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Exercise: The best medicine06.29.2007 "Walk two miles and call me in the morning." That's what doctors could soon prescribe if the new leaders of two major medical groups have their way. "Walk two miles and call me in the morning."
More than half of Americans fail to get the 30 minutes of physical activity recommended daily to provide health benefits, according to the Centers for Disease Control and Prevention.
Written by Sally Squires/The Lean Plate Club
Originally published in the Boston Herald
Fast Food Without the Fat06.14.2007 Nancy Clark, the director of nutrition services at SportsMedicine Associates, talks about how you can eat well even less than optimal circumstances. It's no secret that fast-food places are not the bastion of healthy eating. But you can
eat at a fast-food place and fare relatively well. Almost every
fast-food establishment has at least one healthy (or healthier) choice.
But first, let's look at the potential problems if you enter the arena
of fast food mindlessly.
When you are in the "gulp-and-go" cycle, you may not give a second thought to what you put into your body. I find that even my health-conscious clients tend to fall into the all-or-none trap the moment they enter a fast-food restaurant. They rationalize, "Since I'm eating fast food, I might as well blow it." This mind-set combined with the ease of ordering combo meals and their inexpensive supersizing can quickly spell trouble. Even if you are not supersizing, some foods by themselves exceed a day's worth of fat and sodium if you eat the whole thing. If you want to see how your favorite fast-food order stacks up nutritionally, check out appendix A, "Fast-Food Nutritional Charts." You'll find nutrition information on 22 fast-food companies, including pizza places, sandwich shops, and take-out places. Now let's focus on the positive, that is, how to make the best out of a fast-food situation. Keep in mind that in a pinch, fast food can be better than going too long without eating, which can lead to overeating. Here are some guidelines to help make the best of your fast-food order.
Excerpted with permission from Nancy Clark's Sports Nutrition Guidebook, by Nancy Clark, Human Kinetics
Publishers, Inc.
Women's midlife weight key to future diabetes risk06.14.2007 People carrying excess weight who aim to ward off diabetes should try to lose the pounds before they reach middle age, Australian researchers suggest. NEW YORK
(Reuters Health) - People carrying excess weight who aim to ward off
diabetes should try to lose the pounds before they reach middle age,
Australian researchers suggest.
A
woman's body mass index (BMI) in her late 40s was the strongest
predictor of her risk of developing diabetes over the next eight years,
Dr. Gita D. Mishra of the University of Queensland and her colleagues
found.
On the other hand, there was no link between weight change in subsequent years and the likelihood of becoming diabetic.
While
excess weight is understood to boost the risk of developing type 2
diabetes, the effects of shorter-term weight gain or loss are not as
clear, Mishra and her team note in the journal Diabetes Care. To
investigate, the researchers followed 7,239 women for 8 years. Study
participants were 45 to 50 years old when the study began, and they
completed surveys on their health at the study's outset in 1996 and in
1998, 2001 and 2004.
Those
with BMIs of 25 or greater, indicating they were overweight or obese,
in 1996 were at the highest risk of developing type 2 diabetes by 2004,
the researchers found. Very obese women with BMIs of 35 or above were
12 times more likely than their normal-weight peers to become diabetic.
Weight gain
or loss during the course of the study had no influence on a woman's
risk of developing diabetes, while physical activity only reduced risk
for the most active women.
"Because
women's risk of developing type 2 diabetes in midlife is more closely
related to their initial BMI (when aged 45-50 years) than to subsequent
short-term weight-change, public health initiatives should target the
prevention of weight gain before and during early adulthood," the
researchers conclude.
They
note that only small changes in physical activity and calorie intake
are needed to stop from becoming overweight or obese, and that it is
particularly important to "inspire people" to make those changes while
they are young adults.
Diabetes Care, June 2007 and reproduced by Reuters Health. Tips from the trainer: SIMPLE FITNESS TIPS TO HELP YOU LOOK AND FEEL YOUR PERSONAL BEST06.14.2007 Expert advice from Gold's Gym Senior Fitness Manager Karyna Elizondo Did you know that proper hydration can help you burn fat? Or that lifting weights can help you lose weight? Gold's Gym Senior Fitness Manager, Karyna Elizondo, provides seven simple tips and facts to help clarify some of the basics of working out and losing weight.
Set Goals - Be sure to set specific, clear and concise goals. Proper goal setting is the key to success when starting a fitness program. Variation - Program design and exercise variation is a key component to getting results. Change up your workout routine every three to four weeks to get better results. Lift to Lose - Lifting weights helps you lose weight. Resistance training increases lean muscle; lean muscle burns more calories. Know When to Stop - Too much cardio can burn lean muscle and slow down your metabolism. Eating to be Thin - Eat five to six small meals a day to keep your metabolism going and avoid hunger pains. Proper Nutrition - Following the right meal plan is 70%-80% of accomplishing your fitness goals. Your body adapts to any diet just as it would a workout program. Water it Down - The proper amount of daily water intake will help burn more fat. Learning How to Eat05.31.2007 Nancy Clark, the director of nutrition services at SportsMedicine Associates, offers real-world advice on eating and nutrition. If diets worked, then everyone who has ever gone on a diet would be
thin. That's not what happens. Most dieters are heavy. Hence, the way
to lose weight for the long haul is to learn how to eat healthfully and
appropriately. In chapter 1 I talked about using the Food Guide Pyramid
to guide healthful food choices. In this chapter I'll build on that
information to help you choose the right portions at the right times so
that you can lose weight without feeling denied or deprived. I'll teach
you nutrition skill power, which is more powerful than the willpower
you might yearn for. Such was the case with Roberta, a 42-year-old
computer programmer, mother of two teenagers, and fitness runner.
"If only I had more willpower, I could lose weight," Roberta complained. "I've been trying to lose these same 8 to 10 pounds for 12, yes 12! years. I'm the diet queen!" Feeling completely helpless, Roberta came to me as a last resort to help her achieve her weight goals. When reviewing her dieting history, I noticed that Roberta would diet by trying to exist on fruit for breakfast, salads for lunch, yogurt for a snack, and fish with vegetables for dinner. Her intake was spartan, to say the least, and it included a limited variety of food. I asked, "When you are not dieting, what do you eat?" She quickly listed her favorite foods (what she fed her children): cereal for breakfast, peanut butter and jelly sandwich for lunch, spaghetti for dinner. Every time she went on her diet to lose weight, she denied herself these favorite foods. She went to extremes to keep cereal and peanut butter out of her sight so that she wouldn't eat them. She deemed them too much temptation for her weak willpower, so she had her kids hide them from her. I encouraged Roberta to stop looking at food as being fattening and instead enjoy satisfying meals. Eating good food, after all, is one of life's pleasures. Given that she had liked cereal, breads, and pasta since childhood, she was naive to think she could stop liking them. Instead of trying to keep these foods out of her life, I encouraged her to eat them more often. I pointed out that her standard diet foods (fruit, salad, and fish) had no power over her because she gave herself permission to eat them whenever she wanted. I encouraged her to eat cereal every day for breakfast (and even lunch, dinner, and snacks) to take the power away from that food, and I simultaneously taught her how to manage eating cereal in an appropriate portion. If you, too, struggle with weight issues, you need to learn how to manage your favorite foods, not how to deny yourself of them. By enjoying appropriate portions of whatever you'd like to eat, as often as you'd like, you no longer need willpower to avoid them. Nutrition skill power, not willpower, enhances permanent weight loss without denial and deprivation. One skill that enhances your ability to eat appropriate food portions is to eat mindfully (not mindlessly). That is, chew the food s-l-o-w-l-y, taste it, and savor each mouthful. By doing so, you'll need far less quantity to be satisfied, and you'll be content to eat a smaller portion. By mindfully eating your favorite foods, you will also diffuse the urge to do last-chance eating. (You know, "Last chance to eat peanut butter and jelly sandwiches before I go back on my diet. I'd better have another one!") You can enjoy more peanut butter (or whatever) when your body becomes hungry again. Nutrition skill power wins in the end. A second skill that enhances weight loss is to choose more fruits, vegetables, unrefined grains, and fiber-rich foods that have low glycemic response, that is, that have the smallest effect on blood glucose (see chapter 7). Carbs with a low glycemic index (GI) promote weight loss by promoting satiety and delaying a return of hunger, which contributes to eating less in subsequent meals. High-glycemic carbs (that is, sugary sweets) produce the opposite effect. They trigger the release of more insulin, which can induce hunger and favor storage of fat. Calorie for calorie, low-glycemic fruits, veggies, and whole grains are more satiating than are high-glycemic sodas, lollipops, and gummy bears. You still need to limit calories, but you can feel fuller on calories from low-glycemic foods. By regularly choosing low-GI carbs, you'll not only lose weight more easily but also maintain that weight loss more easily. Furthermore, the diet is rich in the foods that can reduce your risk of cancer, heart disease, and hypertension and are consistent with the U.S. dietary guidelines for healthy eating. Excerpted with permission from Nancy Clark's Sports Nutrition Guidebook, by Nancy Clark, Human Kinetics
Publishers, Inc.
Just 10 Minutes of Daily Exercise Boosts Heart Health05.31.2007 Study finds a little exercise provides cardiovascular benefits, and more is even better A new study has good news for
those who've been avoiding exercise because they don't think they have
enough time: Even 10 minutes a day can improve your cardiovascular
fitness.
The research found that when overweight or obese, sedentary women
started to exercise an average of 72 minutes a week, they increased
their peak oxygen consumption -- a measure of cardiovascular fitness --
by 4.2 percent compared to women who stayed on the sidelines.
"For people who've been really sedentary, you're getting a benefit
almost immediately. Just get off the couch," advised the study's lead
author, Dr. Timothy Church, director of the Laboratory of Preventive
Medicine Research at the Pennington Biomedical Research Center at
Louisiana State University.
"It was surprising to us, the idea that as little as 10 to 15
minutes of exercise a day could provide benefit in terms of fitness,"
he added.
The researchers also found that while a little bit of exercise was
beneficial, more exercise boosted cardiorespiratory fitness even
higher.
Church noted that the intensity of exercise the women in the study
engaged in was very low, probably equivalent to walking at a speed of
about 2 to 3 miles an hour.
The findings are published in the May 16 issue of the Journal of the American Medical Association.
"Physical activity is clearly beneficial for your health. This study
shows that any activity is good, and more is better," said Dr. I-Min
Lee, an associate professor of medicine at Brigham and Women's Hospital
and Harvard Medical School, both in Boston. Lee wrote an accompanying
editorial in the same issue of the journal.
Church and his colleagues undertook the research, because there have
been few studies that have looked at the dose-response effect of
exercise -- that is, how much exercise do you need to see a benefit and
will more exercise continue to produce additional benefits?
To answer those questions, the researchers recruited 464
postmenopausal women who were considered overweight or obese. All of
the women had some degree of high blood pressure, and none was
exercising at all at the start of the study.
The women were randomly assigned to one of four groups: the control
group that would remain sedentary; a light exercise group that averaged
72 minutes a week of exercise; a moderate exercise group that averaged
about 136 minutes a week; and a high exercise group that completed
nearly 192 minutes of exercise each week.
Current recommendations call for 30 minutes of exercise most days of
the week. Church said the three exercise groups roughly translate to 50
percent, 100 percent and 150 percent of the exercise guideline.
The researchers measured the women's peak oxygen consumption at the
start of the study, and then again after six months of exercise. They
found that the women in the light exercise group increased their peak
oxygen consumption levels by 4.2 percent. The moderate exercise group
saw a 6 percent rise, while the heavy exercise group upped their
cardiorespiratory fitness by 8.2 percent.
"This is great news for couch potatoes and for the aging," said
Church. "There are people that can't obtain the recommendations for
exercise, but now, we see if you can't get 150 minutes a week, you
stand to benefit even if you get half that."
Lee said: "These findings suggest that different outcomes may show
different responses. Even with a little bit of physical activity, there
was a significant improvement in physical fitness. And, this study
showed that as the dose increased, you saw commensurate increases in
fitness.
"With a very doable dose of physical activity, you can start seeing health benefits," Lee added. Written by Serena Gordon
Originally published at HealthDay News
Copyright © 2007 ScoutNews, LLC. All rights reserved. Strength training may reverse muscle aging05.31.2007 Genetic tests shows it reverses aging process in elderly tissues It's
well known that resistance exercises improve muscle strength and
function in young and old alike, but the new research suggests that
strength training also affects older muscles on the level of gene
expression - essentially turning back the clock on muscle aging.
The
study, published in the online journal PLoS One, looked at whether
strength training affects the "gene expression profile" in older
adults' muscle. Genes hold the instructions from which the body
manufactures proteins; gene expression refers to the processes that
translate these instructions into proteins.
Analyzing small
samples of muscle tissue from a group of healthy young and older
adults, researchers found that older and younger muscle tissues
differed significantly in their gene expression profiles. The
difference indicated that older muscle tissue had impaired functioning
in mitochondria -- structures within cells that act as the cell's
"powerhouse."
That impairment was reversible, however. After 14
of the older adults underwent 6 months of strength training, the gene
expression profile in their muscles showed a more youthful appearance.
"In
a very real sense, the muscle was younger," said lead study author Dr.
Simon Melov of the Buck Institute for Age Research in Novato,
California.
Experts have long known that exercise is good for
younger and older adults alike, Melov told Reuters Health, but the new
findings suggest that it can "actually rejuvenate muscle" in older
individuals.
The study included 25 healthy men and women older
than 65, and 26 healthy adults ages 20 to 35 who had diet and exercise
habits similar to the older group. By analyzing muscle tissue from each
volunteer, Melov's team found age-related differences in the expression
of hundreds of genes - such that mitochondrial function in older
adults appeared "dramatically impaired."
Fourteen of the older adults then went through a strength training program, working out two days a week for 6 months.
As
expected, the researchers found that these volunteers boosted their
muscle strength, coming closer to their younger counterparts'
performance. But their muscle also showed a turnaround in gene
expression that Melov described as surprisingly stark.
He said
more studies are needed to see whether aerobic exercise, like walking
or cycling, has similar effects on muscle - and whether exercise might
reverse molecular aging in other types of body tissue.
For now, the researchers say, their findings show that it's never too late to start exercising.
Written by Amy Norton
Originally published by PLoS One and Reuters Health
PROPER STRETCHING TECHNIQUES FOR A HEALTHIER BODY05.18.2007 The Fitness Institute's Michelle LeMay shares expert advice on stretching. Stretching is an essential component of an exercise routine. However, recent studies reveal that most people do not incorporate enough stretching exercises into their fitness programs. Gold's Gym Fitness Institute Member, world-renowned Mind/Body Specialist, and author of Essential Stretch: Gentle Movements for Stress Relief, Flexibility and Overall Well-being, Michelle LeMay, shares her expert advice on the best stretching exercises to increase flexibility and decrease stress and tension.
Stretch before and after exercising. Prior to working out, it is important to assess the type of fitness activity, activity level and an understanding of which body parts are tight. In general, it is important to stretch the neck, back, torso, hips and legs. Specifically, LeMay recommends performing the following stretches before working out: Spinal Rolls (straight forward and diagonal - left and right), Standing Side Sways (alternating on each side), Standing Quad Stretches and Standing Calf Stretches. "Once your workout is complete, it is extremely important to perform cool down exercises to decrease muscle tension and increase your flexibility," explains LeMay. Sample cool down stretches include: Rocking Forward Bends, Hip Openers, Straddle Stretches and Spinal Twists. Stretching keeps the muscles elongated. As you workout, you put physical stress on your body to strengthen your muscles. In that process your body can become tight and somewhat constricted. "Treating your body to a nurturing stretch elongates and opens up your muscles to receive oxygen and blood nutrients and to eliminate waste," proclaims LeMay. "This helps keep your muscles clean, balanced, strong and healthy." There are many health benefits associated with stretching regularly. The benefits include: reduced stress, tension and anxiety, increased mind/body awareness, improved circulation, increased energy levels, reduced risk of injuries and improved posture, just to name a few. In addition, "Stretching makes you feel, look and move better," says LeMay. Example warm-up stretches:
Straight Forward Spinal Roll: Example cool-down stretches:
Energizing Your Exercise05.14.2007 Nancy Clark, the director of nutrition services at SportsMedicine Associates, talks about the benefits of snacking for a workout. Snacking before you exercise will help energize your workout. A preexercise snack has four main functions:
Yet many people purposefully exercise on empty because they believe that exercising without having eaten beforehand enhances fat burning. True, but they assume that by burning more body fat, they will lose more body fat. False. To lose body fat, you need to create a calorie deficit by the end of the day. Whether you burn carbs or fats has less to do with losing body fat than it does with your calorie balance at the end of the day. The truth is you'll be able to exercise harder and burn more calories if you eat a preexercise snack. The harder exercise might contribute to the desired calorie deficit. Many people are also afraid that preexercise food will result in an upset stomach, diarrhea, and sluggish performance. Of course, too much of the wrong kinds of foods can cause intestinal problems, but lack of fuel is more often the cause of sluggish performance. Morning exercisers, in particular, need to be sure they have fueled themselves adequately, even if they work out before breakfast. Snacks Before Morning Workouts Skipping breakfast is a common practice among people who exercise in the morning. If you roll out of bed and eat nothing before you jump into the swimming pool, participate in a spinning class, or go for a run, you may be running on fumes. You will probably perform better if you eat something before you exercise. During the night, you can deplete your liver glycogen, the source of carbohydrates that maintains normal blood sugar levels. When you start a workout with low blood sugar, you fatigue earlier than you would have if you had eaten something. How much one should eat varies from person to person, ranging from a few crackers to a slice of bread, a glass of juice, a bowl of cereal, or a whole breakfast. If you've had a large snack the night before, you'll be less needy of early morning food. But if you've eaten nothing since a 6:00 P.M. dinner the night before, your blood sugar will definitely need a boost. Most people feel good results with 0.5 grams of carbohydrate (2 calories) per pound (1 gram per kilogram) of body weight one hour before moderately hard exercise, and 2 grams of carbohydrates (8 calories) per pound (4 grams per kilogram) of body weight four hours before-hand. For a 150-pound (68-kilogram) person this is 75 to 300 grams (300 to 1,200 calories) of carbohydrates-the equivalent of a small bowl of cereal with a banana to a big stack of pancakes (ACSM et al. 2000). Defining the best amount of preexercise food is difficult because tolerances vary greatly from person to person. Some athletes get up an hour early just to eat and then go back to bed and allow time for the food to settle. Others have a few bites of a bagel, a banana, or some other easy-to-digest food as they dash out the door. Then there are those who habitually run on empty. If that's you, an abstainer, here is a noteworthy study that might convince you to experiment with eating a morning snack before you work out. Researchers asked a group of athletes to bike moderately hard for as long as they could. When they ate breakfast (400 calories of carbohydrates) 3 hours before the exercise test, they biked for 136 minutes, as compared with 109 minutes with only water (Schabort et al. 1999). Clearly, these athletes were able to train better with some gas in their tank. Preexercise morning fuel will likely work for you, too! Four hundred calories is the equivalent of an average bowl of cereal with some milk and banana; it's not a pile of pancakes. You need not eat tons of food to notice a benefit; some food is helpful but more food may not be better. Eat what's comfortable for you and learn what is the right amount to fuel your workouts but still settle well. Snacks Before Afternoon Workouts Joe, an afternoon runner, wondered if eating a bagel at 3:00 would provide energy for his 4:00 workout or simply sit in his stomach. I explained that, despite popular belief, the food one eats before a workout is digested and used for fuel during exercise. The body can indeed digest food during exercise, as long as you are exercising at a pace you can maintain for more than 30 minutes. Cyclists who ate 300 calories before exercise absorbed all 300 calories during the hour of moderate to somewhat hard exercise (Sherman, Pedan, and Wright 1991). If Joe were to do extremely intense sprint activity such as a track workout or time trial, the food would be more apt to sit in his stomach and talk back to him. During intense exercise the stomach shuts down so that more blood can flow to the muscles. Therefore, you need to plan your schedule and eat a hearty lunch at noon if you will be doing a hard workout at 4:00 (with no preexercise snack because of the intensity of the workout). Here is a second study that demonstrates the importance of eating before you exercise. In this study cyclists ate either nothing or 1,200 calories of carbohydrates (two grams of carbohydrates per pound of body weight) four hours before an exercise test to exhaustion. When they ate the 1,200-calorie meal they were able to bike 15 percent harder during the last 45 minutes, as compared with when they ate nothing. Given that road races and many competitive events are won or lost by fractions of a second, to be 15 percent stronger offers a huge advantage (Sherman et al. 1989). The carbohydrates the cyclists ate before they exercised supplied extra fuel for the end of the workout, when their glycogen stores were low. Although these studies looked at cyclists, who tend to report fewer gastrointestinal complaints than do athletes in running sports that jostle the stomach, the benefits are worth noting. If you've always exer-cised on an empty stomach, you may discover that you can exercise harder and longer with an energy booster. Experiment during training with eating some carbohydrate-based snacks within a few minutes to four hours before you exercise. If you swim at 6 A.M., munch on a bagel on the way to the pool. If you work out at lunch, be sure to eat carbs such as cereal for breakfast and a banana for a 10 A.M. snack. If you exercise after work, have a substantial lunch and then a yogurt and energy bar for a second lunch later that afternoon. What's the Best Time to Eat? The trick to completing your workout with energy to spare is to fuel up at the right time before the event. Here are some suggestions for different types of events at different times of the day. Time: 8 A.M. event, such as a road race or swim meet Meals: Eat a high-carbohydrate dinner and drink extra water the day before. On the morning of the event, about 6:00 or 6:30, have a light 200- to 400-calorie meal (depending on your tolerance), such as yogurt and a banana or one or two energy bars, tea or coffee if you like, and extra water. Eat familiar foods. If you want a larger meal, consider getting up to eat by 5:00 or 6:00. Time: 10 A.M. event, such as a bike race or soccer game Meals: Eat a high-carbohydrate dinner and drink extra water the day before. On the morning of the event, eat a familiar breakfast by 7:00 to allow three hours for the food to digest. This meal will prevent the fatigue that results from low blood sugar. If your body cannot handle any breakfast, eat a late snack before going to bed the night before. The snack will help boost liver glycogen stores and prevent low blood sugar the next morning. Time: 2 P.M. event, such as a football or lacrosse game Meals: An afternoon game allows time for you to have either a big, high-carbohydrate breakfast and a light lunch or a substantial brunch by 10:00, allowing four hours for digestion time. As always, eat a high-carbohydrate -dinner the night before and drink extra fluids the day before and up to noon. Time: 8 P.M. event, such as a basketball game Meals: You can thoroughly digest a hefty, high-carbohydrate breakfast and lunch by evening. Plan for dinner, as tolerated, by 5:00 or have a lighter meal between 6:00 and 7:00. Drink extra fluids all day. Time: All-day event, such as a hike, 100-mile bike ride, or triathlon training Meals: Two days before the event, cut back on your exercise. Take a rest day the day before to allow your muscles the chance to replace depleted glycogen stores. Eat carbohydrate-rich meals at breakfast, lunch, and dinner (see chapter 7 for information about carbo loading). Drink extra fluids. On the day of the event, eat a tried and true breakfast depending on your tolerance. While exercising, at least every 1 1/2 to 2 hours plan to eat carbohydrate-based foods (energy bars, dried fruit, sports drinks) to maintain normal blood sugar. If you stop at lunchtime, eat a comfortable meal, but in general try to distribute your calories evenly throughout the day. Drink fluids before you get thirsty; you should need to urinate at least three times throughout the day. Excerpted with permission from Nancy Clark's Sports Nutrition Guidebook, by Nancy Clark, Human Kinetics
Publishers, Inc.
Study shows why exercise boosts brainpower05.14.2007 Exercise boosts brainpower by building new brain cells in a brain region linked with memory and memory loss. Exercise boosts brainpower by building new brain cells in a brain region linked with memory and memory loss, U.S. researchers reported. Tests on mice showed they grew new brain cells in a brain region called the dentate gyrus, a part of the hippocampus that is known to be affected in the age-related memory decline that begins around age 30 for most humans. The researchers used magnetic resonance imaging scans to help document the process in mice - and then used MRIs to look at the brains of people before and after exercise. They found the same patterns, which suggests that people also grow new brain cells when they exercise. "No previous research has systematically examined the different regions of the hippocampus and identified which region is most affected by exercise," Dr. Scott Small, a neurologist at Columbia University Medical Center in New York who led the study, said in a statement. Writing in the Proceedings of the National Academy of Sciences, the researchers said they first tested mice. Brain expert Fred Gage, of the Salk Institute in La Jolla, California, had shown that exercise can cause the development of new brain cells in the mouse equivalent of the dentate gyrus. The teams worked together to find a way to measure this using MRI, by tracking cerebral blood volume. "Once these findings were established in mice, we were interested in determining how exercise affects the hippocampal cerebral blood volume maps of humans," they wrote. They of course could not dissect the brains of people to see if new neurons grew, but they could use MRI to have a peek. They recruited 11 healthy adults and made them undergo a three-month aerobic exercise regimen. They did MRIs of their brains before and after. They also measured the fitness of each volunteer by measuring oxygen volume before and after the training program. Exercise generated blood flow to the dentate gyrus of the people, and the more fit a person got, the more blood flow the MRI detected, the researchers found. "The remarkable similarities between the exercise-induced cerebral blood volume changes in the hippocampal formation of mice and humans suggest that the effect is mediated by similar mechanisms," they wrote. "Our
next step is to identify the exercise regimen that is most beneficial
to improve cognition and reduce normal memory loss, so that physicians
may be able to prescribe specific types of exercise to improve memory,"
Small said.
Originally published by Reuters
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