RTP Interview #4 Marco Altini

At RTP we are delighted to be able to interview Marco Altini, founder and creator of the platform and the HRV4Training app (www.hrv4training.com). From this platform, Marco achieves what we truly seek for all our content and provides the evidence and quality that approximates the science to its use in our daily practice. Throughout this interview, we will talk about what HRV is, what information it gives us, how we can measure it through the app and how we can use this data in our own situation.

RTP: First of all, Marco, thank you for agreeing to this interview with us. I also use the HRV4Training app, both for myself and with my players so, in this sense, I also want to thank you for providing it for fitness coaches.

Marco: Thank you Jorge, great to hear, and really appreciate your invite

RTP: To get ourselves into context, what is HRV (as a physiological parameter) and what information does it give us?

Marco: HRV refers to the variability between heartbeats and is a proxy of physiological stress. When we face a stressor, the autonomic nervous system modulates heart rhythm, in a way that is measurable with HRV analysis. This means that we can quantify indirectly the impact of the stressor by analyzing HRV. Typically, a lower HRV with respect to our historical values, highlights higher stress. This is a sign that we are not responding well to training and lifestyle stressors.

RTP: Your HRV4Training app has been created to monitor this parameter. It is an application that is really easy to use, but which has great scientific value, as it has even independently validated. What can you explain to us about its use and applicability for athletes and coaches?

Marco: With HRV4Training, we wanted to create an accurate but cost effective tool, so that more people could access this technology, and analyze their own physiological responses to the different stressors we face. In sports settings, measuring HRV daily when we wake up, first thing in the morning, can give us an indication of the overall physiological stress level on the body, which can be used to implement useful changes. For example, if our HRV is suppressed with respect to our historical data, this is a sign of a poor response either to training or other stressors (e.g. travel, work or family related stressors, sickness, etc.). In this case, research showed that reducing the intensity of the training stimulus can be beneficial for long term performance.

RTP: On a personal level, I would like to highlight an important advantage of the app. A great relationship between time (one minute), necessary material (a mobile device) and the quality and validity of the information obtained. I believe that this makes it an interesting investment for athletes and coaches at any level that are looking to add quality to their training process.

Marco: Thank you Jorge, this is exactly what we want to be able to provide to recreational and professional athletes worldwide. If the tool is not easy to use, accurate and cost effective, it becomes difficult to maintain the habit of collecting this data on a daily basis, and this is a parameter that becomes useful only if we collect data daily for a long time, in relation to the various stressors we face. We should not necessarily see HRV itself as something to improve over time, but by making small changes to our lifestyle and training based on HRV, what we end up improving and optimizing, is our health and performance. HRV is a tool that allows us to close the loop between what we do (the stressors we apply for example, training or other) and our body’s response to such stressors. 

RTP: The app bases its interpretation of the data on each person’s “normal” values, so the analysis is more individual and is not based on absolute reference values.  Will keeping the HRV within the “normal” values help us to adapt to the training stimulus?

Marco: Exactly. We start analysing an user’s normal values after the first 4 days of data collection, but over time, we end up always using the past 60 days of data to make sure we have a good picture of what a person’s historical data looks like. This is key because HRV is highly individual, and differences between people are mostly linked to genetics. Knowing our absolute value in HRV, does not really tell us much, but monitoring changes over time with respect to our normal is key to try to keep stressors in balance. As you say, keeping our HRV within our normal range is typically an ideal response, as it highlights that we are responding well to training and lifestyle stressors, and we are able to bounce back quickly from such stressors. Frequent suppressions or unstable data, often outside of our normal range, are typically associated to poor responses, or a mismatch between the applied stimulus and our capacity to assimilate the stimulus.

RTP: What information can a change in the HRV give us, both at an acute level (day-to-day) and in the medium term?

Marco: Acutely, we have some stressors that are quite easily captured, as they have a strong impact on our physiology for 24-48 hours. These are for example high intensity training, the menstrual cycle (with a suppression in the luteal phase), alcohol intake, sickness and travel. In the long term, things are more complicated to analyze, but also more interesting. For example, while we know that training causes a suppression in HRV, when we are in a high training load block, we typically want to see a stable or even increased HRV, this would be a sign of positive response and good adaptation.

RTP: Its main use is by endurance athletes, but might we find it useful to monitor and control HRV in team sports despite their performance not being as directly related to the athlete’s physiological status? How can this help us?

Marco: Certainly. In team sports, the data is probably less strongly associated with performance, as other skills have a larger impact. However, as HRV is a global marker of stress, not something training-specific, it can become very important to keep track of how athletes are doing in relation to for example frequent games and travel, aspects that are in fact less relevant for endurance sports. Additionally, in specific phases of the season, for example during pre-season, HRV can help us identifying how individual players are dealing with the increased load, and potentially make adjustments in case of suboptimal responses.

RTP: The ultimate aim of monitoring the variables that we can control is to be able to make decisions. If we put the monitoring data obtained and the HRV control into context with other variables that we can record (depending on each context/sport), could this help us to make decisions that modify the training process, through adapting the planned training (session, microcycle…) if the values as a whole indicate a clear trend?

Marco: In my view, we should always spend first a couple of weeks, or ideally months, just looking at the data and contextualizing individual responses. This can help us identifying patterns, and seeing how different athletes respond to specific phases of the season, training, games, travel, or other unplanned issues (e.g. sickness). Once we have collected data for a few weeks and are seeing some useful trends, it can be a good time to start implementing some changes, as of course we want to use the data for decision making. Typically, modulating training intensity or trying to better manage other external stressors when HRV is suppressed, is a useful approach to training individualization and stress management.

RTP: If maintaining the HRV at normal values helps us to better assimilate the training stimulus, could a practice such as ‘deep breath’ or through another of your app (HRV Biofeedback) support the parasympathetic stimulus and, therefore, place the body in a better position to adapt to such a stimulus?  

Marco: This is a fascinating question for me, but I do not think we have an answer yet. Literature is quite inconclusive on the impact of deep breathing practice on athletic performance and recovery, but I think this can be an interesting area to explore, especially with some players (traits like being more or less anxious could also play a role on the effectiveness). We developed HRV4Biofeedback with the idea that this way, we could experiment more with deep breathing protocol, that potentially can train or activate the parasympathetic branch of the nervous system, the one in charge of rest and recovery, and this might have an impact on our ability to take additional stressors. The jury is still out

RTP: To finish now, Marco, are there any great myths about the monitoring and control of HRV that you would like to clarify and that may help us to better understand this process?

Marco: There are probably way too many. One important aspect that I’d like to highlight is that HRV is a useful marker of stress, and probably the easiest to measure these days (measuring other stress pathways, such as hormonal responses, is not feasible on a daily basis), but HRV is only part of the picture. First, we need to be able to contextualize the data, for example in relation to external load (training), as well as subjective metrics (how the athlete feels, sleeps, etc.). There are also aspects that are key to training that are not captured by HRV, the most important one is muscle soreness. All of this tells us one simple thing: HRV is not a replacement for other variables but needs to be used together with subjective feel and training load, so that we have a full picture on an athlete’s response to different stressors and can individualize training accordingly.

RTP: Marco, thank you so much for answering our questions and for your support to all of us working in the world of sports training and health.

Marco: Thank you for having me and all the best for your work