Tag Archives: running

Sugar, Parisian Sights, and Group Runs are Nice

Bonjour family and friends,

When I first arrived in Paris two weeks ago, I was excited to find so many active Parisians running and biking everywhere! Walking around the Cité Universitaire residential campus, I am often startled by a breathless “Pardon!” (Pardon me!) as a runner passes by on my left. Also, more than 20,000 bikes are available for rent in Paris through Vélib’ for €1.70 per day (visit http://en.velib.paris.fr/How-it-works/Bikes). My Paris bucket list definitely includes trading my metro pass for a bike for at least one day in the upcoming three weeks.


Vélib’ public bicycle sharing system

One of my professors, Dr. Jacob, and our TA, Rachel, lead group runs in parks around Paris. I ran my first half marathon this past March in Atlanta and wanted to continue running and exercising while in Paris. Running is a great opportunity for sightseeing and exploring beautiful, natural spaces such as parks, gardens, and riverbanks.

park run

Rachel and I spreading our wings toward the birdhouse carvings in the tree!

Running also helps work up a healthy appetite…Lucky for me, there’s a boulangerie (bakery) on the corner of each street!

During the hour-long lunch break between my two neuroscience courses, I usually orient myself towards a boulangerie for lunch. Nearly every boulangerie’s Formule Dejeneur (or Lunch Formula) includes a sandwich, drink, and dessert that’s almost too pretty to eat. With so many boulangeries and crêpe stands as far as the eye can see, Paris must be every sugar addict’s heaven on earth. However, such easy access to desserts makes me wonder about the current diabetes rate in France. Also, I wonder in what way physical exercise, such as running and biking, can affect a diabetes patient’s brain. After some online research, I found a few neuroscience explanations to satisfy my curiosities (for now).

Formule Dejeuner

Sample lunch formula


Tarte au Citron

Tarte au Citron (Lemon Tart) – Is your mouth watering yet?

First of all, diabetes is a disease in which high blood sugar levels exist over a long period of time. I personally know a few individuals who are pre-diabetic and have to carefully monitor the sugars they consume. Drawing from a research study published today (6/8/2015) in The Lancet, a British medical journal, diabetes occurrence increased 45% from 1990 to 2013 (Global Burden of Disease Study 2013 Collaborators, 2015). In France, 7.2% of adults (20-79 years old) suffer from diabetes. This percentage represented about 3,241,300 diabetes cases last year in 2014 (visit https://www.idf.org/membership/eur/france).

Diabetes, specifically diabetes mellitus, directly relates to neuroscience because this disease decreases brain function and leads to neurodegenerative diseases (Yi, 2015). In a research study hot off the press (5/22/2015), Nunes de Sena et al. investigated the effect of treadmill training on the brain function of diabetic rats. They divided sixty rats into four groups, with exactly fifteen rats in each group.

  • Group one included non-trained, healthy rats.
  • Group two included trained, healthy rats.
  • Group three included non-trained, diabetic rats.
  • Group four included trained, diabetic rats.

Based on this experimental break down, half of the rats received a chemical injection (streptozotocin) that led to diabetes over the course of thirty days and symptoms of hyperglycemia and body weight loss throughout the experiment. After thirty days, the exercise (“trained”) groups underwent five weeks of running training on a treadmill apparatus.

rat on treadmill

Could you imagine seeing this runner training at the gym?

On the day after the last training session, all of the rats participated in a short-term memory test, known as the Novel Object-Recognition Test (NOR). Rats were placed at the center of an open field apparatus (a.k.a. box) and given three minutes to explore their new environment. (This acclimatization period reminds me of the first few days after our arrival in Paris. We also landed in a new environment that we needed to adjust to before beginning coursework.) After the initial three-minute exploration time interval, testing included two five-minute trials. In the first trial (T1), the researchers placed two different objects inside the testing box. In the second trial (T2) one hour later, a new object replaced one of the objects from the first trial. The objects were as different as they could be! They differed in shape, surface, color, contrast, and texture. The researchers recorded the amount of time the rats spent exploring the new object and divided by the amount of time the rats spent exploring both objects, to check for any object preference. In terms of results, both of the exercise groups exhibited a stronger preference for the novel object. Thus, the researchers concluded that treadmill running improved short-term memory performance in both healthy and diabetic rats. I am not entirely convinced, however, based on results from one memory task. In order to establish a stronger connection between running and short-term memory, I think multiple, diverse memory tasks should be carried out. Overall, this paper is significant due to a major strength in the design of the research study: for the first time, researchers used diabetic rats to show that exercise improves performance in a non-spatial memory task. I am highly interested in reading future studies regarding the effects of exercise on other components of brain function in diabetic rats! Hopefully, such studies will contribute to more naturopathic treatments for pre-diabetic and diabetic patients.

With so many picturesque gardens, parks, and the Seine River, Paris provides countless opportunities for running. Even if you have normal blood sugar levels, what are you waiting for? Explore as you run!

À bientôt,



Bill F, Foundation MG (2015) Articles Global, regional, and national incidence, prevalence, and years lived with disability for 301 acute and chronic diseases and injuries in 188 countries, 1990 – 2013 : a systematic analysis for the Global Burden of Disease Study 2013. 6736:1990–2013.

De Senna PN, Xavier LL, Bagatini PB, Saur L, Galland F, Zanotto C, Bernardi C, Nardin P, Gonçalves CA, Achaval M (2015) Physical training improves non-spatial memory, locomotor skills and the blood brain barrier in diabetic rats. Brain Res: 1–8 Available at: http://www.ncbi.nlm.nih.gov/pubmed/26032744 [Accessed June 7, 2015].

Yi SS (2015) Effects of exercise on brain functions in diabetic animal models. World J Diabetes 6:583–597 Available at: http://www.ncbi.nlm.nih.gov/pubmed/25987956 [Accessed May 21, 2015].

All images were obtained through a Google image search, besides the image of Rachel and I in the park and the image of the Tarte au Citron.


An All-Natural High: Running through Paris

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!

Screen Shot 2015-06-07 at 7.26.04 PM

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,



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.