Exercise Results in Larger Brain Size and Lowered Dementia Risk

 Newswise, August 3, 2016--

 RESEARCH ALERT

Exercise results in larger brain size and lowered dementia risk

FINDINGS
 — Using the landmark Framingham Heart Study to assess how physical activity affects the size of the brain and one’s risk for developing dementia, UCLA researchers found an association between low physical activity and a higher risk for dementia in older individuals. This suggests that regular physical activity for older adults could lead to higher brain volumes and a reduced risk for developing dementia.

The researchers found that physical activity particularly affected the size of the hippocampus, which is the part of the brain controlling short-term memory. Also, the protective effect of regular physical activity against dementia was strongest in people age 75 and older.

BACKGROUND
Though some previous studies have found an inverse relationship between levels of physical activity and cognitive decline, dementia and Alzheimer’s disease, others have failed to find such an association. The Framingham study was begun in 1948 primarily as a way to trace factors and characteristics leading to cardiovascular disease, but also examining dementia and other physiological conditions.

For this study, the UCLA researchers followed an older, community-based cohort from the Framingham study for more than a decade to examine the association between physical activity and the risk for incident dementia and subclinical brain MRI markers of dementia.

METHOD
The researchers assessed the physical activity indices for both the original Framingham cohort and their offspring who were age 60 and older. They examined the association between physical activity and risk of any form of dementia (regardless of the cause) and Alzheimer’s disease for 3,700 participants from both cohorts who were cognitively intact. They also examined the association between physical activity and brain MRI in about 2,000 participants from the offspring cohort.

IMPACT
What this all means: one is never too old to exercise for brain health and to stave off the risk for developing dementia.

Life Preserver: Exercise May Be the Simple Solution for Rescuing Seniors’ Lost and Injured Muscle

Newswise, July 22, 2016 — Exercise may have some surprising benefits for seniors who experience rapid muscle loss and muscle injury and loss as they age. Researchers at McMaster University have found that physical activity can help retain, even repair and regenerate damaged muscle in the elderly.

The findings challenge what is generally seen as an inevitable fact of life: that muscle atrophy and damage cannot be completely repaired in old age and in some cases lost altogether.

Researchers compared and analyzed the capacity for muscle repair performance ofin a group of young mice, a group of old sedentary mice and a group of old exercise-trained mice. three groups of young and old mice, some of which had experienced muscle injury, some of which had been exercise trained, and others which had not.

“The world’s older population is rapidly growing and preventing muscle loss and promoting muscle repair is paramount to preserve health,” says Gianni Parise, lead author of the study and an associate professor in the Department of Kinesiology at McMaster.

“These findings suggest that age-related compromised muscle repair can be rescued with regular exercise,” he says.

After eight weeks of exercise, researchers found the old mice were able to repair and rebuild muscle more quickly following injury when compared to the old mice which had not exercised.

And after a period of 28 days, muscle repair was comparable to that of young mice. Old mice that had not exercised did not fully recover.

The findings suggest that exercise can be used as a preventative measure in older adults who lose muscle rapidly when their activity levels fall, which can happen for a variety of reasons, including illness or extended hospital stays.

“Quite simply, this demonstrates the importance of remaining active throughout life,” says Parise. “Regular exercise can preserve basic processes that govern muscle health.” 

The research was published in the FASEB Journal.

Walking Faster or Longer Linked to Significant Cardiovascular Benefits in Older Adults

Newswise, November 23, 2015— In a large prospective community-based study of older Americans, modest physical activity was associated with a lower risk of cardiovascular disease (CVD). 

This was true even among men and women older than age 75 at baseline – a rapidly growing population for whom regular activity has been advised, but with little supportive empirical evidence.

Led by senior author, Dariush Mozaffarian, M.D., Dr.P.H., dean of the Friedman School of Nutrition Science and Policy at Tufts University, the researchers studied a group of American adults whose mean age was 73 at the start of the study and who were then followed for 10 years.

Information on various usual activities was assessed at baseline and regularly updated during follow-up. When the current study’s research team evaluated different aspects of physical activity by the men and women during this ten-year period -- a greater pace, walking distance, and leisure activity-- each was associated with a lower risk of cardiovascular disease.

The associations found include:

• After adjustment for other risk factors and lifestyle behaviors, those who were more active had significantly lower risk of future heart attacks and stroke.
• Adults who walked at a pace faster than three miles per hour (mph) had a 50%, 53%, 50% lower risk of coronary heart disease (CHD), stroke and total CVD, respectively, compared to those who walked at a pace of less than two mph.
• Those who walked an average of seven blocks per day or more had a 36%, 54% and 47% lower risk of CHD, stroke and total CVD, respectively, compared to those who walked up to five blocks per week.
• Those who engaged in leisure activities such as lawn-mowing, raking, gardening, swimming, biking and hiking, also had a lower risk of CHD, stroke and total CVD, compared to those who did not engage in leisure-time activities.
• The findings were similar in both men and women, in those above or below age 75 at baseline, and including only those with similarly good or excellent self-reported health.

The researchers studied 4,207 men and women who had been enrolled in the Cardiovascular Health Study (CHS). CHS is a National Heart, Lung, and Blood Institute of the National Institutes of Health-supported national cohort of U.S. men and women who were enrolled in 1989-90 from Medicare eligibility lists and whose health was followed over time.

The researchers used the information in the CHS database concerning physical activity, including walking, leisure-time activities and exercise intensity, and other health information coming from annual study visits such as physical exams, diagnostic testing, laboratory evaluations, personal health histories, and measured risk factors.

“Our study of older Americans shows that, even late in life, moderate physical activity such as walking is linked to lower incidence of cardiovascular disease,“ commented the first author Luisa Soares-Miranda, Ph.D., a member of the research team and currently a postdoctoral student with the Research Centre in Physical Activity, Health and Leisure, Faculty of Sport at the University of Porto, Portugal.

“It appears that whether one increases the total distance or the pace of walking, CVD risk is lowered. Fortunately, walking is an activity that many older adults can enjoy.”

“While national guidelines recommend that older adults engage in regular physical activity, surprisingly few studies have evaluated potential cardiovascular benefits after age 75, a rapidly growing age group,” said Mozaffarian.

 “Our findings confirm a beneficial relationship between walking and leisure activities and CVD late in life.

“These results are especially relevant because, with advancing age, the ability to perform vigorous types of activity often decreases. Our findings support the importance of continuing light to moderate exercise to improve health across the lifespan.”

Additional authors of this study are David F. Siscovick, M.D., M.P.H., senior vice president for research at the New York Academy of Medicine; Bruce M. Psaty, M.D., M.P.H., Ph.D., professor in the Departments of Medicine and Epidemiology at the University of Washington and a senior investigator in the Group Health Research Institute; and W.T. Longstreth, Jr., M.D., M.P.H, professor of neurology and adjunct professor of epidemiology in the Department of Neurology at the Harborview Medical Center at the University of Washington.

This research was supported by contracts from the U.S. Department of Health and Human Services: HHSN268201200036C and HHSN268200800007C; and awards from the National Heart, Lung, and Blood Institute of the National Institutes of Health: N01HC55222, N01HC85079, N01HC85080, N01HC85081, N01HC85082, N01HC85083, N01HC85086, and HL080295. Luisa Soares-Miranda is supported by a grant funded by the Portuguese Foundation for Science and Technology (FCT).

Soares-Miranda, Luisa; Siscovick, David S.; Psaty, Bruce M.; Longstreth, W.T. Jr.; and Mozaffarian, Dariush, “Physical Activity and Risk of Coronary Heart Disease and Stroke in Older Adults: The Cardiovascular Health Study.” Circulation (published online before print November 4, 2015) doi: 10.1161/CIRCULATIONAHA.115.018323

About the Friedman School of Nutrition Science and Policy
The Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University is the only independent school of nutrition in the United States.

The school's eight degree programs – which focus on questions relating to nutrition and chronic diseases, molecular nutrition, agriculture and sustainability, food security, humanitarian assistance, public health nutrition, and food policy and economics – are renowned for the application of scientific research to national and international policy.

Exchanging Physical Activity for Sitting Time Associated with Lower Risk of Death for Less-Active Older Adults

Newswise, October 1, 2015 — In this study, investigators measured the amount of time older adults spent sitting and in different physical activities.

 They next used statistical models to estimate risk of death associated with replacing one hour of sitting time with an equal amount of physical activity.

The investigators found that for less active older adults, replacing sitting time with exercise or other activities, like household chores or walking, resulted in lower risk of death.

In contrast, highly active older adults had to replace an hour of sitting with purposeful exercise to reduce risk of death.

Although the researchers cautioned that their results were from statistical models, not from actual changes in behavior, replacing sitting time with physical activity appears to provide important mortality benefits, particularly for less-active adults.

High-Intensity Training Delivers Results for Older Men—But Not for Older Women

 Newswise, September 14, 2015 — Tampa, Fla. (September 10, 2015)—High-intensity training (HIT) is often recommended as a way to improve cardiovascular fitness in men and women.

HIT exercise can have a positive effect on a person’s maximum oxygen consumption (VO2max) and mitochondrial oxidative phosphorylation (OXPHOS) capacity, the pathway that cells use to metabolize energy.

However, studies on these exercise regimens have focused on younger subjects. University of Copenhagen researchers set out to study whether the effects were the same for older males and females as those noted in younger adults.

They will present their results at the APS Conference "Physiological Bioenergetics: From Bench to Bedside" in Tampa.

The research team observed obese senior males and females 62 and older. The subjects were assigned a regimen of high-intensity exercise that occurred three times per week for six weeks. Each session included five one-minute bursts of exercise performed at 125 percent of VO2max.

OXPHOS was measured in the subjects’ muscle and abdominal fat, along with their VO2max, body composition and several other metabolic measurements before and after the exercise regimens were performed.

While males increased their VO2max and OXPHOS in the muscle and reduced their body fat percentage by the end of the six weeks, no changes were seen in females.

The researchers did note, however, that female OXPHOS capacity in abdominal fat was higher to begin with. They said that more analysis is needed to explain the gender differences in the results.

Steen Larsen, PhD, of the University of Copenhagen presented “High intensity training increases mitochondrial respiratory capacity in old males but not females” during a poster session on Thursday, Sept. 10, in the Harbour Island Ballroom of the Westin Tampa Harbour Island.

About the American Physiological Society
Physiology is the study of how molecules, cells, tissues and organs function in health and disease. Established in 1887, the American Physiological Society (APS) was the first U.S. society in the biomedical sciences field. The Society represents more than 11,000 members and publishes 14 peer-reviewed journals with a worldwide readership.

Surge in Bicycle Injuries to Riders Over 45

Cycling renaissance causing more hospitalizations in older adults

Newswise, September 2, 2015 — The incidence of bicycle accidents has increased significantly in the U.S. in recent years, with many serious injuries occurring among riders older than 45, according to a new study led by UC San Francisco.

The researchers used a national injury surveillance database to study trends in bicycle injuries from 1998 to 2013. They found that the rate of hospital admissions associated with bicycle injuries more than doubled during that timeframe, especially with head and torso injuries.

Altogether, the proportion of injuries occurring to riders above age 45 rose 81 percent, from 23 percent to 42 percent, the authors said, and similarly the proportion of hospital admissions to older riders increased 66 percent, from 39 percent to 65 percent.

The results are published in the September 1, 2015 edition of JAMA, the Journal of the American Medical Association.

“These injuries were not only bad enough to bring riders to the emergency room, but the patients had to be admitted for further care,” said senior author Benjamin Breyer, MD, MAS, associate professor of urology at UCSF and chief of urology at UCSF partner hospital San Francisco General Hospital and Trauma Center. 

“If you take typical 25-year-olds and 60-year-olds, if they have a similar crash, it’s more likely the older person will have more severe injuries.”

Urban cycling has become increasingly popular in recent years for both recreation and work, and this trend has occurred while the U.S. shifts to an older demographic.

In the new study, the researchers found that the percentage of injured cyclists with head injuries rose from 10 percent to 16 percent. Approximately two thirds of the total injuries occurred among men, the authors said, and there was “no significant change in sex ratio over time.”

“These injury trends likely reflect the trends in overall bicycle ridership in the United States in which multiple sources show an increase in ridership in adults older than 45 years,” the authors said. 

“Other possible factors … include an increase in street accidents and an increase in sport cycling associated with faster speeds.”

The authors say their findings highlight the need for more safe riding practices and better infrastructure to prevent cycling-related injuries.

“Bicycle riding provides a fantastic way to get exercise and it has a low impact on joints,” said Breyer. 

“Previous research has shown it has broad health benefits with reduced mortality. But on a national level, we need expanded support for improving the general infrastructure for cycling, especially bike lanes. 

"And all cyclists should be aware of the risks and take appropriate precautions such as using appropriate safety gear, including helmets, and they should follow the rules of the road.”

Data were derived from the National Electronic Injury Surveillance System.

Co-authors are Thomas Sanford, MD, a resident physician in urology; Charles McCulloch, PhD, a UCSF professor and vice chair of the department of epidemiology and biostatstics; Rachael Callcut, a UCSF assistant professor of surgery; and Peter R. Carroll, MD, MPH, chair of the UCSF Department of Urology and leader of the prostate cancer program at the UCSF Helen Diller Family Comprehensive Cancer Center.

Breyer is supported by grant K12DK083021 from the National Institute of Diabetes and Digestive and Kidney Diseases. Callcut is supported by grant 8KL2TR000143-09 from the National Institutes of Health.

About UCSF: UCSF is a leading university dedicated to transforming health worldwide through advanced biomedical research, graduate-level education in the life sciences and health professions, and excellence in patient care. 

Founded in 1864 as a medical college, UCSF now includes top-ranked graduate schools of dentistry, medicine, nursing and pharmacy; a graduate division with world-renowned programs in the biological sciences, a preeminent biomedical research enterprise and top-tier hospitals, UCSF Medical Center and UCSF Benioff Children's Hospitals. Please visit www.ucsf.edu/new

Manage AFib Risk for Better Health

September 1, 2015--(Family Features) Approximately 1.5 million American women live with atrial fibrillation, a heart disorder commonly known as “AFib” that can lead to deadly or life-impairing stroke. For an undiagnosed woman living with AFib, knowing symptoms and risk factors can help mitigate this serious health threat. Women living with AFib can also take steps to manage this condition and their risk for stroke.  

AFib is a heart rhythm disorder in which the atria – the two upper chambers of the heart – beat rapidly and irregularly. Women with AFib are more likely than men with AFib to have a stroke. And, after the age of 75, an overwhelming majority of people with AFib – 60 percent – are women.

Diagnosing the condition

Up to a third of women with AFib don't feel symptoms. Others feel tired and experience heart palpitations, which may feel like a fluttering or flopping sensation in the chest or the feeling that the heart is beating too quickly. A woman experiencing AFib may also feel dizzy or short of breath. Some feel chest pain or feel faint.

Certain health and lifestyle risk factors make women more susceptible to AFib. Along with age and an existing heart condition, high blood pressure and obesity are major risk factors. Women who drink more than 10 ounces of alcohol a day are also at risk. Other risk factors include diabetes, overactive thyroid, high blood pressure, sleep apnea, lung disease, smoking, caffeine and stress.

With or without elevated risk factors, a woman experiencing symptoms should schedule a consultation with a doctor to determine if these symptoms are caused by AFib.

Living with AFib

Women living with AFib can manage their condition and associated risk for stroke by adopting healthy lifestyle behaviors. Increasing physical activity, adopting a diet that is low in fat, sodium and cholesterol, avoiding alcohol, and moderating stress and blood pressure levels are all necessary to manage AFib and avoid more serious health problems. AFib patients should choose caffeine-free coffee and herbal tea over caffeinated drinks. Moderate exercise such as walking, biking, swimming, yoga and strength training, combined with good hydration, can significantly improve AFib symptoms and reduce stroke risk. 

Isolation is a common feeling for women living with AFib. Resources such as WomenHeart’s new Virtual Support Network can help address the need for education and emotional and psychosocial support for women living with AFib. The Network is free and open to all women living with AFib and their caregivers.

Learn more about WomenHeart’s free patient support services for women living with heart disease, including AFib, and register to receive free online heart health information at www.womenheart.org.

  

Optimal Exercise Regimen Could Aid Pulmonary Hypertension Patients

Newswise, August 27, 2015 — A physical therapy researcher with the IU School of Health and Rehabilitation Services at Indiana University-Purdue University Indianapolis has been awarded a $465,000 National Institutes of Health grant to optimize aerobic exercise training for patients with pulmonary arterial hypertension, a goal data suggests could reduce morbidity and mortality among those with the disease.

Traditionally, it had been thought that these patients, who often struggle to walk across a room or climb a flight of stairs, shouldn’t exercise, said Mary Beth Brown, an assistant professor in the Department of Physical Therapy.

“It’s only in the last decade that the first evidence came out that exercise may be okay and may even be beneficial”, Brown said. 

“Because it is such a relatively new potential therapy there is a lot of work that needs to be done to optimize it, just like with any other new therapy.”

Pulmonary hypertension is high blood pressure that occurs in the arteries in the lungs. Blood vessels that carry blood from the heart to the lungs become narrow, forcing the heart to work harder to pump the blood through.

As the pressure builds, the heart's right ventricle must work harder to pump blood through the lungs, eventually causing the heart muscle to weaken and eventually fail.

While researchers believe exercise is beneficial, the best approach to maximizing those benefits and minimizing risks has yet to be discovered, Brown said.

“Patients with pulmonary hypertension can get extremely high pulmonary pressures during exercise,” she said. “So you have to wonder what the implications of that are.”

One thing that happens with pulmonary hypertension is that tolerance for exercise, even walking short distances, worsens over time, Brown said. Researchers believe that is due in part to skeletal muscle and heart muscle metabolism failing to generate energy as efficiently as they had before the onset of the disease.

Regular exercise is expected to help with the exercise intolerance in pulmonary hypertension because exercise is known to reverse or at least ameliorate the inefficient energy metabolism of other diseases, Brown said.

“If we can find an exercise protocol that will improve blood pressure in the lungs, and thus the load on the right heart, in addition to promoting improvement in skeletal muscle and heart metabolism, we could actually slow the progression of the disease,” Brown said.

She has already tested, for the first time, in a rat model with a mild form of pulmonary hypertension, the use of high intensity interval training, which alternates short periods of intense exercise with less-intense recovery periods.

The results were startling, Brown said.

She found improvement in blood pressures in the lungs, not only during exercise but at rest as well. 

Further, the enlargement in the size of the right ventricle, caused by pulmonary hypertension, was reversed.

“We’ve never seen reversal of the right heart hypertrophy,” she said. “My first thought was this can’t be right, so the experiment was repeated, but we got the same results again.”

With the NIH grant, Brown will now conduct similar high intensity interval training using a rat model with a more severe form of pulmonary hypertension to see if there is as much or more benefit as occurred with a mild form of the disease.

She will employ implantable telemetry to measure pulmonary pressures during exercise in her rat model, over course of disease development and treatment, which has never been done.

“That’s important because patients don’t always have problems when they are just resting. They have them when they are walking across the room or going up a flight of stairs,” Brown said. 

“We need to understand the hemodynamics during physical exertion so we can better optimize exercise protocols.”

With findings from an earlier study that showed a drop in pulmonary pressures to normal levels for a period of time in animals that performed a single exercise session, Brown’s research will determine which exercise protocols give the best window of time of normalized pulmonary pressures, Brown said.

“That in itself could potentially produce a huge benefit,” Brown said. “Patients who exercised daily would have more of these post-exercise windows of lower pressure, and less load on the heart.”