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Aging, Health and Fitness, Neuroscience, Public Health, Research

Neighborhood’s “walkability” helps older adults maintain physical and cognitive health

Neighborhood’s “walkability” helps older adults maintain physical and cognitive health

3275748024_c4914d4ae0_zLiving in a walkable neighborhood could be an important factor in helping older adults maintain their physical and cognitive health, according to new research from the University of Kansas.

In the small study, researchers monitored a group of adults diagnosed with mild Alzheimer’s disease and compared them to those without any cognitive impairment. Over a two-year period, individuals completed cognitive tests designed to measure attention, verbal memory and mental status. The ”walkability” of participants’ neighborhoods was determined using geographic information systems (GIS). Medical News Today reports:

Results from the study suggest that communities that are easier to walk in are linked to better physical health outcomes – such as lower body mass and blood pressure – and cognition – including better memory.

[Researchers] believe their findings could benefit older adults, health care professionals, caregivers and even architects and urban planners.

Finding also showed that environments with more complex layouts appeared to aid residents in staying mentally sharp, rather than confusing them. Researchers presented their findings over the weekend at the Gerontological Society of America’s annual meeting in Washington, DC.

Previously: Walking and aging: A historical perspective, Even old brains can stay healthy, says Stanford neurologist,  Exercise and your brain: Stanford research highlighted on NIH Director’s blog , Moderate exercise program for older adults reduces mobility disability, study shows and Creating safer neighborhoods for healthier lifestyles
Photo by Ed Yourdon

Ask Stanford Med, Chronic Disease, Events, Health and Fitness

Examining the role of exercise in managing and preventing diabetes

Examining the role of exercise in managing and preventing diabetes

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More than 29 million adults and children in the United States are living with diabetes, and it’s estimated (.pdf) that an additional 86 million Americans ages 20 years or older have prediabetes, putting them at increased risk of developing the disease.

The good news is that lifestyle modifications can be an effective method for managing or preventing diabetes. In recognition of National Diabetes Month, I reached out to Baldeep Singh, MD, a clinical professor at Stanford who focuses on chronic disease management, to discuss the importance of regular physical activity for patients diagnosed with diabetes and those working to limit their risk of developing the disease. This Thursday, Singh will explore the topic more in-depth during a Stanford Health Library event at the Arrillaga Alumni Center on campus, where attendees can also have their blood glucose checked. The discussion will also be webcasted for those unable to attend in person.

In this Q&A, Singh highlights scientific evidence showing that staying active has a beneficial effect on insulin sensitivity, and discusses the potential of exercise, in combination with other behavioral changes, to induce partial, or full, remission of type 2 diabetes.

How does regularly exercising help in preventing or delaying type 2 diabetes?

The benefit of exercise in preventing diabetes has been demonstrated in several studies. A meta-analysis of 10 studies of physical activity and type 2 diabetes reported a lower risk of developing diabetes with regular moderate physical activity, including brisk walking, compared with being sedentary

Additionally, in a subsequent prospective cohort study in men, either weight training or aerobic exercise for at least 150 minutes per week was associated with a lower risk of developing type 2 diabetes compared to those with  a control group who did no physical activity.

Why is engaging in physical activity important in managing type 2 diabetes?

In patients with type 2 diabetes, studies show that short-term exercise training improves insulin sensitivity just as it does in non-diabetics. In patients with type 2 diabetes treated with medication, exercise tends to lower blood glucose concentrations.

Exercise improves glycemic control in patients with type 2 diabetes, as illustrated by the findings of several meta-analyses of trials examining the effect of exercise on glycemic control in patients with type 2 diabetes. Exercise training reduces glycosylated hemoglobin (A1C) values by approximately 0.5 to 0.7 percentage points compared with control participants.

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Health and Fitness, In the News, Research, Sleep, Stanford News

Superathletes sleep more, says Stanford researcher

Superathletes sleep more, says Stanford researcher

alarm-clock-146469_640Hit snooze again – it just might boost your performance, Stanford sleep expert Cheri Mah believed. Seems intuitive, yet research findings were needed.

Mah originally tapped Stanford’s men’s basketball team to test her theory. When the team went from an average of 6.5 to 8.5 hours of sleep a night, they hit 11 percent more free throws and sprinted more quickly. Her work grabbed headlines at the time, and now it’s featured in Mark McClusky’s  forthcoming book, Faster, Higher, Stronger: How Sports Science is Creating a New Generation of Superathletes — and What We Can Learn from Them.

The Atlantic excerpted a key section from the book today; here’s McClusky (who also edits Wired.com):

For us humans, sleep is completely crucial to proper functioning. As we’ve all experienced, we’re simply not as adept at anything in our lives if we don’t sleep well…

It seems like certain kinds of athletic tasks are more affected by sleep deprivation. Although one-off efforts and high-intensity exercise see an impact, sustained efforts and aerobic work seem to suffer an even larger setback. Gross motor skills are relatively unaffected, while athletes in events requiring fast reaction times have a particularly hard time when they get less sleep.

McClusky goes on to write that Mah’s research “strongly suggests that most athletes would perform much better with more sleep – if they could get it.” But it’s tricky for top athletes to get enough sleep. Fly across the country, or the world, and your sleep schedule is skewered. And West Coast teams have it particularly hard:

In 2013, the Seattle Mariners flew more than 52,000 miles while the Chicago White Sox, with their central location and nearby division rivals, only flew about 23,000… Bouncing around the country, leaving late, arriving early, having to play the next day—it’s no surprise that travel and the management of sleep is a huge problem for athletes.

Some athletes squeeze in an afternoon nap to boost their rest times, McClusky said. And that sounds like a mighty fine idea to me.

Previously: Ask Stanford Med: Cheri Mah responds to questions on sleep and athletic performance, Expert argues that for athletes, “sleep could mean the difference between winning and losing,” Why your sleeping habits may be preventing you from sticking to a fitness routine and A slam dunk for sleep: Study shows benefits of slumber on athletic performance
Image by OpenClips

Applied Biotechnology, Health and Fitness, Stanford News

Fits like a glove: Stanford researchers develop medical applications for the Cooling Glove

Fits like a glove: Stanford researchers develop medical applications for the Cooling Glove

Weightlifting1-CoreControlTwo years ago we wrote about the Cooling Glove, a device developed by Stanford biologists Craig Heller, PhD, and Dennis Grahn that helps athletes cool off and recover from active play more easily. At the time, the Cooling Glove was being used by a few sports teams, especially Stanford football, but others included the San Francisco 49ers and Manchester United. This past July, the glove was used by the Germans in the FIFA World Cup soccer competition, where they handily beat the heavily favored Brazilian team on their home turf.

The device fits over an athlete’s hand and is connected to a cooler and a vacuum source. Grahn and Heller’s major insight was that the non-hairy skin of the palms, soles, and face are our major sites of heat dissipation. These areas have special blood vessels that can receive a large volume of blood and act as radiators, and the cooled blood from these surfaces flows back to the body’s core.

When asked about other applications for the glove, Heller rattles off half a dozen that his lab is looking into in quick succession. One includes building a prototype for military working dogs. If they’re in an extremely hot climate, they pant more, which compromises their ability to sniff and find the dangerous compounds they are searching for. A canine cooling device that keeps their body temperature cool can help their sniffers work more efficiently.

The team is also working on several medical applications. One variant aims to maintain patient’s temperature during surgery. In this application, booties can be used leaving the arms free for IV lines and other instrumentation. The researchers are also looking at how the Cooling Glove can help menopausal women manage their hot flashes. Heller will soon begin enrolling volunteers for this trial. Another application involves using the glove in its heating mode to stave off migraine headaches before they become full-blown.

The U.S. Department of Energy is interested in how personal heating and cooling devices could be used as an alternative to heating and cooling whole buildings or rooms. The glove or bootie technology could mean a broader dead band on thermostats – the temperature range within which neither the cooling or heating system needs to be turned on – thus saving lots of energy.

Despite the recent success at the World Cup, Heller says the Cooling Glove has not been as popular with athletes as it could be. He notes that Avacore, the company marketing the glove commercially, is relatively small and doesn’t have a large enough budget to develop a more streamlined and user-friendly version or market it widely. He says that the device’s novelty also slows down acceptance:

If you have a concept that doesn’t fit existing ideas, breaking into a market is difficult. We had to overcome skepticism that we were selling snake oil. We overcome that with research, but getting basic research translated and disseminated for the user community is not easy.

One finding of the research is that use of the glove in a conditioning program produces impressive results – beyond what is produced by performance enhancing substances, such as steroids. In a study involving students, some freshmen women – not varsity athletes – were did more than 800 pushups in less than 45 minutes. Some professional athletes tripled their capacities in particular routines such as dips or pullups in 5-6 weeks.

Heller is optimistic about the Cooling Glove’s future in sports. “I expect it will be adopted eventually. If, for no other reason, safety – in sports and many other endeavors such as emergency response.”

Heller is a founder of Avacore, but no longer affiliated with the company.

Previous: Researchers explain how “cooling glove” can improve exercise recovery and performance
Photo courtesy of Avacore

Health and Fitness, Nutrition

Eat well, be well and enjoy (a little) candy

Eat well, be well and enjoy (a little) candy

260823789_3eda4b0439_oAs Halloween treats fill cupboards, jack-’o-lanterns and workplace counters, I bet you’re hunting for a middle ground between candy glutton and candy curmudgeon. Anticipating this tricky balance, Stanford dieticians Rosalyne Tu, MS, RD and Raymond Palko, MS, RD, offered some healthy eating tips in this BeWell@Stanford feature:

What are some common pitfalls during the holidays that can contribute to weight gain?

RP: Often, the concept of “moderation” can undermine our good intentions. Moderate eating does not mean consuming two pieces of pumpkin pie instead of three. Rather, it means having a small slice of pie, one or two times over the course of a week.

RT: Sometimes we are too “good” about budgeting our calories and we skip meals or under-eat during the day to save up calories for large holiday meals. This strategy can backfire on us because our appetite hormones get very strong and we end up in less control of our appetites, causing us to overeat later. Our bodies were designed to treat starvation as our worst enemy; therefore, when we are hungry, we naturally crave highly caloric foods (high sugar and fat). For some people, giving in to these foods brings on feelings of guilt when the biological response was natural.

RP: Increased alcohol consumption is another road bump. At parties, alcohol can flow freely, and it is very calorically dense without any nutritional benefits.

RT: Liquid calories are often empty calories. Alcohol, specifically, can promote overeating because of its ability to break down willpower while causing blood sugars to drop — both of which could encourage overeating.

But it’s still possible to enjoy your favorite treats, the two dieticians said:

RT: Food is meant to be enjoyed! Give yourself permission to enjoy your favorite treat and practice eating mindfully. Eat your treat like it is a fine dining experience: slow down, savor every morsel, and minimize the distractions like the television and computer. Eating mindfully helps your body decide how much it is truly hungry for.

Previously: When it comes to weight loss, maintaining a diet is more important than diet type, Where is the love? A discussion of nutrition, health and repairing our relationship with food and How to avoid a candy-coated Halloween
Photo by Juushika Redgrave

Ask Stanford Med, Health and Fitness

Director of Stanford Runner’s Injury Clinic discusses treating and preventing common injuries

Director of Stanford Runner's Injury Clinic discusses treating and preventing common injuries

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It may surprise you to learn that past studies show that runners have a 50 percent chance of sustaining an injury that disrupts their training, and those that compete in marathons have an incidence rate as high as 90 percent. But don’t hang up your sneakers just yet. Many common aches and pains that nag runners can easily be treated or avoided.

On Thursday, Michael Fredericson, MD, who is director of the Stanford Runner’s Injury Clinic and has been head team physician with the Stanford Sports Medicine Program since 1992, will talk about the latest running prevention and treatment methods during a Stanford Health Library lecture. (For those unable to attend the event in person, you can watch the live webcast starting at 7 PM Pacifiic time.) To kick off the conversation, I reached out to Fredericson to discuss some of the topics of his upcoming talk, including the harms of overstriding, the benefits of cross-training, and remedies for prevalent joint problems. He and Adam Tenforde, MD, a sports medicine fellow at Stanford, responded to my questions.

How can overstriding lead to injury?

The term “overstriding” refers to running with the foot striking the ground too far forward from normal stride length. This results in heel strike pattern that may increase stress in the hip and knee joints. Research has shown that forefoot strike patterns tend to reduce stress on the knees and hips, although this may lead to greater stress on the foot and ankle. We conduct a clinic called RunSafe, where we evaluate gait of runners using video and markers. More efficient stride frequency is 90 strides per leg per minute. When a runner overstrides, this may result in a lower stride rate and an inefficient gait. We evaluate for the causes of overstriding, including poor hip extensor strength (weak gluteal muscles), decreased flexibility and technique and encourage correction of these biomechanical contributors. Also, we may suggest shoes with reduced weight, such as ‘minimalist shoes’ as these tend to encourage a runner to run with a more mid-foot strike pattern. However, we caution any changes in shoe type or technique be introduced gradually to decrease risk of developing an injury from changes in gait pattern that stress the body in a new way.

Why is it important for runners to cross-train?

Cross-training refers to forms of aerobic exercise that do not involve running. Doing exercises that do not involve the repetitive ground-impact experienced during running help to rest tired muscles and decrease stress on bones, assisting in recovery while building aerobic capacity. There are no established forms of cross-training to prevent injuries, but performing exercises that do not involve impact loading through the legs, such as elliptical trainer, cycling or deep water running may be helpful.

Many runners select shoes that compensate for how their foot pronates. But recent research shows that pronating too much or too little may not actually increase a runner’s risk of injury. How important is pronation and foot type in preventing injuries?

We evaluate foot type and pronation during our RunSafe clinics. Pronation is a normal motion that helps to distribute forces while landing through the foot and ankle, reducing stresses through the lower extremities. If the foot abruptly stops moving from too much or too little pronation, the other joints and lower limbs may absorb these forces and can become injured. Foot type (having too high an arch or too flat a foot) may also result in higher forces in the legs and joints through associated biomechanics. Foot type and concerns of pronation need to be put into context of prior injury history, as recent research has suggested that foot type and pronation do not necessarily predict future injury risk.

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Aging, Health and Fitness, History, Neuroscience

Walking and aging: A historical perspective

Walk on by_flickrThe evidence that exercise helps stave off mental decline in elderly people has been mounting for several years now, but an article by Wayne Curtis in The Atlantic today puts this research in perspective by looking back a century at Edward Payson Weston’s walk from San Francisco to New York in 1909, when Weston was 70.

Curtis notes that the field of gerontology, the study of aging, had been around for less than a decade at that point. Most scientists thought brain cells were not capable of regenerating – something we know today that they’re most definitely capable of – and doctors were of the mind that too-vigorous exercise could harm mental acuity. Popular reaction to Weston’s trek is documented through newspaper accounts of the day:

A column in the Dallas Morning News admitted that many considered Weston’s walk from ocean to ocean “foolishness” and “an idle waste of time.” But, the writer asked, was it “preferred to the needless senility into which far too many men begin to drift at the period of three score years and 10?”

Curtis eventually moves into recent decades and details some of the recent research into how moderate to vigorous walking can actually improve mental acuity in several populations, including Alzheimer’s patients:

The results [of one long-term study], published in the journal Neurology, were sweeping and conclusive: Those who walked the most cut in half their risk of developing memory problems. The optimal exercise for cognitive health benefits, the 
researchers concluded, was to walk six to nine miles each week. That’s a mile to a mile and a half a day, without walking on Sundays if you’re inclined to follow Weston’s example of resting on the Sabbath. (This study concluded that walking an additional mile didn’t help all that much.)

I have to admit I’m glad I live in this century and not in Weston’s time. I don’t think I have the fortitude he showed in bucking popular opinion – or, to be honest, in walking.

Previously: Even old brains can stay healthy, says Stanford neurologistExercise and your brain: Stanford research highlighted on NIH Director’s blog and The state of Alzheimer’s research: A conversation with Stanford neurologist Michael Greicius
Photo by  Stefano Corso

Health and Fitness, Nutrition, Pediatrics, Public Health

Pediatrics group issues new recommendations for building strong bones in kids

Pediatrics group issues new recommendations for building strong bones in kids

MilkshelfOur bones function as retirement-savings accounts for calcium: We deposit the mineral into our bones when we’re young, then draw on the stores as we age. Too little calcium in the “savings account” puts people at risk for osteoporosis and debilitating bone fractures later in life.

This means that, although osteoporosis is usually seen as a disease of old age, pediatricians and parents need to pay attention to bone health. This week, the American Academy of Pediatrics released updated guidelines for pediatricians on how nutrition and exercise can improve bone density in their patients. The guidelines were co-authored by Stanford’s Neville Golden, MD, who is also an adolescent medicine specialist at Lucile Packard Children’s Hospital Stanford. The report discusses calcium, which strengthens bones; vitamin D, which helps the body absorb calcium; and weight-bearing exercise, which promotes calcium deposition into the bones.

In addition to protecting against fractures in old age, the guidelines address the needs of kids whose bones are weakened by a variety of childhood and adolescent medical conditions, including juvenile osteoporosis, cystic fibrosis, lupus, celiac disease, cerebral palsy and anorexia nervosa.

A few highlights from the recommendations:

  • Children and adolescents should get their calcium mostly from food, not supplements. To meet calcium requirements, the committee recommends three or four daily servings of dairy foods (depending on the child’s age) and also suggests alternative food sources such as dark green veggies, beans, and calcium-fortified orange juice or breakfast cereals.
  • Vitamin D recommendations went up in 2011; the AAP agrees with the increased recommendations for all children and notes that kids using certain medications have even higher requirements than healthy children. Although the body can make vitamin D from sunlight, the report notes that kids are spending more time indoors and that sunscreen prevents vitamin D synthesis, making children more reliant on food and supplements to get enough vitamin D.
  • Soda often displaces milk in children’s diets, adding bone health to the list of reasons doctors should discourage soda consumption.
  • Weight-bearing exercise helps strengthen the bones. The report recommends activities such as walking, jogging, jumping and dancing over exercises such as swimming and cycling for building bone health.
  • Adolescent girls with eating disorders such as anorexia nervosa and the female athlete triad experience bone loss. In the past, some physicians have suggested that these young women could improve their bone density by taking oral contraceptives, but the report notes that randomized controlled trials have not found any evidence that oral contraceptives increase bone mass for these patients.

Previously: Goo inside bones provides structural support, study finds, New genetic regions associated with osteoporosis and bone fracture and Avoiding sun exposure may lead to vitamin D deficiency in Caucasians
Photo by Stephanie Booth

Cancer, Health and Fitness, Research

Exercise may boost effectiveness of chemotherapy

Exercise may boost effectiveness of chemotherapy

running_092214Staying physically active during chemotherapy treatment can benefit patients’ physical and mental health. But findings from an animal study show that exercising may also help reduce the size of tumors.

As reported by Futurity, University of Pennsylvania researcher Joseph Libonati, PhD, and colleagues originally set out to test whether adding a fitness regimen to chemotherapy would offset cardiac damage related to the drug doxorubicin. While the team failed to find any significant evidence that exercise provided protection against negative cardiac side-effects, they did find that mice that exercised while receiving chemotherapy had notably smaller tumors than those that had chemotherapy alone. From the article:

Further studies will investigate exactly how exercise enhances the effect of doxorubicin, but the researchers believe it could be in part because exercise increases blood flow to the tumor, bringing with it more of the drug in the bloodstream.

“If exercise helps in this way, you could potentially use a smaller dose of the drug and get fewer side effects,” Libonati says. Gaining a clearer understanding of the many ways that exercise affects various systems of the body could also pave the way for developing drugs that mimic the effects of exercise.

“People don’t take a drug and then sit down all day,” he says. “Something as simple as moving affects how drugs are metabolized. We’re only just beginning to understand the complexities.”

Previously: Stanford preventive-medicine expert: Lay off the meat, get out the sneaks, From leukemia survivor to top junior golfer, Examining exercise and cancer survivorship and Study shows benefits of exercise for patients with chronic health conditions
Photo by MilitaryHealth

Aging, Health and Fitness, Public Health, Research

Twenty-four percent of middle-aged and older Americans meet muscle-strengthening guidelines

Twenty-four percent of middle-aged and older Americans meet muscle-strengthening guidelines

free_weightsPast research has shown that strength training can benefit older adults’ health in numerous ways including arthritis relief, alleviating back pain, increasing bone density, improving sleep and boosting mental health. But despite these findings, a new study from Centers for Disease Control and Prevention (CDC) has found that few U.S. adults age 45 and older adhere to the Department of Health and Human Services’ muscle-strengthening recommendations.

The guidelines advise middle-aged and older adults to do moderate or high intensity muscle-strengthening activities that involve all major muscle group two or more days a week. Training can involve hand weights or weight machines, basic exercises such as sit-ups and push-ups or yoga and similar fitness practices.

In the latest study, researchers examined data from a telephone health survey conducted in 2011 by the CDC known as the U.S. Behavioral Risk Factor Surveillance System. For the survey, respondents provided information about the types of physical activities they engage in and frequency, as well as answered questions about if they specifically did exercises to strengthen their muscles. HealthDay reports:

Of all those who answered the questions on muscle strengthening, about 24 percent said they met the government’s recommendations.

Among those less likely than others to meet these guidelines were women, widows, those age 85 or older, people who were obese, and Hispanics. Participants who didn’t graduate from high school were also less likely to meet U.S. strength-training recommendations.

Jesse Vezina, of Arizona State University, and his fellow researchers concluded that interventions designed to encourage people to participate in strength training should target these high-risk groups.

Previously: Moderate exercise program for older adults reduces mobility disability, study shows, Help from a virtual friend goes a long way in boosting older adults’ physical activity and Do muscles retain memory of their former fitness?
Photo by Positively Fit

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