Category Archives: Physiology

How Exercise Keep Us Young

4/18/2017: New York Times, see article here.

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Active older people resemble much younger people physiologically, according to a new study of the effects of exercise on aging. The findings suggest that many of our expectations about the inevitability of physical decline with advancing years may be incorrect and that how we age is, to a large degree, up to us. Aging remains a surprisingly mysterious process. A wealth of past scientific research has shown that many bodily and cellular processes change in undesirable ways as we grow older. But science has not been able to establish definitively whether such changes result primarily from the passage of time — in which case they are inevitable for anyone with birthdays — or result at least in part from lifestyle, meaning that they are mutable. This conundrum is particularly true in terms of inactivity. Older people tend to be quite sedentary nowadays, and being sedentary affects health, making it difficult to separate the effects of not moving from those of getting older.

In the new study, which was published this week in The Journal of Physiology, scientists at King’s College London and the University of Birmingham in England decided to use a different approach. They removed inactivity as a factor in their study of aging by looking at the health of older people who move quite a bit.  “We wanted to understand what happens to the functioning of our bodies as we get older if we take the best­case scenario,” said Stephen Harridge, senior author of the study and director of the Centre of Human and Aerospace Physiological Sciences at King’s College London. To accomplish that goal, the scientists recruited 85 men and 41 women aged between 55 and 79 who bicycle regularly. The volunteers were all serious recreational riders but not competitive athletes. The men had to be able to ride at least 62 miles in six and a half hours and the women 37 miles in five and a half hours, benchmarks typical of a high degree of fitness in older people. The scientists then ran each volunteer through a large array of physical and cognitive tests. The scientists determined each cyclist’s endurance capacity, muscular mass and strength, pedaling power, metabolic health, balance, memory function, bone density and reflexes. They also had the volunteers complete the so-called Timed Up and Go test, during which someone stands up from a chair without using his or her arms, briskly walks about 10 feet, turns, walks back and sits down again.

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The researchers compared the results of cyclists in the study against each other and also against standard benchmarks of supposedly normal aging. If a particular test’s numbers were similar among the cyclists of all ages, the researchers considered, then that measure would seem to be more dependent on activity than on age. As it turned out, the cyclists did not show their age. On almost all measures, their physical functioning remained fairly stable across the decades and was much closer to that of young adults than of people their age. As a group, even the oldest cyclists had younger people’s levels of balance, reflexes, metabolic health and memory ability. And their Timed Up and Go results were exemplary. Many older people require at least 7 seconds to complete the task, with those requiring 9 or 10 seconds considered to be on the cusp of frailty, Dr. Harridge said. But even the oldest cyclists in this study averaged barely 5 seconds for the walk, which is “well within the norm reported for healthy young adults,” the study authors write.

Some aspects of aging did, however, prove to be ineluctable. The oldest cyclists had less muscular power and mass than those in their 50s and early 60s and considerably lower overall aerobic capacities. Age does seem to reduce our endurance and strength to some extent, Dr. Harridge said, even if we exercise. But even so, both of those measures were higher among the oldest cyclists than would be considered average among people aged 70 or above. All in all, the numbers suggest that aging is simply different in the active. “If you gave this dataset to a clinician and asked him to predict the age” of one of the cyclists based on his or her test results, Dr. Harridge said, “it would be impossible.” On paper, they all look young. Of course, this study is based on a single snapshot of an unusual group of older adults, Dr. Harridge said. He and his colleagues plan to retest their volunteers in five and 10 years, which will provide better information about the ongoing effects of exercise on aging. But even in advance of those results, said Dr. Harridge, himself almost 50 and an avid cyclist, this study shows that “being physically active makes your body function on the inside more like a young person’s.”

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It’s good for every body!

 

A version of this article appears in print on 01/13/2015, on page D4 of the NewYork edition with the headline: A Prescription for Youth. © 2017 The New York Times Company

A Short Summary of Everything Science Knows On How To Slow Ageing

Ageing is related to metabolism

The authors of this study have identified 9 key aspects of ageing on your metabolism. Metabolism isn’t some organ or group of organs but it is a complete system created by the working of billions of cells inside our body. This system is responsible for converting the fuel or food we take into to energy so that our body can function.

With age, the metabolic process slows down. DNA gets damaged and this introduces errors and inefficiency is the entire workings of the cells. The process of destroying old and worn out cells (autophagy) also slows down and this failure has detrimental effect on our whole body. Our body experiences so much stress during the course of its life that it becomes difficult for it to perform well with age.

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Ageing cannot be stopped but it can be slowed down

If ageing is all about metabolism, then it wouldn’t be surprising for you that the food we eat has a lot of affect on the ageing process. It is suggested that a Mediterranean diet can help extend your life. So what exactly is a Mediterranean diet? It is a diet high in healthy fats like olive oil, vegetables, whole grains, fish etc. However, it involves very little amount of red meat and sugar. Apparently replacing proteins with complex carbohydrates is healthier for us and aids in a longer life.

It doesn’t end here. Calorie restriction is also necessary. Overeating is not to be done and studies also suggest that introducing periods of fasting in your diet is also beneficial for some people. And the last one should not be a surprise to us; regular exercise. This helps all nine aspects that were identified in the paper that cause ageing.

Our unhealthy Lifestyles are slowly killing us

Improvements in health facilities, sanitation etc may have aided in increasing the life span but there are still problems that exist. Diets that are high in sugar, unhealthy fats and red meat create a lot of stress for metabolism and makes it inefficient. This increases the chances of obesity.

As most of us know, America is a place that has been struck with the problem of obesity. Americans have failed to consume healthy diets and spend far too many hours in activities that do not allow a lot of movement. The problem is serious and the authors have tried to call the people to immediate action if they wish to live a healthier and a longer life.

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I liked this study as it brings together dozens of studies on ageing and combines them together to create a more knowledgeable source for us. Most of the researches that have been done in the past are mostly done on lab animals, whereas, only a fraction of these studies are based on human trials. This study combines various studies and tries to bring out a broader aspect to the previous unclear studies and now it can only be hoped that people recognize the importance of a healthy lifestyle after reading this paper.

Science Alert.  Full article here.

October in National Spinal Health Month – The basics of Posture

Posture is the way you hold your body while standing, sitting, or performing tasks like lifting, bending, pulling, or reaching. If your posture is good, the bones of the spine — the vertebrae — are correctly aligned.

4 steps toward good posture

You can improve your posture — and head off back pain — by practicing some imagery and a few easy exercises.

  • Imagery. Think of a straight line passing through your body from ceiling to floor (your ears, shoulders, hips, knees, and ankles should be even and line up vertically). Now imagine that a strong cord attached to your breastbone is pulling your chest and rib cage upward, making you taller. Try to hold your pelvis level — don’t allow the lower back to sway. Think of stretching your head toward the ceiling, increasing the space between your rib cage and pelvis. Picture yourself as a ballerina or ice skater rather than a soldier at attention.
  • Shoulder blade squeeze. Sit up straight in a chair with your hands resting on your thighs. Keep your shoulders down and your chin level. Slowly draw your shoulders back and squeeze your shoulder blades together. Hold for a count of five; relax. Repeat three or four times.
  • Upper-body stretch. Stand facing a corner with your arms raised, hands flat against the walls, elbows at shoulder height. Place one foot ahead of the other. Bending your forward knee, exhale as you lean your body toward the corner. Keep your back straight and your chest and head up. You should feel a nice stretch across your chest. Hold this position for 20-30 seconds. Relax.
  • Arm-across-chest stretch. Raise your right arm to shoulder level in front of you and bend the arm at the elbow, keeping the forearm parallel to the floor. Grasp the right elbow with your left hand and gently pull it across your chest so that you feel a stretch in the upper arm and shoulder on the right side. Hold for 20 seconds; relax both arms. Repeat to the other side. Repeat three times on each side.

Practice these imagery and posture exercises throughout the day. You might try to find a good trigger to help you remember, such as doing one or more of them when you get up from your desk, or right before scheduled breaks and lunch. Soon it will become a habit.

Adapted from Harvard Med School’s newsletter, HealthBeat

Active body, active mind

The secret to a younger brain may lie in exercising your body

It is widely recognized that our physical fitness is reflected in our mental fitness, especially as we get older. How does being physically fit affect our aging brains? Neuroimaging studies, in which the activity of different parts of the brain can be visualized, have provided some clues. Until now, however, no study has directly linked brain activation with both mental and physical performance.

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As reported in the latest volume of the journal NeuroImage, an exciting new study led by Dr Hideaki Soya from the University of Tsukuba in Japan and his colleagues show, for the first time, the direct relationship between brain activity, brain function and physical fitness in a group of older Japanese men. They found that the fitter men performed better mentally than the less fit men, by using parts of their brains in the same way as in their youth.

As we age, we use different parts of our brain compared to our younger selves. For example, when young, we mainly use the left side of our prefrontal cortex (PFC) for mental tasks involving short term memory, understanding the meaning of words and the ability to recognize previously encountered events, objects, or people. When older, we tend to use the equivalent parts of our PFC on the right side of the brain for these tasks. The PFC is located in the very front of the brain, just behind the forehead. It has roles in executive function, memory, intelligence, language and vision.

If you are an aging woman, you will be wondering if these results can be applied to your female brain. Both aging sexes might also wonder whether increasing aerobic fitness later in life can increase mental fitness. The results aren’t in, but I’m heading off for a brisk walk just in case.


Story Source:

The above post is reprinted from materials provided by University of Tsukuba. Note: Materials may be edited for content and length.


Journal Reference:

  1. Kazuki Hyodo, Ippeita Dan, Yasushi Kyutoku, Kazuya Suwabe, Kyeongho Byun, Genta Ochi, Morimasa Kato, Hideaki Soya. The association between aerobic fitness and cognitive function in older men mediated by frontal lateralization. NeuroImage, 2015; DOI:10.1016/j.neuroimage.2015.09.062
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METs for Formal Exercise

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METs for Sports and Leisure Activities

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The Body is Amazing!

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