Heart Rate Variability – Part 3: Available Tools

Now that we’ve covered what heart rate variability (HRV) is and how to interpret it, let’s take a look at some of the hardware and software tools that are available to help you make use of HRV data.

A variety of hardware and software tools are available for athletes and coaches who are interested in using HRV to help guide their training plans.

• Omegawave
  In triathlon circles, Omegawave is probably the most familiar name in HRV technology. The system for individual athletes includes a heart rate monitor/chest strap that communicates by Bluetooth with a subscription-based mobile software app. The device is used to make a 2-minute recording of the resting HRV. Then, using proprietary algorithms (invisible to the user), the software calculates an index of cardiac readiness along with cardiac readiness elements that include “stress,” “recovery pattern,” and “adaptation reserves.” The software also generates a table of appropriate training zones based on heart rate and an index of aerobic readiness. Omegawave touts the utility of its system in helping athletes determine their “readiness to train.” I’ve used the Omegawave system and found it very easy to use. The downside, of course, is that it’s a bit of a black box. Athletes just don’t know exactly what’s being measured or reported.
• BioForce HRV
  Like the Omegawave system, the BioForce system includes a mobile app together with web-based software that is designed to work with a heart rate monitor (such as Polar). An index of HRV, again not explicitly defined, can be measured during a 3-minute rest period and stored for comparison with succeeding days. Included with the system is a book, “The Ultimate Guide to HRV Training,” where training recommendations are based primarily on the day-to-day changes in HRV. Like the Omegawave system, the user is blinded to what exactly is being calculated or derived for the HRV index.
• Ithlete
  Another similar product is the ithlete HRV system which uses a proprietary heart rate monitor or finger probe, together with a mobile app, to calculate an index of HRV. ithlete offers the advice that a large drop in HRV from one day to the next should prompt the athlete to back off from training. Like the Omegawave and BioForce systems, the user is blinded to what exactly is being calculated.
• Heart Rate Monitors
  Some heart rate monitors (such as Polar and Suunto) include a feature that allows for data collection and reporting on R-R intervals that serve as the basis for any HRV calculations.
• Kubios HRV software
  Made available for free download by the Biosignal Analysis and Medical Imaging Group at the University of Finland, and intended originally for use by scientific investigators, Kubios HRV software allows for calculation of the most common time and frequency domain measures of HRV. Inputs can come from an ASCII file of R-R interval data or from some standard heart rate monitor data files. This software is probably the best (and cheapest) tool for athletes who might want to derive particular measures of HRV and relate them to their training. The Kubios user’s guide includes not only instruction on the software but also general information about the underpinnings of the various HRV indices.
• Physionet software
  Another option for free, open-source software comes in the form of an HRV Toolkit from the Division of Interdisciplinary Medicine and Biotechnology at Beth Israel Hospital/Harvard Medical School. These tools do not have a graphical user interface like Kubios, but do allow for calculation of many of the relevant HRV indices and graphical representation of the results.

Thoughts and Recommendations
HRV technology might well be most useful for dedicated amateur and elite endurance athletes who are looking for additional ways to monitor their training, make day-to-day adjustments to their training patterns, and avoid the negative adaptations of overreaching or overtraining. But from what we know from the rather limited studies of elite endurance athletes, HRV may not have the same, predictable relationships to a training cycle that have been observed in less-trained recreational athletes and non-athletes.

In thinking about the hardware and software tools that are currently available, the Omegawave, Bioforce, and ithlete systems might be best suited for athletes who want to use HRV monitoring for the “short term” application I described above. A Kubios-based approach might be more suitable for athletes who want to use HRV monitoring during and through various training blocks. There seems to be a real opportunity for the heart rate manufacturers and the training data analysis/repository vendors (such as TrainingPeaks) to offer some easy-to-use, mathematically transparent tools for everyday athletes.

Realize that none of this is particularly simple, at least not yet. The serious endurance athlete who wants to make use of HRV monitoring might do well to use a Kubios-based approach to track some indices for a season and to simply gain familiarity with the process. In so doing, you’d become aware of how various HRV indices related specifically to each phase of your training. You’d also become aware of both positive and negative trends in that regard. From there, you would be in a position to see how best to make use of HRV in conjunction with other markers like fatigue, performance, resting heart rate, exercise heart rate, and heart rate recovery.

There’s no doubt in my mind that the use of HRV technology will become more widespread in the endurance sports, particularly as we learn more about the real-world experiences of well-trained recreational athletes.