This is the FOURTH in a series of entries on my blog about my bout with overtraining. … Part IV is about the “self-education” I’ve gone through to better undertand my body and its limits. It’s somewhat frustrating that the medical community understands very little about this syndrome.
Back to the blog after a much-need vacation: a road trip in Norway, a visit to Germany for an Outdoor Show, gardening at home, and daily ‘training sessions’ of my parasympathetic nervous system …
In trying to educate myself about overtraining, I’ve listened to a lot of podcasts (local health care providers don’t have a clue how to approach my problem). Three things seem to pop up again and again in the discussion about the optimal endurance training regime:
- Imbalance in the autonomic nervous system (sympathetic vs parasympathetic)
- Heart Rate Variation – a measurement of the “time ” between heart beats
- A distinction between health and fitness.
So I’m going to try and explain why the parasympathetic nervous system matters to adrenaline junkies, how we can measure success in “rest and recovery”, and why being fit is not the same as being healthy (I’ll be talking about these topics with Markus Torgeby in Trillevalen (7th August at 17.00). More info (in Swedish) coming soon to the AXA fjällmaraton page here.
But first some summer pictures …
Running in Norway …
… and resting in Norway
Giving a multisport presentation at the Thule Booth at the Outdoor trade show in Friedrichshafen, Germany.
The garden is coming along nicely … if slowly
The Autonomic Nervous System
Understanding overtraining begins with understanding the body’s ability to “automatically deliver” to keep us alive and to keep us thriving as humans. This delivery system is the Body’s Central Nervous System, which basically coordinates all activity and every organ in the body …
But what’s interesting is the portion called the Autonomic Nervous System, which controls all the body’s daily functions without asking you when or how you need it. It’s pretty fascinating and it’s divided into two systems:
- Sympathetic nervous system (“fight of flight”) is ready to kick the body into gear when we need energy, like when we’re starting up a training session (physical stress) or we’re worried about a work deadline (mental stress). I’ve had plenty of both in the last few years.
- Parasympathetic nervous system (“rest and digest”) is the counter balance, as it slows the body down in order to ensure proper rest and recovery. For example, it helps the heart rate come back to normal after a training session or after delivering a stressful presentation at work.
Two things stick out from my podcast research:
- The parasympathetic system seems to follow a “use it or lose” approach, i.e., it can only provide the “rest and digest” service if we let it (!) through deliberate rest, long out-breaths, lying down or just “turning off.” If we don’t do this, the system feels un-wanted and stops working effectively.
- But the most important thing seems to be that the sympathetic and parasympathetic systems are in balance, i.e., both are active and ready to go at the appropriate time. Like I said, they take care of themselves … at least until you (or I) get in the way.
An over-trained athlete has “gotten in the way” by (1) calling too often upon the “fast mobilizing” services of the sympathetic system and (2) failing to engage the parasympathetic system which, like an old car, becomes “rusty and un-reliable.” Historically, these fast-mobilizing services have allowed us to survive in the Savannah of Africa when being chased by a lion, but the problem is that we (as a modern society) are calling upon these services too often for things that don’t threaten our survival (e.g., mental stress and gratuitous endurance training).
So this explains my focus on daily parasympathetic ‘training sessions’: i.e., at least 30 minutes a day where I lay down and train the “rest and digest” service (just like I used to train my cardiovascular system with endurance workouts).
So how do I know when/if I re-establish my “sympathetic-parasympathetic” balance? There is no magic answer but it turns out that a new measurement is starting to show some promise ….
Heart Rate Variation (HRV)
If you read my blog you know how much I rely on a heart rate monitor to measure my heart rate during training (beats per minute). But it can also be used by endurance athletes to measure heart rate variation (HRV), a measure of the time between each heartbeat. Let me explain …
Imagine you have a resting heart rate of 60 beats per minute. Then, in theory, there is exactly one second between each heartbeat. But is that healthy?
The answer is no. It’s actually healthier to have variation in the length of the ‘pause’ between each beat. A healthy person with a resting heart rate of 60 might have less than a second between some beats and more than a second between other beats during a typical one-minute sampling of the pulse (the variation naturally decreases as the heart rate increases, as in training). A high HRV is an indication of a healthy balance between the sympathetic and parasympathetic nervous system, while a monotonic (constant) rhythm indicates an imbalance between the two systems.
Check out this interesting graph from a white paper developed by Suunto in updating their heart rate monitors to include HRV measurement. The HRV is measured using RR intervals, which measures the time between each heartbeat in milliseconds (ms). You can see that the RR interval varies from 860 to 1040 ms in this relatively healthy individual. But what’s more interesting is that the parasympathetic (“rest and digest”) is more active during the out-breath phase, which is proof that deliberate resting/mediation actually helps to train this system (and no, it doesn’t count to be lying on the couch playing with your iPhone).
From “Stress and Recovery Analysis Method Based on 24-hour Heart Rate Variability” Published: 16/09/2014, updated: 04/11/2014 by FirstBeat Technologies LTD
How can we measure HRV? Thanks to the new generation of heart rate monitors (chest straps) based on Bluetooth technology and a host of new apps for smart phones, we can measure HRV easily and inexpensively. One example is the Sweetwater app which costs $5 (See also podcast #6 from Primal Endurance for a really good explanation). Alternatively, if you have the Ambit3 with the newest update (Spring 2015), this measurement is now included (Read more here)
But how do we know if our variation is healthy? This is harder to answer, as there is no rule of thumb that applies to all individuals. Some have a naturally high variation, while others have a naturally low variation. But what we can do is take a baseline measurement for our own body and then see how that varies during a 24 hr period, a week, a month, etc. If the variation starts to decline, we can interpret that as a relatively robust and objective measure of overtraining – or at least a tendency toward overtraining.
Health vs Fitness
Endurance athletes are no doubt fit: our bodies can run/bike/paddle long distances. So that means we are obviously healthy, right? Not so fast … it turns out that strong and lean muscles are not synonymous with health.
First, what is fitness? I might say it’s being able to complete (and perform well) in long and challenging endurance events. But this says nothing about a person’s wellness or the state of the body after completing the event.
Health is a wider concept; it’s about functioning day to day without disease or injury. It’s usually focused more on long term sustainability and considers what you eat, how often you move, and how well you can handle and recover from typical and normal daily stress.
I’m a perfect example of a very fit person that has become un-healthy. During my period of over-training I’ve slept poorly, felt exhausted, and frequently wake up sweating at night. Further, I have a hard time relaxing as my sympathetic nervous system is stuck in overdrive.
The “health vs fitness” theme is becoming increasingly popular on podcasts aimed at (fit and competitive!) endurance athletes. A good example is Mark Scission’s Primal Endurance podcast. Together with his co-host Brad Kearns, Mark is writing a book on this topic coming out in the fall of 2015. Mark is a former elite triathlete, so when he speaks, I listen. He’s credible.
I live for hard three day stage races (6+ hrs per day) in hot and humid China … but perhaps not so healthy?
While the “fitness vs health” paradox is less of a problem for a recreation athlete, it’s a sobering thought for an athlete like myself that wishes to perform on an elite level. One interpretation is that elite racing is simply unhealthy and I should drop it, but that might be painting an overly “black and white” picture. Another interpretation is this: as a high-performance endurance athlete, I compromise my health over the short-term to pursue my passion, which is not only fulfilling but also helps to define who I am and builds my individual character, which is important outside of my sporting life. But to ensure my passion is more sustainable I’m seeing the importance of “periodizing” my racing schedule, so that I balance a relatively unhealthy “fit” period with a relatively healthier rest and recovery period.
But, of course, that assumes that I recover and get a second chance at this endurance gig.
PS. Here are some good podcasts if you’re interested …
Jonas Colting (Swedish, see the one on overtraining and stress)