Over the next several posts I’d like to share my thoughts on ways that you can increase your HRV to improve your health, fitness and responsiveness to training. I will tie in some research with anecdotal experience and encourage you to keep in mind that some of this may be a bit theoretical at times. These thoughts are based on my current knowledge level and experience with HRV as well as discussions I’ve had with other like minded individuals (many of which are much more experienced than I).
I’ve spent a lot of time lately reading about the relationship between inflammation and HRV and therefore this will be the focus of today’s discussion. I highly recommend checking out this article where Dr. Miller presents and summarizes some of the research pertaining to nervous system regulation of inflammation and HRV. I don’t yet fully grasp this relationship as the physiology of inflammation can get pretty technical to say the least, but I would still like to offer some thoughts. Before I get into further detail about anything I’ll go over some preliminaries.
What is inflammation?
Inflammation is the protective or destructive response of body tissues to irritation or injury in attempt to maintain tissue homeostasis. Inflammation may be acute or chronic. The hallmark signs of inflammation are; redness, heat, swelling, pain and is often accompanied by loss of function. Too much inflammation or too little inflammation can be indicative of, or lead to a variety of diseases.
At the most basic level inflammation is a sympathetic response. This isn’t exactly black and white however as I’ve come across some research that shows how the SNS can actually play a small role in reducing inflammation in certain organs under certain conditions (Straub et al, 2006). However, for the purpose of this discussion I’ll generalize the SNS as being predominantly involved in inflammatory responses.
Parasympathetic activity on the other hand, modulates inflammation by inhibiting the secretions of pro-inflammatory cytokines (Mravec, 2011). Inflammation is not just caused from physical stress (training, injury, etc) but can also be brought on by; ingesting certain foods, excessive alcohol intake, smoking and exposure to pollution and certain chemicals. It appears that even psychological stress can cause inflammation (Steptoe et al, 2001).
It should be obvious that inflammation is pretty important to one’s survival. Inflammation is a major part of the healing process. For example, inflammation is necessary for hypertrophy (muscle growth) as it participates in protein breakdown, removal of damaged muscle fibers and production of prostaglandins (Pedersen & Hoffman-Goetz, 2000).
To effectively adapt from a stress (like training) we need to allow our body to go through the process of healing itself. In doing so, we increase our tolerance to the initial stressor. With adequate adaptation to strength training, we increase our strength (this applies to endurance, hypertrophy or any other quality you train to develop). So this explains why making sure we are sufficiently adaptable is important.
The simplest and most effective measure of your adaptability in my opinion is through heart rate variability (HRV) monitoring. In short, HRV tells you when your body can tolerate stress well (such as training) and when it can’t. It does so by providing the user with information about the balance of the autonomic nervous system. It does this by measuring the variability between your heart beats over a given period of time.
High HRV = low inflammation, good recovery, good testosterone-cortisol ratio, high tolerance to stress (good adaptability) → A green light for training.
Low HRV = an increase in inflammation (not always), insufficient recovery, reduced testosterone-cortisol ratio, low tolerance to stress (poor adaptability) → Reduction or cessation of training suggested.
It can get a little more complicated than this but for now this explanation will suffice.
Back to inflammation…
So even though I just explained why inflammation is important I’ll switch gears here and say that we are not doing ourselves any favors by contributing to further inflammation via nutritional, environmental and/or psychological factors.
Some of this is out of our control such as pollution and mental stress. It can be difficult to control what’s in the air we breathe or the chemicals we absorb from different surfaces and products. We also can’t control our car breaking down or other mentally frustrating events. However, we can control things like what we ingest (and what we don’t for that matter), how much we sleep, our fitness levels, and so forth. Maximizing these controllable variables can really enhance your adaptability by reducing or preventing unnecessary inflammation and/or promoting parasympathetic activity.
The forthcoming installments to this series will focus on ways that can potentially help raise your HRV (nutrition, aerobic work, restoration, massage, etc.).
The plan right now is for the next post to be about nutrition. I’ve enlisted the help of a friend who’s completing his PhD in Nutrition at the University of Saskatchewan to explain how certain foods contribute to inflammation and why this is something we generally want to avoid. I feel that much of the information presented in the next post will really illustrate WHY you should be more conscious about what you eat. As a former athlete and current trainer of athletes I’ve seen what it’s like to be on either side. Athletes know that they’re supposed to eat certain foods and avoid others. But they usually don’t understand why. They have a hard time understanding how what they ate on the weekend can affect their ability to get stronger or faster. We’ll discuss not just the importance of reaching appropriate macronutrients (protein, carbs, fats), but touch on which sources are likely better than others. We’ll touch upon alcohol intake as well since that’s obviously a major factor in the life of college (and let’s be honest, high school) athletes.