Miami Brain Fitness » Fitness

Exercise, Mitochondrial DNA, and Brain Fitness

rlo — Sat, 12 Mar 2011 01:54:32 +0000

One very influential theory of why our physical and mental functions decline with age holds that changes in our DNA accumulate over time so that out cells don’t work any more. Perhaps the most important part of our DNA exists in every cell in a special part called the mitochondia. Mitochondria are especially important because they are the part of the cell that helps it generate energy. DNA contains the programs that generate energy, but over time errors accumulate in the programs until eventually they don’t work very well any more. Errors in the programs that run our cells happen all the time — but when we’re younger the cells can fix themselves. As we get older, the cells don’t fix themselves as well. The result: our bodies don’t work as well as they used to. Over time, things start breaking and can’t be fixed. Eventually . . .

A recent study reported in the Proceedings of the National Academy of Science reports on a way to reduce the errors, at least in mice who are prone to an increased number of DNA errors. These mice have an increased number of errors in their DNA, and even early in life start to show signs of aging that are eerily similar to those seen in humans: hair loss, graying, low of body weight, and problems in mobility. Researchers at McMaster University in Ontario, Canada, compared mice with the increased number of errors to regular mice, and looked at what happened if some of the error-prone mice spent time exercising.

The group of the mice who had DNA errors exercised for 45 minutes on three days a week for 5 months. The researchers then compared the three groups: (1) DNA error-prone who didn’t exercise, (2) DNA error-prone who exercised, and (3) regualr mice who had normal DNA. Result: The error-prone mice who exercised looked the same as the regular mice. They weren’t just stronger, or in better shape, or able to run longer. They “lacked visible features of the accelerated aging phenotype (alopecia and graying hair) and were visually indistinguishable from age-matched … littermates” (page 4135).

Does this mean that if you start exercising regularly you can reverse aging? Probably not. But good research continues to accumulate that shows that exercise can improve cognition and keep the effects of aging to a minimum.

You can find an abstract for the article here. To read the full article, you will need a subscription to the journal.

Walking, BDNF, Hippocampal Size, and Brain Fitness

rlo — Wed, 09 Feb 2011 12:53:58 +0000

Maybe I have an obsession. Maybe I’m addicted to exercise. Maybe. But here it is, once again: Yet another study has shown that aerobic exercise is good for your brain. Not only does aerobic exercise improve cognition (at least 20 or more studies have shown that), but it can help to prevent age-related declines in the size of the hippocampus. The hippocampus is a critically important structure in the brain that is a key part of a circuit that creates new memories.It tends to get smaller with increasing age, but exercise can actually increase its size. The increase in size may be related to increased levels of brain-derived neurotrophic growth factor (BDNF), a substance in the body that promotes the growth of new brain cells.

In an article published online on January 31st in the Proceedings of the National Academy of Sciences, researchers show again that regular walking can make a difference in cognition. This study is new because the researchers also looked at the volume of the hippocampus with imaging techniques and looked at BDNF levels.

Exercise and BDNF levels may also be related to the way that antidepressants work to reduce depression, and we know that for many individuals exercise improves mood. While we think of the hippocampus most often because of its role in memory, it also has important effects in regulating emotion.

You can find the abstract here. The full article is available to subscribers only.

Cognitive Training, Gait Speed, and Brain Fitness

rlo — Mon, 13 Dec 2010 02:54:21 +0000

An article in this weeks’ Journal of Gerontology, provides some interesting information on how cognitive training can actually affect someone’s physical status. The article, titled “Effect of Cognitive Remediation on Gait in Sedentary Seniors,” reports on a small group of elders who completed 8 weeks of computer-based cognitive training. The authors found that the elders who completed cognitive training actually showed an increase in walking speed (even though that wasn’t part of the training).

This is significant for several reasons. First, it suggests that a mental activity can have positive effects on someone’s physical status. Said this way, this isn’t all that surprising — we’ve known for many years that relaxation can help to control blood pressure, and that stress management training can help to reduce the risks of heart attacks. The leap to something as basic as walking speed, however, is new.

Second, the study suggests (at least to me) that the link between mental and physical decline may work both ways. We’ve known for some time that exercise, for example, can have positive effects on cognition. This study suggests that the reverse may be true: that cognition can have a positive effect on physical status.

One more reason for all of us to continue to be both mentally and physically active.

Reference:

Verghese J, et al.(2010). Effect of cognitive remediation on gait in sedentary seniors. Journal of Gerontology: Medical Sciences, 65A, 1338-1343.

5 Ways to Focus on Brain Fitness

rlo — Thu, 28 Oct 2010 12:26:53 +0000

For pretty much all of us, developing brain fitness means doing something different. Either we have to do something we don’t do now, such as exercise or eat antioxidant-rich foods, or we have to do less of something we already do, such as eating high fat foods or just eating too much.

As a neuropsychiatrist, I often work with people who want to change something about themselves or their lives. And wanting to change raises the paradox we all face at times: we want to change, but we don’t.

The psychoanalysts used to have complex theories about why people do things that appear self-defeating. I think there’s a better answer: lack of focus. This may seem too simple, but attention is a complicated ability that is affected by things inside and outside of us.

When cognitive psychologists says that attention is a limited resource, they mean that you can only focus on a limited number of things at one time. Research has shown that even people who believe they are good at doing more than one thing at a time actually aren’t.

What does that have to do with change? In order to change, you have to be able to pay attention to what you’re doing and remember that you want to do something different. If you’re watching TV, it’s easy to eat an entire bag of chips. If you really pay attention to what you’re doing and at the same time remember that you want to lose 10 pounds, the chances are you will eat less. But when your attention is spent on the TV, your behavior becomes almost automatic (and probably outside of your awareness).

What can you do? Here are 5 ways to develop focus on what you want to change:

Start every day with 10 minutes of focused thinking or meditation. Break up the morning rush for just a few minutes so that you’ll have the change to reflect on your goals for the day.
Help yourself remember to pay attention. Recognize that you will forget or become distracted from your goals, and do something about it. In Aldous Huxley’s novel Island, birds were trained to help people to remember this point by repeatedly saying “Attention!” You may not have a mynah bird, but you can put a note on the bathroom mirror or a picture on the refrigerator to help you remember your goals.
Schedule a reminder in your phone or computer. Set it to pop up at a particular time or interval to remind you to stop for a few moments and review your goals, to meditate, or to relax.
Schedule time once a week for a more complete review of your goals at a time when you won’t feel rushed. Take some time to think about how well you’ve done during the preceding week, and focus on your goals for the coming week.
Try writing down personal brain fitness goals and keep the list somewhere that you will see without making a specific effort, such a door you walk through every day.

If you want to achieve something – whether it’s weight loss, increased exercise, or consistent brain training – you have to deploy some of your limited resource, attention. Finding ways to keep your goals in mind, every day, is a key.

Smoking and Brain Fitness

rlo — Tue, 26 Oct 2010 08:13:32 +0000

As though there wasn’t already enough evidence that smoking tobacco is bad for you, a new study shows a significant relation between smoking in your late 50’s and the chance of developing dementia about 20 years later. Smoking has multiple effects on your body, especially your heart, and this study again supports the idea that things that are bad for your heart are also bad for brain fitness.

The study published online in the Archives of Internal Medicine used data from more than 20,000 members of a health care organization. They completed surveys in the late 1970s to the early 1980s. The authors of the study looked at how many of them were later diagnosed with dementia.

Results showed that the risk of getting dementia (either Alzheimer’s disease or vascular dementia) increased steadily the more people reported smoking. For less than a pack a day, the increase was small and not statistically significant. But for larger amounts of smoking, the increased risk was significant, and for people smoking more than two packs per day, the risk was doubled.

This study once again shows that brain fitness is also cardiovascular fitness. The same things that cause clogged arteries around your heart may very well result in clogged arteries in your brain.

One good note: people who described themselves as former smokers had the same risk as those who never smoked. So quitting now may help reduce your risk later.

Reference:

Rusanen M et al (2010). Heavy smoking in midlife and long-term risk of Alzheimer disease and vascular dementia. Archives of Internal Medicine. Published online October 25, 2010. View the abstract here.