Are Cross-Country Skiers Premier Athletes?

 

Cross Country Skiing Couple

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With winter upon us, it is a good reminder that cold weather is not an excuse for inactivity. Athletes from cold-weather climates, such as the Nordic countries, are not content to stay indoors during winter. In fact, cross-country skiers from these colder climates might be considered the premier human aerobic athletes.

Although some picture cross-country skiing as slowly shuffling along at a leisurely pace, the reality of competition is much different. For example, the winner of the 50 km (31 miles) freestyle at the 2014 Winter Olympics finished the race in less than one hour and 47 minutes. That’s longer than a marathon but finished in less time. And these races typically go uphill for 50 percent of the time!

Physiologically, skiing is interesting from many perspectives. The biomechanics of skiing are interesting because the arm and leg movements must be coordinated to efficiently move forward. The whole-body nature of skiing makes the physiology fascinating to study. Cross-country skiing puts large demands on the heart to deliver blood and oxygen to exercising muscle. This challenge is greater than for running or cycling (which engages only the legs) because both the arms and the legs need to work with skiing.

The amount of blood going to the arms versus the legs constantly changes, too. These changes are based on the hundreds of technique transitions needed to cross the varying terrain during a race. The great physical endurance required improves the ability of cross-country skiers’ muscles to use oxygen. These athletes have some of the highest levels of oxygen consumption (VO2max) on record. Legendary physiologist Bengt Saltin and other researchers have used the unique whole-body nature of cross-country skiing to study blood flow delivery. This approach has provided us great insight into the regulation of blood flow in both athletes and non-athletes.

Cross-country skiers demonstrate that cold weather is not an excuse to be sedentary, but rather an excuse to be great.

 

Ben Miller Benjamin Miller, PhD, is an associate professor in the department of Health and Exercise Science at Colorado State University. He co-directs the Translational Research in Aging and Chronic Disease (TRACD) Laboratory with Karyn Hamilton, PhD.

How Your Brain Decides to Keep Your New Year’s Resolutions (or Not)

 

New Year goals or resolutions

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ispy-physiology-100th-post-imageThe start of a new year can feel like a fresh slate or an unwritten book. It’s a chance for many of us to resolve to do things better (eating, exercising) or to stop doing certain things altogether (smoking). But most people don’t succeed in sticking to their resolutions in the long term, and the reason might surprise you. It’s not always a question of lacking willpower or being lazy. Keeping resolutions makes your brain work hard, and that mental effort takes time and practice.

Researchers from the University of Minnesota found that your brain uses more than one decision-making system to build and regulate habit-forming and goal-directed behaviors. One system looks at the steps you take to make a decision. Another evaluates your actions and decides when you need to change a new behavior in order to receive a reward.

Here’s where the hard work comes in: The researchers explain that goal-directed behavior requires mental energy and planning. You have to plan ahead before making decisions to know how to reach your goal. Let’s say, for example, you’re trying to cut back on sweets and are invited to a party. If you want to enjoy a dessert at the party but don’t want to completely ignore your resolution, you’ll need to plan to eat less sugar during the rest of the day. Over time, as you keep making more goal-oriented decisions, the choices become more automatic.

Another study suggests that nerve cells stick together when you form a habit that you’ve enjoyed (such as eating dessert after dinner). The strong bond they create can be tough to break, and—like getting up early to go running or sticking to that diet—it isn’t always easy. This is especially the case when your emotions take over and you feel resentful or angry at the challenging changes you’re trying to make. Being mindful and keeping your emotions out of the decision-making process can help. Your brain, like your body, just needs time to adjust to your new routines.

Good luck and happy new year.

Erica Roth

2016’s Ten Most Read Posts

It’s been a physiology-full 2016 on the I Spy Physiology blog! From exercise to respiration to heart health and beyond, we’ve explored how the bodies of humans and other animals work, adapt and react. Today, we take a look back at our 10 most read posts of the year.

Concussions among football players was headline news in 2016. Against this backdrop, our most popular post of the year looked at how woodpeckers can bang their heads roughly 12,000 times a day at a greater force than the average football hit without sustaining a head injury. Posts about the amazing endurance of Iditarod sled dogs and a researcher’s excellent explanation of what physiology is and why it’s important round out the top three. Check out this year’s top 10:

If you’ve got a topic that you’d like us to cover in 2017, we’d love to hear from you! Share your thoughts in the comments or send us an email.

Stacy Brooks

Bring on Winter! (But Stay Safe and Healthy)

 

girl playing on a winter walk

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Winter officially begins next week with the winter solstice—the day of the year with the fewest hours of sunlight—on Dec. 21. With the cold weather and shorter days, you might be tempted to curl up under a blanket until the spring thaw. Whether you plan to hibernate or get outside to enjoy the chill, we’ve got some good reads about how our physiology responds to the cold weather.

Check out these throwback posts featuring cold weather tips to help you stay safe and healthy during the coldest months:

Have fun, be safe and take note of how your body adapts to the season!

Stacy Brooks and Erica Roth

 

 

Exercise: It does a body—no, your brain—good!

Brain

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It’s 7:30 a.m., I’m looking for my keys, grabbing my bag and herding everyone out of the door as we hurry off to school and work. Wait! One more trip back into the house for the forgotten homework assignment, a lunchbox and … it seems I have forgotten several things. Is it stress, lack of sleep or just the natural aging process? Regardless, it seems I need a memory-boosting workout.

Exercise is no longer just for affecting the size of your muscles, but also the size of your brain. As we age, the volume of our brain naturally decreases. However, in people at risk for Alzheimer’s disease, one of the numerous cognitive diseases under the dementia umbrella, there is a more marked decrease in brain volume. Being physically active has been shown to slow or even stop the decrease in brain volume in older people, even among those at risk for Alzheimer’s disease.

The Physical Activity Guidelines for Americans issued by the U.S. Department for Health and Human Services state that adults should get 150 minutes of moderate-intensity activity—such as walking, running, swimming and cycling—each week to promote and maintain health. These and other forms of moderate-intensity exercise have also been positively linked to maintenance of memory and learning as we age.

According to a recent study in the research journal Alzheimer’s and Dementia, reaching recommended physical activity goals has substantial effects on brain volume. Ninety-one adults ranging from ages 50 to 74 wore an accelerometer, a device which records and measures the wearer’s steps and speed of movement, for seven days. Subjects who performed physical activity for 150 minutes or more per week had temporal lobe sections that were 5–6 percent larger than their sedentary counterparts. The temporal lobe of the brain is associated with learning and memory. This sustained brain volume associated with physical activity was noted among people with a family history of Alzheimer’s disease, those who have the Alzheimer’s associated gene and those who were not at high risk.

The moral of the story? Get up and move. Your brain will remember to thank you.

 

Jessica Taylor updated 6-1-2016 Jessica C. Taylor, PhD, is an assistant professor of physiology in the College of Osteopathic Medicine at William Carey University in Hattiesburg, Miss.

Can Alcohol Cause Irregular Heartbeat?

red wine

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Alcohol and heart health have a complicated relationship. Recent research suggests that moderate drinking may reduce your risk of stroke. But for some people, even one or two drinks a day may increase the risk of a form of heart disease called atrial fibrillation (AFib).

AFib is an irregular heartbeat of the two upper chambers of the heart (atria). During an episode of AFib, the atria beat quickly and out of synch with the lower chambers of the heart (ventricles). This irregular pattern can cause blood to clot in the heart, which also increases the risk of stroke.

A recent study published in the Journal of the American Heart Association suggests that over time, moderate alcohol consumption may cause the left atrium to become larger. The enlargement of the heart chamber can lead to AFib in some cases. This is one of the first studies to show in a large population of humans that structural changes in the heart can cause AFib. Previously, AFib had been thought to arise as a result of problems with the electrical impulses in the heart.

For most people who follow a heart-healthy diet, exercise and don’t have high cholesterol or high blood pressure, the occasional drink probably won’t hurt or lead to AFib. However, it’s a good idea to be aware of the alcohol-related heart disease risk as office parties and family gatherings get into full swing this holiday season.

Learn more about atrial fibrillation from the Mayo Clinic.

Erica Roth

Handling the Pain of Acid Reflux at Holiday Time

Acid reflux

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With Thanksgiving coming up, eating—of all things rich, indulgent and delicious—is top of mind for many Americans. But for people with gastroesophageal reflux disease (GERD), eating this type of food often and in large quantities can be a challenge. This week is GERD Awareness Week, a good time to learn how to prevent GERD symptoms and still enjoy your holiday season.

GERD is the return of stomach contents, including acid, into the esophagus, sometimes known as acid reflux. More than 60 million people in the U.S. experience GERD symptoms, such as frequent heartburn, at least once a month.

You may have a higher risk of having GERD if you:

  • produce a lot of gastric acid
  • have a hiatal hernia
  • have a weak lower esophageal sphincter (the ring of muscle between the esophagus and stomach)
  • are obese
  • smoke
  • drink alcohol or a lot of caffeine

Women have additional risk factors, including being a young adult and adopting a stooping or slouching posture. Certain foods, including peppermint, chocolate, fatty or fried foods, and acidic fruits, also raise the risk of developing heartburn and acid reflux.

Simple dietary and lifestyle changes can be effective for many people to reduce the frequency and intensity of GERD symptoms, including:

  • losing weight if needed
  • quitting smoking
  • eating small meals throughout the day
  • avoiding foods that cause symptoms
  • waiting at least two hours before lying down after a meal

Another first line of treatment is medication, such as antacids or proton pump inhibitors. These drugs are available over the counter and by prescription from your doctor and reduce or stop the production of stomach acid to prevent symptoms.

If occasional heartburn bothers you after a big meal, try making lifestyle changes to help you feel better. If your symptoms persist, your doctor may look deeper into the possible causes for your discomfort. Knowing the risk factors for GERD can help you avoid complications and stay healthy throughout the holidays and all year long.

To learn more about GERD, visit the National Institute of Diabetes and Digestive and Kidney Diseases website

 

layla-al-nakkashLayla Al-Nakkash, PhD, is a professor in the Department of Physiology, at Midwestern University, Glendale, Ariz. She is the course director for medical physiology for medical and podiatry students. Her area of research relates to understanding how intestinal dysfunction (in diseases such as cystic fibrosis and diabetes) can be ameliorated by changes in diet.

Nanoparticles: A High-Tech Solution for Lung Cancer Treatment

No smoking badge

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Lung cancer is the leading cause of cancer-related death for both men and women in the U.S., according to the American Cancer Society (ACS). Responsible for 1 in 4 cancer deaths, there were approximately 224,390 new cases and 158,000 lung cancer deaths in 2016 alone.

Despite the seemingly grim outlook for lung cancer patients, many people diagnosed with the disease are cured. The key for these positive outcomes is early cancer detection and treatment. A number of new and innovative therapies have been developed that have contributed greatly to the prolonged survival of patients. However, as the statistics show, there is still a vital need for better treatment options to further improve survival rates.

A main focus in cancer research has been to target the cell communication that causes normal cells to change into cancerous cells. Our understanding of these processes has grown significantly during the past decade, and scientists have been able to point to a number of proteins that are involved in this transformation. Recently, a group of scientists combined its knowledge of these cellular processes with a high-tech anti-cancer drug delivery method to wipe out lung cancer cells. They used nanoparticles with a drug that specifically targeted a protein known to be involved in this cell-changing process. Nanoparticles are very tiny particles between 1 and 100 nanometers—about 1,000 times smaller than a cell—that are made of special material depending on their use. Here, they used a special type of nanoparticle that allowed the drug to get into the lung cancer cells.

In addition to new therapies to fight cancer, there are low-tech ways you can reduce your cancer risk. One of the main causes of lung cancer is smoking tobacco products. The No. 1 way to stay healthy is to avoid tobacco, including smokeless tobacco products, which can also cause cancer. Tomorrow, November 17, is the Great American Smokeout—a good day to make a commitment to quit. ACS has a number of stop-smoking resources available on its website. Additionally, eating healthy and staying active will reduce your risk for cancer-related illness.

audrey-vasauskasAudrey A. Vasauskas, PhD, is an assistant professor of physiology at the Alabama College of Osteopathic Medicine.

The Proof Is in the Papers: APS’s Long History with the Nobel Prize

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2016 Nobel Prize in Physiology or Medicine winner Yoshinori Ohsumi. Credit: ShuraRB Ufa/Flickr

Last month, Yoshinori Ohsumi of the Tokyo Institute of Technology was awarded the 2016 Nobel Prize in Physiology or Medicine. Dr. Ohsumi won for his research in autophagy, the mechanism that cells use to break themselves down—an essential function in all cells.

The Nobel Prize, arguably the most prestigious award in the life sciences, was established by Alfred Nobel. A wealthy scientist and inventor, Nobel stipulated in his will that the Physiology or Medicine prize was to be awarded to researchers who “have conferred the greatest benefit on mankind” in the past year.

According to the Nobel website, this prize “is commonly referred to as the Nobel Prize in Medicine. The wording in Alfred Nobel’s will, however, is Physiology or Medicine. It is important to make this distinction since, in the days of Alfred Nobel, physiology was used to describe what is today a number of biological fields.” Indeed, many specialized fields of science and medicine—neuroscience, biochemistry, endocrinology, pharmacology and pathology to name a few—have their roots in physiology. For us at the American Physiological Society (APS), the inclusion of physiology underscores the fundamental importance of this area of research to so many scientific and medical advances that we benefit from today.

Since the first prize was awarded in 1901, 76 researchers who went on to win a Nobel have published their work in APS journals. Many of their discoveries explained how our bodies work, spurred new technologies and led to the development of treatments for diseases such as anemia, diabetes and cancer. Check out our Nobel Laureates page to learn more about these scientists, the research that won them the prize and the articles they published in the APS journals.

Stacy Brooks

Are You at Risk for Type 2 Diabetes?

Diabetes text with felt tip pen (Click for more)

During American Diabetes Month in November, you may notice more people are talking about diabetes, a disease that affects 29 million Americans. It’s a great time to learn more about diabetes and the ways that you can decrease or manage your risk of developing the disease.

Diabetes mellitus is a problem with how your body handles blood glucose (sugar). People who have type 2 diabetes aren’t able to use the hormone insulin properly to remove glucose from the bloodstream for use in the fat and muscle cells.  Ultimately, this causes people with type 2 diabetes to have higher than normal levels of glucose in their blood.

You may have heard that someone who is overweight and has a large, apple-shaped body is more likely to develop metabolic syndrome—a group of health conditions such as elevated blood pressure, blood sugar and cholesterol levels—which may increase the risk of developing diabetes.  However, there are a number of less well known risk factors for type 2 diabetes including:

Some research even links non-health-related factors such as job security to an increased diabetes risk. A recent study published in the Canadian Medical Association Journal  analyzed data from 19 different studies including almost 141,000 participants which suggested that job insecurity was associated with a modest increased risk of diabetes.  Job insecurity has also been associated with weight gain (a diabetes risk factor) and coronary artery disease (a complication of diabetes).

Recognizing risk factors for diabetes and dealing with them, if possible, is important for both children and adults. Consuming a healthy, nutrient-rich diet and staying physically active can help maintain weight, manage stress and avoid type 2 diabetes and its many related complications. To learn more about ways to prevent diabetes, visit the American Diabetes Association website.

barb-goodman

Barb Goodman, PhD, is a professor of physiology at the University of South Dakota.