Healthy Brain, Happy Life (24 page)

TELLIN’ IT LIKE IT IS

I typically get one of two reactions when I tell people that I’m a neuroscientist who studies the effects of exercise on brain function. The first is “That is
so cool
—I want to know all the results of your studies!” The second is “Of course we know that exercise improves brain function! Isn’t that old news?”

I think these two responses reflect the effects of the popular press on this exciting field right now. On the one hand, there are popular articles being published almost every day about the positive effects of exercise on brain function. These articles are wonderful in the sense that they keep the general public up to date on the latest findings, but they have a tendency to make strong conclusions based on the publication of a single study, giving the false impression that we know much more than we do. So I can understand the people who have the impression that most everything is already known.

The reality is quite a different story. It’s true that there are more and more neuroscientists focused on examining the effects of exercise on brain function in both animals and humans, but there are still many big and exciting questions left to address. For example, the studies thus far in animals have focused strongly on the effects of exercise on the hippocampus and on identifying the neurotransmitters and growth factors that change with exercise. There is a rich literature there, but an exciting direction will be examining the brain effects of exercise outside of the hippocampus. For example, the most common finding in humans is the effects of exercise on prefrontal function. Very little is known about the effects of exercise in the prefrontal cortex in rodents. Similarly, there is exciting literature on the positive effects of exercise in the easing of symptoms in Parkinson’s disease. These findings suggest a strong effect of exercise on the striatum, the primary area of the brain damaged in Parkinson’s. Very few studies have examined how exercise affects the striatum in normal animals. But perhaps one of the biggest unanswered questions that can be addressed by studies in animals is understanding the precise pathways, molecules, and mechanisms for how exercise is triggering any change in the brain. In other words, we know that if you let a rat exercise, you can see changes in BDNF, endorphin, dopamine, acetylcholine levels, and neurogenesis, but we don’t know exactly how exercising is stimulating all these changes. It could be myriad different factors that do the trick, and different factors could be responsible for the wide range of observed brain changes. It could be the increased heart or respiration rate or the change in blood flow, muscle activity, and/or body temperature that stimulates the brain. It’s a complex problem and many basic questions remain unanswered. One recent study claims to have identified a factor secreted by the muscles that can pass into the brain and stimulate the release of BDNF. This is an exciting new report and will need to be replicated and confirmed by other studies.

In people, a mountain of questions remains; many of them have been raised by animal studies and are waiting to be confirmed with randomized controlled studies in humans. The preliminary studies have whet our appetite and told us there is something there, but I want to know if all the striking changes reported in the rodent brain can be seen in the human brain. In a nutshell, it’s the prescriptive piece that is missing from the humans studies and that forms the core of the research program in my lab. Here are some of the key unanswered questions about the effects of exercise in humans that fascinate me:

•   How much (or little) exercise do I need to see improvements in memory or attention?
Answer:
We know that short-term exercise for thirty to sixty minutes can improve attention, but we don’t yet know how long the improvement lasts. After an increase in exercise over eight to twelve weeks, we see an improvement in attention and sometimes memory.

•  How long do brain enhancements last in humans after exercise?
Answer:
We don’t know in the case of acute exercise or long-term exercise.

•  Which brain function improves with the least amount of exercise?
Answer:
We don’t know.

•  What kinds of exercise are most effective?
Answer:
There is evidence that aerobic exercise is more effective than stretching or resistance training, but we don’t yet have a good idea of which kinds of aerobic exercise might be best or what level of cardiac output might be best to enhance cognition.

•  Does yoga help my brain?
Answer:
There are a few studies on the effects of yoga on the brain mainly focusing on how the meditative aspects play into brain function. But there are too few studies of this kind to make firm conclusions.

•  Can I take a pill and get the same effects as exercise?
Answer:
No. While many have attempted to create this magic bullet, there are no pills available that can reproduce the widespread effects of exercise on brain function.

•  What time of day is best to exercise?
Answer:
The first answer is any time of the day that lets you exercise regularly! The scientific jury is still out on definitively determining the best time of day to exercise. My personal preference is to exercise first thing in the morning. This gets the positive hormones, neurotransmitters, growth factors, and endorphins flowing, preparing me for the workday. While this may be true, it still has not been definitely proven which time of day is more beneficial for cognitive performance. It may also be that no matter what time the workout, the long-term changes in brain chemistry and function may emerge irrespective of the time of day of your regular workouts. In the absence of definitive evidence, I choose the theoretical best answer for preparing the brain for a day of work: an early morning aerobic workout.

All the exciting research findings in rodents showing striking brain changes conferred by exercise make exercise one of the most exciting potential therapies around. It’s free and available to all. It has the potential to improve brain function in healthy brains, young brains, old brains, and diseased brains alike. It can help students young and old learn better in school. And it makes you happy as it improves various cognitive functions in your brain. This is why I’m excited to devote the next phase of my career to this area.

THE CLASS THAT REFLECTED MY LIFE

My “Can Exercise Change Your Brain?” class, a brand-new kind of hybrid course, represented the brand-new kind of challenges I was taking on in my own life. Not satisfied with continuing on my single-minded academic science track focused on the neurobiology of memory, now that I had tenure, I was starting to explore other areas of scientific interest to me irrespective of whether I had studied them before or not. I think I was just on a roll that started with the change in diet and exercise that I made in my life and how it had changed the way I felt in my body and the way I moved around in the world. It turns out that those changes also changed the way I saw myself. I started to see myself as strong, powerful (just like the affirmations that I was doling out in class), and able to make any change I could come up with in my life. And I was getting a little hint of that inspiration every single time I went to exercise class. In every class, in addition to the surge of all those good brain chemicals, I was reminded that I could push myself exactly as hard as I wanted to and feel the benefits in terms of my own strength and endurance. And this transferred to other exercise classes I was taking—from kickboxing to cardio sculpt classes to spin. And though these other classes didn’t incorporate the same kind of explicit intention practice, my own awareness and attunement to my emotional experience during those workouts was just as elevated as during intenSati. With all of this mental and emotional energy in the form of heightened motivation, I felt I could move mountains.

This inspiration not only affected the courses I developed but started affecting other aspects of my life as well. For example, while I started out developing the “Can Exercise Change Your Brain?” class as a kind of science hobby, there was a clear moment while teaching that first semester when I realized the topic was more than just a hobby for me. It happened when Omar, one of the students in that first class, came to talk to me about doing some independent research on exercise in my lab. Omar was a varsity athlete. In fact he was the starting point guard on NYU’s men’s varsity basketball team and no stranger to long, hard workouts. He was quiet in class but had a deep interest in the brain effects of exercise because of the time he spent in the gym practicing. Soon after class started he came to my lab asking about whether he could do a research study under my guidance in the lab. While the study we were doing as part of the class focused on the effects of long-term exercise (increased exercise for three months), Omar was interested in asking if you could see evidence of significant improvements in cognitive functions after just one hour of aerobic exercise. It was a great question and I happily agreed to have him join the lab to do this project. But I actually had no other research in my lab at the time studying exercise. His request made me realize I did want my lab to start to study this question in a serious way. This was the moment when I left exercise behind as a science hobby and declared it a major theme of my research lab. I was not an expert in this area but was more than eager to do the work to become one.

This newfound spirit of exploration even affected my dating. I had enough of the NYC matchmakers and decided to see what I would find online. They say that you attract the kind of person that you are yourself, and one day as I was browsing the profiles of an online dating service I had signed up for, I stumbled on one that immediately caught my attention. It had no picture, which usually meant an immediate pass for me, but the profile itself intrigued me. He was a professional musician, never married, living in New York, and had played with some of the best orchestras in the city. Hmmm. Ever since François, I’ve had a soft spot in my heart for musicians. Maybe this one was worth another look. For this particular online dating website you had to answer more questions to get to the next level, and when I did that, I did see a picture and I thought he looked nice, though somewhat intense. But he was a professional musician working in New York City, what did I expect?

THE MATCHMAKER FROM HELL

I don’t have anything against matchmakers. The two I worked with provided me with some reasonable if not completely stellar dates and one serous relationship (Art). But my last encounter with a matchmaker put me off them for the foreseeable future. I went to an evening spa event with my dear friend Cheryl Conrad, a neuroscientist from Arizona, to hear what the guest speaker, a matchmaker, had to say. The matchmaker was very thin, and I couldn’t help noticing that she didn’t smile very much and didn’t look all that happy to be there. She talked for fifteen or twenty minutes about her philosophy in matchmaking and the mechanics of how it all worked. It got interesting only after she finished her presentation and said she would take questions. An elegant-looking woman wearing high black boots and what looked like a Diane von Furstenberg wrap dress raised her hand, and said, “I have a friend who has a problem because she is always intimidating the men she dates. What do you suggest?”

Without skipping a beat the matchmaker said, “Well, the first thing I would do is stop wearing those hooker boots.” Apparently, the matchmaker was referring to the high black boots that went a little above the knee that the woman was wearing. I would never have thought to compare them to the boots Julia Roberts wore in
Pretty Woman
, but that’s me.

The room went deathly silent. I think everyone was holding their breath to see who would say what next. Fistfight? Screaming? Hair pulling? Anything could happen.

The woman calmly replied, “I said it was a friend.”

After a split second, in which I do believe the matchmaker realized just how insulting she’d been, she said, “Well, intimidation is common in dating—especially in New York.” I can’t remember the rest of what she said because I was just so shocked at how rude she was and wanted to get away from there as fast as possible!

No, there were going to be no more matchmakers for me, and definitely not Miss Hooker Boots. Onward and upward!