Bonjour tout le monde!
As my second week in Paris comes to a close, I can’t help but reflect on my time in Paris thus far. Have I accomplished what I’ve wanted to accomplish? Have I met my goals?
One major goal that I set out to fulfill during my time in Paris was to keep running. But before I delve into that, let me give you a little background on my relationship with running.
I never used to enjoy running. In fact, I strongly disliked running. My parents have always been big runners and have run marathons, done triathlons, Tough Mudder-type events, and many others. I could never understand why they would put themselves through the grueling process of burning up your lungs and muscles until you just couldn’t do it anymore. Why subject your body to that much pain? All throughout middle school and high school, the only running I did was on the soccer field or on the volleyball court. But that all changed this past semester.
I can’t tell you for sure what it was that changed my mind about running. To be honest, I think it might’ve been that I wanted to get in shape and I knew running would get me there. So I started running. Every other day, every few days… whenever I found time in my busy Emory schedule to run, I ran. And it got easier each time. I didn’t feel as fatigued when I ran, and the thought of running didn’t incur feelings of immense hatred anymore. I actually started to enjoy it… even look forward to it! You’re now reading the blog post of a girl who is signed up to run a half marathon in the fall, and I couldn’t be more excited about training for it.
While I haven’t had much time to run in Paris between classes, excursions, and exploring, I’ve tried to fit it into my schedule as much as I can, even if it’s just a short, 2 mile run. The first time I went for a run in Paris, I immediately felt better and had an immediate rush of familiar excitement. As I set off to run in one of my favorite places in Paris, the Touileries garden, pounding along to the beat of “‘Till I Collapse” by Eminem, I finally identified the feeling. It was an all-natural, all-encompassing high.
Beginning my run in the Touileries (photographed by Joy Lee)
As I entered the park and continued along the path, feeling great, I wondered what caused this high, and how it affected my running performance.
So I came back to my room later that day and did a little bit of research. I found a study from 2008 that described the phenomenon I was experiencing, called “the runner’s high”. This study by Boecker et al. (2008) looked at ten athletes at two time intervals: one after 2 hours of endurance running and one during a rest period. The researchers looked at whether particular opioid receptors (molecules of tissue that bind substances called endorphins that give us a boost when we run) get depleted when we run long distances, and they indeed found that certain areas of the brain do in fact have reduced opioid receptor availability in subjects during endurance running as compared to when subjects were resting!
Reduction in opioid receptor availability in certain areas of the brain after long distance running compared to when resting
So basically, when we run long distances, we do in fact feel an all-natural “high”, in addition to having pain-relieving symptoms — even though it often feels like we’re about to die when we’ve run for too long (Boecker et al., 2008).
This analgesic effect got me thinking though: what about when we’re extremely fatigued? We don’t seem to feel this pain-killing effect anymore: in fact, the pain is almost unbearable when we feel like we’ve reached our limit. The concept of limits reminded me of a Radiolab podcast that I had listened to while taking Human Physiology with Dr. Cafferty, fall semester 2014. In the beginning of the podcast, Jad Abumrad and Robert Krulwich (the hosts of Radiolab) introduce Julie Moss, who discusses her first Ironman experience. If you watch her running toward the finish line on YouTube, you can see how the fatigue after swimming 2.4 miles, biking 112 miles, and finally a marathon (26.2 miles) truly catches up to her.
Krulwich and Abumrad then go on to introduce what is known as the central governor theory, along with the help of physiologist Dr. David Jones. This theory describes how fatigue may in fact not be a result of muscles running out of energy: in fact, it may be more mental than we think. When we’re running low on energy, this central governor signals triggers of pain to try to get us to rest. Scientists are finding that this governor circuit is conservative, keeping a reservoir of energy readily available in case of an emergency. While some scientists argue that fatigue is one of the greatest imperfections of the body, Noakes (2012) references an Italian physiologist A. Mosso who says that fatigue may in fact be one of of our most marvelous perfections. As Krulwich jokes in the Radiolab podcast, perhaps fatigue is our body’s “almost out of gas” message, telling us we’re running out of energy when we still have a 1/4 of a tank left.
As I continue to train and eventually complete the half marathon in the fall, I know I’ll be thinking about my central governor and hoping for that endorphin boost; especially as I (hopefully) run toward that finish line, trying to avoid pulling a Julie Moss, running to the melody of Chariots of Fire.
Selfie of me while running in Montsouris park!
Until next time,
Meg
References:
Abumrad J, Krulwich R. Limits of the Body. RadioLab. http://www.radiolab.org/story/91710-limits-of-the-body/
Boecker H, Sprenger T, Spilker, M, Henriksen G, Koppenhoefer M, Wagner, KJ, Valet M, Berthele A, Tolle T (2008). The Runner’s High: Opioidergic Mechanisms in the Human Brain. Cerebral Cortex 18: 2523-2531.
Noakes T (2012). Fatigue is a Brain-Derived Emotion that Regulates the Exercise Behavior to Ensure the Protection of Whole Body Homeostasis. Front Physiol. 3:82.