most of the apps have separate posts except for the new iOS beta app. Below the matrix listing I will make some personal comments about each app as well. It was interesting to go back to my first impressions of many of the app's initial agreement with Kubios (which is what we use in published studies) - they were uniformly not good. However with cooperative developers, excellent agreement to Kubios was achievable. Many personal thanks to those individuals (you know who you are) for being open to constructive criticism.
Runalyze - An excellent web based app that does it all - will track power, muscle O2, Core body temp, HRV etc. Great development team willing to adapt and adjust the product per user feedback. It allows one to determine where to set the stop, start timing points for ramp analysis. Csv download contains DFA a1, power, HR for easy Excel analysis. Artifact percentages are displayed for each 2 minute measurement window.
AIEndurance - Another excellent web based app. The focus here is perhaps more DFA a1 vs power/HR related than Runalyze. There is automatic calculation of threshold values if a progressive HR/power rise is noted during the first 30 minutes. In addition, the app will keep track of historical trends of the a1/power relationship to determine degrees of baseline fatigue (inappropriate low a1 at warmup power) as a measure of readiness. The app will also track the a1:power relationship during a longer session as a measure of exercise fatigue/durability. These are handy observations to have and our group is in the process of further exploration/validation of this concept. The development team is very willing to take suggestions to improve the product.
Fatmaxxer - Although android only, as near perfect a monitoring app that I could hope for. Why - excellent Kubios agreement, nice graphical display of pertinent data (including artifacts), signal strength of the ECG waveform for optimal belt positioning and perhaps most important of all - ECG tracing snips pre/port each artifact detected. That one feature alone may potentially save a life someday for detecting a serious arrhythmia. Designed by an enthusiastic, talented developer who is interested in making a quality product that is free of charge. Finally, the RR output file is "unfiltered" meaning that it contains the raw RR data for potential Kubios analysis. This a good tool for researchers looking to collect HRV for later Kubios import, while also getting realtime feedback on a1 and signal strength for optimal belt position.
Alpha One Endurance - This is an app designed by Ash Burrows and more info can be found here. Although I do not have detailed specs at this time, the app uses Kubios preprocessing methodology and testing so far has shown excellent agreement to Kubios. Further review and comments pending. It is very welcomed since there is a current lack of an appropriate iOS based DFA a1 app.
alphaHRV - The app that I thought would be impossible to create (I'm happy to be wrong) - an accurate, realtime a1 display for Garmin watches and head units (without a smartphone being needed). Although it is using an alternate method of preprocessing and a measurement window of 200 beats (instead of 2 min), the data is close to that of Kubios and updates each second (user defined). A masterwork of programming and imagination indeed! Artifact % is displayed and there is a 2 min running graphical display of a1 on device. Garmin fit files will contain this data so you can extract for further analysis. Garmin Connect treats this like any data field (with artifacts showing as well). The development team is helpful, motivated and willing to adjust the product as needed. Please see my review for why we can't expect precise Kubios agreement, but IMO, this is close enough for our purposes.
HRV logger - The first app for realtime a1 tracking. Unfortunately, it suffers from inherent limitations in recalculation ability (stuck at 120 sec) and non optimal preprocessing that may lead to poor a1 agreement to Kubios. The app was designed as an add on for an already mature product as opposed to Fatmaxxer, alphaHRV and Alpha One Endurance which were created solely as an a1 tracking app. An analogy for this app is that of the first cellphones. I remember my first "bag" phone, a real game changer for a busy doctor - I didn't have to stop at a pay phone (yes really) to answer calls after my pager went off. So yes, the bag phone was great in 1988. But in 2022, we can (and should) do better. This app has not been updated and the developer has lost interest in DFA a1, making improvements in programming, interface, and Kubios agreement unlikely. As they say, "the right tool for the right job".