Sitting Risks; if more than 45 minutes at one sitting ...

Sit at 135 degree posture, spine weight spread evenly.

What are the risks of sitting too much?

Research has linked sitting for long periods of time with a number of health concerns, including obesity and metabolic syndrome — a cluster of conditions that includes increased blood pressure, high blood sugar, excess body fat around the waist and abnormal cholesterol levels. Too much sitting also seems to increase the risk of death from cardiovascular disease and cancer.

One study compared adults who spent less than two hours a day in front of the TV or other screen-based entertainment with those who logged more than four hours a day of recreational screen time. Those with greater screen time had:

• A nearly 50 percent increased risk of death from any cause
• About a 125 percent increased risk of events associated with cardiovascular disease, such as chest pain (angina) or heart attack

The increased risk was separate from other traditional risk factors for cardiovascular disease, such as smoking or high blood pressure.
Sitting in front of the TV isn't the only concern. Any extended sitting — such as behind a desk at work or behind the wheel — can be harmful. What's more, spending a few hours a week at the gym or otherwise engaged in moderate or vigorous activity doesn't seem to significantly offset the risk.
The solution seems to be less sitting and more moving overall. You might start by simply standing rather than sitting whenever you have the chance or think about ways to walk while you work. For example:

• Stand while talking on the phone or eating lunch.
• If you work at a desk for long periods of time, try a standing desk — or improvise with a high table or counter.
• Walk laps with your colleagues rather than gathering in a conference room for meetings.
• Position your work surface above a treadmill — with a computer screen and keyboard on a stand or a specialized treadmill-ready vertical desk — so that you can be in motion throughout the day.

The impact of movement — even leisurely movement — can be profound. For starters, you'll burn more calories. This might lead to weight loss and increased energy. Even better, the muscle activity needed for standing and other movement seems to trigger important processes related to the breakdown of fats and sugars within the body. When you sit, these processes stall — and your health risks increase. When you're standing or actively moving, you kick the processes back into action.

Don’t just sit there!

We know sitting too much is bad, and most of us intuitively feel a little guilty for a long TV binge. But what exactly goes wrong in our bodies when we park ourselves for nearly eight hours per day, the average for an adult? Many things, say four experts, who detailed a chain of problems from head to toe.

Organ damage

Heart disease

Muscles burn less fat and blood flows more sluggishly during a long sit, allowing fatty acids to more easily clog the heart. Prolonged sitting has been linked to high blood pressure and elevated cholesterol, and people with the most sedentary time are more than twice as likely to have cardiovascular disease than those with the least.

Over productive pancreas

The pancreas produces insulin, a hormone that carries glucose to cells for energy. But cells in idle muscles don't respond as readily to insulin, so the pancreas produces more and more, which can lead to diabetes and other diseases. A 2011 study found a decline in insulin response after just one day of prolonged sitting.

Colon cancer

Studies have linked sitting to a greater risk for colon, breast and endometrial cancers. The reason is unclear, but one theory is that excess insulin encourages cell growth. Another is that regular movement boosts natural antioxidants that kill cell-damaging
— and potentially cancer-causing — free radicals.

Muscle degeneration

Mushy abs

When you stand, move or even sit up straight, abdominal muscles keep you upright. But when you slump in a chair, they go unused. Tight back muscles and wimpy abs form a posture-wrecking alliance that can exaggerate the spine's natural arch, a condition called hyperlordosis, or swayback.

Tight hips 

   Flexible hips help keep you balanced, but chronic sitters so rarely extend the hip flexor muscles in front that they become short and tight, limiting range of motion and stride length. Studies have found that decreased hip mobility is a main reason elderly people tend to fall.

Limp glutes

Sitting requires your glutes to do absolutely nothing, and they get used to it. Soft glutes hurt your stability, your ability to push off and your ability to maintain a powerful stride.

Leg disorders

Poor circulation in legs

Sitting for long periods of time slows blood circulation, which causes fluid to pool in the legs. Problems range from swollen ankles and varicose veins to dangerous blood clots called deep vein thrombosis (DVT).

Soft bones

Weight-bearing activities such as walking and running stimulate hip and lower-body bones to grow thicker, denser and stronger. Scientists partially attribute the recent surge in cases of osteoporosis to lack of activity.

Mortality of sitting

People who watched the most TV in an 8.5-year study had a 61 percent greater risk of dying than those who watched less than one hour per day.

Hours of TV per day:

1-2 (4% risk of dying);

3-4 (14% risk of dying);

5-6 (31% risk of dying);

7++ (61% risk of dying).

Trouble at the top

 Foggy brain

Moving muscles pump fresh blood and oxygen through the brain and trigger the release of all sorts of brain- and mood-enhancing chemicals. When we are sedentary for a long time, everything slows, including brain function.

Strained neck

If most of your sitting occurs at a desk at work, craning your neck forward toward a keyboard or tilting your head to cradle a phone while typing can strain the cervical vertebrae and lead to permanent imbalances.

Proper
vertebrae
alignment

Sore shoulders and back

The neck doesn't slouch alone. Slumping forward overextends shoulder and back muscles as well, particularly the trapezius, which connects the neck and shoulders.

Bad back

Inflexible spine

When we move, soft discs between vertebrae expand and contract like sponges, soaking up fresh blood and nutrients. But when we sit for a long time, discs are squashed unevenly. Collagen hardens around tendons and ligaments.

Disk damage

People who sit more (than 45 minutes at one sitting) are at greater risk for herniated lumbar disks. A muscle called the psoas travels through the abdominal cavity and, when it tightens, pulls the upper lumbar spine forward. Upper-body weight rests entirely on the ischial tuberosity (sitting bones) instead of being distributed along the arch of the spine. Lumbar region bowed by shortened psoas .

So what can we do? The experts recommend . . .

Sitting on something wobbly such as an exercise ball or even a backless stool to force your core muscles to work. Sit up straight and keep your feet flat on the floor in front of you so they support about a quarter of your weight.

Stretching the hip flexors for three minutes per side once a day.

Walking during commercials when you're watching TV. Even a snail-like pace of 1 mph would burn twice the calories of sitting, and more vigorous exercise would be even better.

Alternating between sitting and standing at your work station. If you can't do that, stand up every half hour or so and walk.

 Trying yoga poses — the cow pose and the cat — to improve extension and flexion in your back. See pose diagram above.

The experts, Scientists interviewed for this report:

James A. Levine, inventor of the treadmill desk and director of Obesity Solutions at Mayo Clinic and Arizona State University.

Charles E. Matthews, National Cancer Institute investigator and author of several studies on sedentary behavior.

Jay Dicharry, director of the REP Biomechanics Lab in Bend, Ore., and author of "Anatomy for Runners." 

Tal Amasay, biomechanist at Barry University's Department of Sport and Exercise Sciences.

I'm surprised that the article doesn't discuss the impact of sitting w/ large muscle groups of thighs, glutes and lower back flexed thus using lots of blood oxygen and nutrients and producing lots of carbon dioxide and the impact of this on the human brain considering human brains use 50% of oxygen and nutrients in the blood simply to maintain homeostasis.   A working hypothesis I've come to from my own experiences, especially in last four years, of having everything taken from me in Morehead City, Carteret County, North Carolina, Washington, DC; Temple Hills, Prince Georges County, Maryland and Alexandria, Virginia, by gov't officals, mostly police seated in squad cars enforcing non-existent laws, laws not based on data or simply not following the law, is that sitting is causing our human brains not to get enough oxygen and nutrients and too much carbon dioxide thus producing lots of fearful/negative thinking....  Just thoughts but seems they could be easily tested to collect "data." Future experiments could be set up to test the "null" hypothesis that sitting doesn't have an effect on blood oxygen, nutrients and carbon dioxide levels. Ironically, those who do research for $$ don't typically test the "null" hypothesis of whatever it is their "promoting." Not unlike, James A. Levine, who's invented a treadmill that he's selling or anyone else who's paid $$ for their "research." 

Statistics about "How sitting is causing fatality, mortality and dreadful diseases from countries like USA, UK, Australia, Canada and other.

Unfortunately, the list doesn’t stop there..
But we can act now and overcome our sedentary life by staying active.

1. WHO - World Health OrganizationTaking everything into account, the World Health Organization reports that being physically inactive comes in fourth as a leading risk factor for death. The WHO report also mentioned that” Inactivity was found to be the main cause of about a quarter of breast and colon cancers, 27 percent of diabetes cases, and 30 percent of heart disease cases.”Source - World Health Organization.

2. Too Much SittingEven when adults meet physical activity guidelines, sitting for prolonged periods can compromise metabolic health. TV time and objective-measurement studies show deleterious associations, and breaking up sedentary time is beneficial. Sitting time, TV time, and time sitting in automobiles increase premature mortality risk. Further evidence from prospective studies, intervention trials, and population-based behavioral studies is required.Source - US National Library of Medicine

3. Why sitting too much is bad for your healthOne of the largest pieces of research to date on the subject - involving almost 800,000 people - found that, compared with those who sat the least, people who sat the longest had a:
• 112% increase in risk of diabetes
• 147% increase in cardiovascular events
• 90% increase in death caused by cardiovascular events
• 49% increase in death from any cause  Source - National health Science, UK

4. How Desk Jobs Ruin Your HealthThis grim conclusion may surprise you, but 18 studies reported during the past 16 years, covering 800,000 people overall, back it up. Several studies show that “Americans sit for most of their waking hours, 13 hours every day on average”.

5. Too Much Sitting: Health Risks of Sedentary Behaviour and Opportunities for ChangeToo much sitting is now recognised as a prevalent health Rapid advances in the science of sedentary behaviour are beginning to influence public health and occupational health thinking and have potentially important clinical implications.Source - Presidents Council on Fitness, Sports and Nutrition

7. Sitting increases your risk of getting cancer in a very big way
Based on a study of more than 220,000 residents in New South Wales, researchers found that the longer you spend sitting down every day, the higher the risk of dying prematurely, even if you engage in regular daily exercise. The study, published in the Archives of Internal Medicine, found that adults who sat for more than 11 hours a day had a 40 percent increased risk of dying within 3 years- from any cause- compared with those who sat for less than 4 hours a day.

The American Institute for Cancer Research held its annual conference early in 2012 and highlighted at that conference were specific research findings showing that 49,000 cases of breast cancer and 43,000 cases of colon cancer in the U.S. could be linked to inactivity.Source - The American Institute for Cancer Research

8. Sitting for prolonged periods increases risk of death, disease: studyProlonged time spent sitting and being sedentary is associated with an increased risk for heart disease, cancer and death, regardless of physical activity, according to a new study.

The meta-analysis review, published Monday in the Annals of Internal Medicine, examined 47 different studies that looked at sedentary behaviour and a range of negative health outcomes
.
The review found that prolonged periods spent sitting was associated with a greater risk for all-cause mortality, heart disease incidence and death, cancer incidence and death, and Type 2 diabetes in adults.Source - CTV National News Canada

9. The Truth About “The Truth About Sitting Down”How Sitting Wrecks Your Body?
As soon as you sit:
• Electric activity in the leg muscles shuts off
• Calorie burning drops to 1 per minute
• Enzymes that help break down fat drop 90%
After 2 hours: Good cholesterol drops20%
After 24 hours: Insulin effectiveness drops24% and risk of diabetes rises
Source -  The Research Headlines

10. Australian Workplace and SittingThe average Australian worker spends almost 33 hours per week at the workplace. Those working full time in jobs that involve ‘mostly sitting’ spend on average 6.3 hours per day sitting at work.

Many Australians are sitting longer than they are sleeping - sitting longer than 8hrs a day can increase risk of early death by 15%- focus on breaking up long periods into shorter periods by getting up and moving"

While most of the evidence to date relates to the health effects of overall sedentary behaviour, a high proportion of workers are exposed to prolonged sitting at work and there is a growing amount of evidence on adverse health effects associated with sedentary work.  Sedentary work may occur in both office-based occupations as well as other occupations which may have less scope for changed postures, such as call centre staff, crane operators and truck drivers.Source - Safe Work Australia

11.The News on Sitting Down; You May Want to Stand UpHumans weren't designed to sit all day. As such, sitting for long periods is a serious occupational health and safety problem. When your daily routine includes sitting for extended periods, the muscles in your legs that normally help pump blood aren't used much and as a result, blood can flow backwards in leg veins and pool, causing varicose veins and blood clots.Source - Canadian Centre For Occupational Health and Safety

12. Australians spend one month a year sitting watching TVAustralian adults spend on average four hours per day doing sedentary leisure activities such as watching television compared with only half an hour of physical activity, according to data released by the Australian Bureau of Statistics today.
Dr Paul Jelfs, from the Australian Bureau of Statistics, said the 2011-12 data reveals a tendency for high levels of sedentary behaviour across the adult population.Source - Australian Health Survey

Statistics about "How sitting is causing fatality, mortality and dreadful diseases from countries like USA, UK, Australia, Canada and other.

1. Taking everything into account, the World Health Organization reports that being physically inactive comes in fourth as a leading risk factor for death. The WHO report also mentioned that” Inactivity was found to be the main cause of about a quarter of breast and colon cancers, 27 percent of diabetes cases, and 30 percent of heart disease cases.Source - World Health Organization

2. Too Much Sitting
Even when adults meet physical activity guidelines, sitting for prolonged periods can compromise metabolic health. TV time and objective-measurement studies show deleterious associations, and breaking up sedentary time is beneficial. Sitting time, TV time, and time sitting in automobiles increase premature mortality risk. Further evidence from prospective studies, intervention trials, and population-based behavioral studies is required.Source - US National Library of Medicine

3. Why sitting too much is bad for your healthOne of the largest pieces of research to date on the subject - involving almost 800,000 people - found that, compared with those who sat the least, people who sat the longest had a:
• 112% increase in risk of diabetes
• 147% increase in cardiovascular events
• 90% increase in death caused by cardiovascular events
• 49% increase in death from any cause  Source - National health Science, UK

9. Australian Workplace and SittingThe average Australian worker spends almost 33 hours per week at the workplace. Those working full time in jobs that involve ‘mostly sitting’ spend on average 6.3 hours per day sitting at work.

Many Australians are sitting longer than they are sleeping - sitting longer than 8hrs a day can increase risk of early death by 15% - focus on breaking up long periods into shorter periods by getting up and moving"

While most of the evidence to date relates to the health effects of overall sedentary behaviour, a high proportion of workers are exposed to prolonged sitting at work and there is a growing amount of evidence on adverse health effects associated with sedentary
work. 
Sedentary work may occur in both office-based occupations as well as other occupations which may have less scope for changed postures, such as call centre staff, crane operators and truck drivers.Source - Safe Work Australia10.The News on Sitting Down; You May Want to Stand UpHumans weren't designed to sit all day. As such, sitting for long periods is a serious occupational health and safety problem. When your daily routine includes sitting for extended periods, the muscles in your legs that normally help pump blood aren't used much and as a result, blood can flow backwards in leg veins and pool, causing varicose veins and blood clots.Source - Canadian Centre For Occupational Health and Safety11. Australians spend one month a year sitting watching TVAustralian adults spend on average four hours per day doing sedentary leisure activities such as watching television compared with only half an hour of physical activity, according to data released by the Australian Bureau of Statistics today.
Dr Paul Jelfs, from the Australian Bureau of Statistics, said the 2011-12 data reveals a tendency for high levels of sedentary behaviour across the adult population.Source - Australian Health Survey

Unfortunately, the list doesn’t stop there..
But we can act now and overcome our sedentary life by staying active.

13. Impact of sitting and television viewing on life expectancy in the USA The estimated gains in life expectancy in the US population were 2.00 years for reducing excessive sitting to <3 1.38="" a="" and="" br="" day.="" day="" excessive="" from="" gain="" h="" of="" reducing="" television="" to="" viewing="" years="">

In 2010, for example, the journal Circulation published an investigation following 8,800 adults for seven years. Those who sat for more than four hours a day while watching television had a 46 percent increase in deaths from any cause when compared with
people who sat in front of the tube for less than two hours. Other researchers have found that sitting for more than half the day, approximately, doubles the risk of diabetes and cardiovascular problems.

Overall, when you combine all causes of death and compare any group of sitters with those who are more active, sitters have a 50 percent greater likelihood of dying.

Source - Killer chairs

3. Americans are increasingly becoming inactive and risking their health.
More Americans Lived A Sedentary Lifestyle In 2014; Number Of Physically Active Hits Lowest In 6 Years
Americans reduced their physical activity in 2014, despite the exploding popularity of wearable fitness trackers and apps, marked by a burgeoning market offering countless options.
On Wednesday, the Physical Activity Council (PAC) released its 2015 Participation Report, which found that 82.7 million Americans, or 28.3 percent, matched the council's definition of physically inactive last year.

Lose Weight With VIBRATIONS?

Machines like this one which vibrate your body while you stand on it or exercise on it have been touted by gyms as fat-busters. Doctors give their take on their effectiveness and warn that long-term use may lead to nerve and organ damage

Yes, vibration works to help you lose fat and weight – but only if you exercise and follow a sensible diet as well.

The vibration plate machine, which has a platform that vibrates while the person stands on it, has been making its presence felt in workout studios and even homes here.

Since one brand called Power Plate was first sold here six years ago, the number of dedicated Power Plate studios here has grown to six, while that of gyms that stock these machines has risen to 10, said its sole distributor Positive Impact.

It has also sold more than 300 such machines to individuals. Each costs between $5,000 and $23,000, depending on the size of the machine.

Health and wellness retail company Oto has also developed a machine based on whole body vibration. A spokesman said it has sold 25,000 units of the FLABeLOS, at $1,198 each, to individuals here since 2007.

The Power Plate studios combine pilates, kickboxing and core, stretch, toning and cardiovascular exercises with the vibration plate machine. Classes cost between $25 per group session and $90 for a one-to-one session. Each session typically lasts 40 to 45 minutes.

The principle behind this is something called “acceleration training”, in which you need a shorter amount of time to burn the same amount of calories.

Exercising on a vibration plate may also have positive effects on strength, stability and bone density, said doctors and Power Plate master trainer Tay Koon Hua.

This can be helpful for, say, those who have been injured. Exercise on the vibration plate is low-impact and lets them build up their injured muscles or joints, they added.

So far, at least two recent studies have shown that it does lead to increased fat loss.

But there are caveats. Furthermore, no long-term studies on the safety of whole body vibration exercise beyond eight months have been done yet.

BUILDING MUSCLE MASS

Medical and physiotherapy experts interviewed said standing on a vibration plate subjects the body to many small vibrations per second.

This causes the small muscles in the whole body to contract more and the tendons and ligaments to stretch more than when a person is standing on stable ground. This is because the body has to adjust constantly to the motion.

This helps build up muscle mass, strength and flexibility, said the medical experts.

Muscle cells burn more calories than other cells because they are responsible for all movements, including subtle ones such as blinking.

So the increased muscle mass will help the body to burn more calories, leading to the loss of fat.

Dr Daniel Wai, director of the obesity and metabolic unit at Singapore General Hospital, said: “The actual amount of calories burnt after one hour of such exercise (on a vibrating plate) is only around 100calories, but as muscles are built up, it helps increase the amount of energy we burn in the resting state.”

Dr Roger Tian, consultant sports physician and deputy medical director at the Singapore Sports Medicine Centre, said exercising on an unstable platform, such as the vibration plate, increases muscle use as the body tries to maintain stability.

This additional muscle use increases expenditure of calories.

Mr Tay, 39, a former physical education teacher who owns a dedicated Power Plate studio and has shares in Positive Impact, said the machine will increase exercise intensity in two ways.

It helps the body to use more than 90 per cent of its muscles. It also increases the gravitational force by two to six times when a person works out on it. Hence, it will be more difficult for a person to perform exercises on the plate than on the ground.

He said: “As more energy is needed to perform the same exercise, more calories are burnt on the vibrating plate.”

For these reasons, more body fat is lost when whole body vibration training is added to a diet or exercise regimen than either programme on its own or together, two studies have shown.

Both studies – one in Belgium and the other in the United States – were done by doctors and published in peer-reviewed journals.

In the Belgian study on 79 overweight patients published last year, doctors looked at the effect of long-term whole body vibration training on visceral fat.

Visceral fat is the fat surrounding the organs in the abdomen. Abdominal fat is made up of visceral fat and subcutaneous fat, which lies between the skin and the abdominal wall.

The patients were randomly divided into four groups. The first group received a low-calorie diet only, the second dieted and did traditional fitness training, including cardiovascular and weight exercises, the third dieted and followed a progressive Power Plate machine training programme, while the fourth was the control group.

After six months, the group which dieted and followed a Power Plate fitness regimen showed the largest percentage drop in body weight and in visceral fat.

Those in the diet and traditional fitness groups showed a slightly smaller decrease in both measurements, while the control group had no significant change.

In measurements taken at the end of the year-long study, after all participants had returned to their usual lifestyle, the group which exercised on the Power Plate machines was found to have maintained the amount of fat loss. However, the diet and fitness groups had reverted to their initial fat level.

The results were similar in the US study on 55 post-menopausal women, published in 2009. It compared the effects of no exercise, resistance training only and resistance training with whole body vibration.

At the end of eight months, the women who did not exercise gained 1.8 per cent of body fat, while those who did only resistance training lost 1.6 per cent and those who did both types of exercise lost 3 per cent.

RISK OF INTERNAL INJURY

The same effect of burning more calories can be achieved without a vibration plate, said Dr Tian. A person can simply increase the duration or speed of his workout, he said.

Ms Loy Yijun, a senior physiotherapist at National University Hospital’s centre for obesity management and surgery, said whole body vibration therapy alone would probably not lead to weight loss.

Her view is that vibration therapy aims to elicit a similar or superior response to resistance exercises by stimulating muscle reflexes and contractions.

Even if more fat is lost, a person’s cardiovascular fitness may not be significantly improved.

The limitation primarily arises from the lack of a cardiovascular workout, which is essential to burning calories, she said.

Moreover, it is important to realise that vibration plate exercise may result in potential harmful effects, doctors said.

Adjunct Associate Professor Hee Hwan Tak, an orthopaedic surgeon at Singapore Medical Group, said: “This exercise should be done with caution in the elderly or those with balance issues, for fear of falls.”

Soft tissues and body organs could be harmed by long-term vibration. For example, workers using vibration tools such as road drills can suffer from nerve damage to the hands due to chronic vibration. This is called “vibration white finger” disease.

It is not known if long-term use of vibration plate machines will create similar problems.

Dr Wai said: “We do not have studies that last longer than eight months, so do keep in mind that long-term safety is unclear.”


Evaluation of Human Response under
Vibration Condition
Hon Keung Yau, Bing Lam Luk, Sum Sang Chan

Abstract - The purpose of this study is to
investigate the human response under different
vibration frequencies. A total of nine
frequencies (1.6, 2.0, 2.5, 3.15, 4.0, 5.0, 6.3, 8.0
and 10.0Hz) were chosen as stimuli for testing in
the experiment. In this experiment, two tests
were conducted: Comparative Test and Feet Supporting
Test. Ten males and ten females were invited to
participate in the experiment. The major
findings revealed that (i) the uncomfortable
feeling increases with an increase of vibration
frequency, (ii) the feet support does have better
influence to the feeling of comfort for females
than males.

Index Terms – comparative test, human
response, supporting test, vibration

Manuscript received November 15, 2011.
H. K. Yau is with the Department of Systems Engineering and
Engineering Management, City University of Hong Kong, Kowloon
Tong, Kowloon, Hong Kong (corresponding author to provide phone:
852-34426158, Fax: 852-34420173. 

B. L. Luk is with the Department of Mechanical and
Biomedical Engineering, City University of Hong Kong,
Kowloon Tong, Kowloon, Hong Kong.

S. S. Chan was with the Department of Mechanical
and Biomedical Engineering, City University of Hong
Kong, Kowloon Tong, Kowloon, Hong Kong .

I. INTRODUCTION
In Hong Kong, most people take the public
transport to various destinations like schools and
offices every day. Common vibrations we can
experience come mainly from the uneven road,
changing of speed, sound produced when a sudden
stop of the bus and train, etc, and these vibrations
can cause damages to us. Different vibrations can
cause different levels of uncomfortable feeling on
males and females. Some past studies have
investigated how vibration affected working
efficiency, safety and health [5]. However, few
studies investigated the gender differences, if any,
in the human response under different vibration
frequencies. Therefore, we fill this research gap in
this study.

II. LITERATURE REVIEW
Vibration interferes with people’s working
efficiency, safety and health [5]. It also causes
discomfort, fatigue and physical pain [3]. Our
health are affected if the strength of vibration is
too large or the duration of vibration is too long
[1]. Past research results showed that feeling of
discomfort increases when the frequency increases
[8]. 5Hz is the resonance frequency for whole-body vibration.
It was also shown that the spine, inner organs and muscle are in
resonance when vibration frequency reaches 8Hz [6], [7]. The
feeling of discomfort increases even higher when more than one
organ of our body are in resonance. The thigh’s stiffness

can only affect little on the feeling of discomfort during vibration [7] while the tensed posture can increase
our stiffness and decrease the feeling of discomfort [4]. In
addition, the posture of tensed upper body
increases the stiffness of body so as to
increase the resonance frequency [2]. Due to
the resonance of spine and inner organs, the
uncomfortable index increases rapidly [6].
Besides, the uncomfortable feeling is much
worse than the relax pose or even cause
damage to our back if the vibration strength
reaches the resonance frequency [3].
III. RESEARCH METHOD
A. Participants
Twenty people (10 males and 10 females)
were invited to participate in the experiment.
They were of average age 21.95 years,
168.1cm tall and 59.1kg weight.
B. Design of experiment
To acquire the data, the following two tests were
conducted:
(i) Comparative test
(ii) Feet supporting test
(i) Comparative Test
 Method of magnitude estimation
1. To take the stimulus of 5Hz as a reference
2. Try other stimuli
3. Give an uncomfortable index comparing with the
reference stimulus
(ii)Feet Supporting Test
 Method of magnitude estimation
1. Try stimulus without feet support/upper body
relax as a reference stimulus
2. Try the same stimulus with feet support/ upper
body tensed
3. Give uncomfortable index comparing to the
reference stimulus
C. Experiment procedure
For the comparative test, participants were
tested under different vibration frequencies to
analyse discomfort effect at different frequencies.
If the test did not mention about the posture, then
the posture was assumed as upper body relax
without feet support. As many literatures pointed
out that 5Hz was the first starting resonance
frequency, a comparative test referencing at 5Hz
was carried out. Firstly, the participants were
asked to take a stimulus of 5Hz for 4 seconds and a
random selected frequency for another 4 seconds.
After the testing of the two stimuli, participants
were asked to fill in an uncomfortable index survey
as 100 was the mark for 5Hz. For example, if the
participant felt that the selected frequency caused
half uncomfortable feeling compared to that at 5Hz,
then he/she should fill in 50. If they think the
uncomfortable feeling is twice, they should fill in
200. Through the test, we could see whether there
were any differences between the male and
female’s responses at the same vibration level.
For the feet supporting test, participants were
exposed under all vibration frequencies with feet
support for 30 seconds. After that, they were asked
to fill in the uncomfortable index survey.
The test and frequency sequence was
randomized and counterbalanced across trials but
each pair of males and females was under the same
sequence for the analysis of difference in males
and females.

IV. RESULTS AND DISCUSSIONS

(a) Comparative test

Table I: Results of Comparative test
Frequency Index combination

Index male

Index female

1.6Hz 32.25 43 21.5
2.0Hz 39 48 30
2.5Hz 42.75 52 33.5
3.15Hz 62.5 70 55
4Hz 80 82.5 77.5
6.3Hz 117.25 119 115.5
8Hz 144.5 144 145
10Hz 184.5 183 186 

From the Table I, the correlation between
uncomfortable index and frequency for male
and female participants are 0.999 and 0.998,
respectively. Feeling of discomfort basically
increased when the frequency increased. This
finding is consistent with the results of Subashi
et al. [8]. Feelings of both males and females were similar
after the resonance frequency 5Hz. The feeling of
discomfort started to increase obviously at 5Hz. That
may be due to the appearance of resonance since 5Hz
which was mentioned by many researchers as the
resonance frequency for whole-body vibration [6], [7]. As
the resonance frequency will make participants feel more
uncomfortable than other frequencies, the feeling may
become similar for both males and females. There is a
large difference for the response of male respondents than
females for all frequencies except 10Hz. Besides, the
difference between males and females in response became
smaller after 5Hz, we can estimate that the vibration
strength may be too large to make both male and female
feel very uncomfortable, so that the response of males and
females are similar after 5Hz. Therefore, it can be
concluded that the resonance made the response in males
and females become similar after 5Hz. At 8Hz and 10Hz,
the uncomfortable feeling increased rapidly, the
uncomfortable index for 10Hz was almost twice of 5Hz.
That may be due to the resonance of our organs. The spine,
inner organs and muscle was in resonance when the
frequency reached 8Hz [6]. If more than one organ of our
body were in resonance, the feeling of discomfort
increased even higher.

(b) Feet Supporting Test

Table II: Results of feet support test

Frequency Index combination

Index male

Index female

1.6Hz 97.5 95 100
2.0Hz 96.5 98 95
2.5Hz 88.5 92 85
3.15Hz 89.25 90 88.5
4Hz 81.5 87 76
5Hz 80.75 84 77.5
6.3Hz 79 84 74
8Hz 72 82 62
10Hz 74.5 88 61

From the results (Table II), we noted that the
feet support does have better influence to the
feeling of comfort for females than males. The
correlation coefficients for males and females are
0.708 and 0.994 respectively. The uncomfortable
index keeps on decreasing when the frequency
increases up to 5Hz for females. This indicates that
the feet support can help to reduce the feeling of
discomfort. We also noted that the uncomfortable
index for females is lower at almost all frequencies
in the condition of using feet support. That may be
due to the difference in strength of buttock for
male and female. Besides, the feet support can decrease
the feeling of discomfort. As mentioned by some
researchers [7], the thigh’s stiffness will affect little
on the feeling of discomfort during vibration. Instead,
tensed posture can increase our stiffness and decrease the
feeling of uncomfortable [4]. Therefore, the difference
in response between male and female becomes
more obvious after 5Hz. Also, the variation of
uncomfortable index at the same frequency is quite
similar for both male and female as shown from the
table 2. The difference in response between males
and females become most significant at 8Hz and
10Hz. The figure shows a significant difference
between male and female at 8Hz and 10Hz. The
uncomfortable index keeps on decreasing but rising
at 10Hz for males, it may be due to the resonance
in organs as mentioned from the comparative test
[6]. But the feet support test is not suitable for all
people as some participants claimed that the feet
support will make them feel more uncomfortable at
some frequencies.

V. CONCLUSION
A series of human factors experiments
concerning the human response under different
vibration conditions was conducted in this study. It
was concluded that the uncomfortable feeling
increased with the increase of vibration frequency.
The difference in response for males and females is 
not significant after 5Hz. Also, the feet
support was more useful for females than
males. It seemed that feet support provided
more help to females than males especially at
8Hz and 10Hz. It may be due to the difference
in strength of buttock because the feet support
increased the loading of the buttock.

REFERENCES
[1] C.M. Byung, C.C. Soon and J.P. Se., “Automatic responses
of young passengers contingent to the speed and driving
model of a vehicle,” Int J Ind Ergon Vol. 29, pp. 187-198,
2002.

[2] Y. Huang, and M.J. Griffin, “Effect of voluntary periodic
muscular activity on nonlinearity in the apparent mass of the
seated human body during vertical random whole-body
vibration,” Journal of Sound and Vibration Vol. 298, pp. 824-
840, 2006.

[3] J.Z. Liu, M. Kubo, and H. Aoki, “A study on the difference
of human sensation evaluation to whole body vibration in
sitting and lying postures,” Appl Hum Sci, Vol. 14, pp. 219 –
226, 1995.

[4] Y. Matsumoto, and M.J. Griffin, “Non-linear characteristics
in the dynamic responses of seated subjects exposed to
vertical whole-body vibration,” Journal of Biomechanical
Engineering Vol. 124, pp. 527-532, 2002.

[5] R.W. Mcleod, and M.J. Griffin, “Mechanical vibration
included interference with manual control performance,”
Ergonomics Vol. 38, pp. 1431-1444, 1995.

[6] Mester, Spitzepfeil, and Yue., “Vibration Loads: Potential for
strength and Power development”, 2003

[7] N. Nawayseh and M.J. Griffin, “Non-linear dual-axis
biodynamic response to vertical whole-body vibration,”
Journal of Sound and Vibration Vol. 268, pp. 503–523, 2002.

[8] G.H.M.J. Subashia, and N. Nawaysehb, Y. Matsumotoa, and
M.J. Griffin, (2008). “Nonlinear subjective and dynamic
responses of seated subjects exposed to horizontal wholebody
vibration,” Journal of Sound and Vibration Vol. 321,
pp. 416–434, 2008 .

Doctor’s Politics Affect Your Care

Doctor’s Politics Affect Your Care



I already know that this newsletter is going to upset many people--especially those who don't read beyond the title. Everyone likes to believe that their political views are carefully thought out, rational opinions formed by their awareness of the world around them and a mastery of facts. In other words, they are the result of absolute free will and are therefore entirely independent of all other aspects of their lives. Anything that challenges that opinion, which is effectively a challenge to free will, and especially anything that contains the words Republican and Democrat, really upsets people. In other words, anything that even implies that our politics might be influenced by our fundamental psychological or even genetic makeup or, even worse, that our political proclivities might shape how we view the world and the decisions we make, is going to bring out the dogs of war.

But if we are honest about it, we all intuitively know that political beliefs do indeed spill over into nonpolitical domains such as consumer spending, choice of romantic partner, and job hiring. That said, what we're going to talk about today is something quite different but nevertheless touches on the same hot buttons. A new study suggests that the political beliefs of our primary care physicians may predict their professional decisions--at least for certain health questions.1 According to the study, when it comes to politicized health issues like marijuana and abortion, it turns out that a physician's partisan identity is highly correlated with his/her treatment decisions. Because physicians regularly interact with patients on politically sensitive health issues, and because the medical profession is increasingly politicized (e.g., state governments are regulating politicized aspects of medicine), it is necessary to understand how your doctor's political worldviews might impact their decisions, recommendations, and actions in the medical examination room when it comes to your diagnosis and treatment. That understanding should then inform not only how you filter their recommendations but also whether or not it's in your best interest to look for a new doctor.

The political beliefs of our primary care physicians may predict their professional decisions.

So, setting aside the question of free will for the moment, which really isn't being called into question by this study, let me suggest that you read through to the end of the article as there are real lessons to be learned from the several studies we're going to talk about--real lessons that can affect the health care you receive.

With that in mind, let's take a look at the newly released study in question.


Republicans, Democrats, and Doctors

The co-authors of the study, Eitan Hersh, an assistant professor of political science, and Matthew N. Goldenberg, MD, an assistant professor of psychiatry, linked the records of over 20,000 primary care physicians in 29 US states to a voter registration database, thus obtaining the physicians' political party affiliations. They then contacted 1,529 of them to participate in the study, ending up with a sample of 231 doctors--both Democratic and Republican primary care physicians--whom they then surveyed. The survey involved the physicians evaluating nine patient vignettes which they were told were recounted by patients as part of a complete physical. Three of the vignettes addressed especially politicized health issues (marijuana, abortion, and firearm storage). Specifically, the vignettes presented scenarios such as a healthy-appearing 38-year-old male patient who "acknowledges using recreational marijuana three times per week" or "who is a parent with two small children at home" and "acknowledges having several firearms at home." And yet another fictional patient said she had two abortions in the past five years. Those vignettes were interspersed with some more neutral complaints like obesity, depression, or not wearing a motorcycle helmet.

Hersh and Goldenberg then asked the physicians to rate the seriousness of the issue presented in each vignette and how they would treat the patient. The physicians who responded did not know that the survey was about their politics. Rather, they thought it was about how they administer the patient interviews that primary-care doctors give patients before they first treat them. On the politicized health issues--and only on such issues--Democratic and Republican physicians differed substantially in their expressed concern and their recommended treatment plan. (It should be noted that the study controlled for physician demographics like age, gender, and religiosity, patient population, and geography.)

According to Hersh and Goldenberg, "The evidence suggests that doctors allow their political views to influence their professional decisions in the medical exam room. Just as patients choose physicians of a certain gender to feel more comfortable, our study suggests they may want to make a similar calculation based on their doctor's political views." It's important to note that this is not an insignificant issue as physicians frequently interact with patients about politically salient health issues, such as drug use, firearm safety, and sexual behavior.


Perhaps not too surprisingly, Republican physicians expressed more concern than their Democratic colleagues about the vignettes on marijuana use and abortion whereas the Democratic physicians were more concerned about the vignette related to firearms. Democratic doctors were less likely to discuss the health risks of marijuana or highlight its legal risks or encourage the patient to cut down their usage.  On the other hand, they were more likely to urge patients not to store firearms in the home, whereas the Republican physicians were much more likely to discuss the health and legal risks of marijuana and to advise the patient to cut back. They also were twice as likely as Democrats to discourage patients from having more abortions in the future and 35 percent more likely to discuss mental health in connection with abortions. Interestingly, Republican physicians were also significantly more likely to ask their patients if they were storing their firearms safely, though Democrats were more likely to urge them simply not to have them in the home. It should be noted that research shows that counseling by doctors can help promote safe gun storage. On the other hand, studies show that a majority of doctors choose not to go there. Again, physicians of both parties similarly rated the vignettes on non-political issues like depression, alcohol abuse, obesity, and not wearing a motorcycle helmet.



Effect of "Republican" on seriousness of issue. (PNAS)

The study concluded that physician partisan bias can lead to unwarranted variation in patient care. Thus, awareness of how a physician's political attitudes might affect patient care is important to both physicians and patients alike. As Goldenberg noted, "Given the politicization of certain health issues affecting countless patients, it is imperative that physicians consider how their political views may affect their professional judgments. The evidence calls for heightened awareness among physicians and more training concerning our biases in how we address politically salient health issues." As the authors write in the study, "To be clear, we cannot say with any certainty what the root cause of partisan differences in treatment is. However, regardless of the underlying mechanism that affects physician judgment, the evidence suggests a clear effect from the patient's perspective."

In summary, "Just as a patient may seek out a physician of a certain gender to feel more comfortable, the evidence suggests that a patient may need to make the same calculation regarding political ideology." Of course, a Republican or Democratic doctor would likely live in an area where the majority of his or her patients were of the same party. Still, if a contentious health issue is discussed during an appointment, it might be the provider's political beliefs talking, rather than their medical training. In certain cases, according to the study's authors, it might be worth getting a second opinion--perhaps a few towns over.

That said, although I would tend to agree with the study's observations, I'm not sure I agree with their recommendation, at least as stated. But before we go there, let's take a look at the elephant in the room. (And yes, the pun was deliberate.)

The Elephant in the Room

Hersh said he hopes the study will open up a dialogue about how political bias affects medical decision-making and make practitioners more aware of ways in which their personal beliefs might affect the care they give patients. Depending on the study's response, he says, he might even consider making his data on physician names and party affiliations public. This would be important because until the political data can be effectively linked to actual outcomes, the true extent of how politics affect physicians' decisions won't be clear. Unfortunately, he is likely to encounter resistance, especially among the large number of doctors who don't think that their political views inform their practice decisions. As Rep. Phil Roe (R-Tenn.), a retired obstetrician-gynecologist who co-chairs the GOP Doctors Caucus,4 told the Washington Post, "I never once treated a Republican or Democrat cancer in my life. When a patient walked into my office, I didn't know if they were a Republican or a Democrat, and I honestly didn't care."5 Roe went on to tell the Post that he hopes patients will seek out the best care available regardless of their doctor's political affiliation. "Party affiliation should have nothing to do with patient care."

And he is correct. Party affiliation should have nothing to do with patient care. Unfortunately, his pronouncements on the study have nothing to do with the study's actual conclusions. They are a red herring. In fact, the study has nothing to do with Republican or Democratic cancer. All the study is saying is that certain mindsets that are frequently, but not exclusively, associated with party affiliation do have an effect on physician decision making.

In fact, other research has shown that this is even more ingrained than you might think--that there is frequently a genetic factor to political leanings. A study, conducted by researchers out of the University of California, San Diego and Harvard University, identified a particular gene that seems to predispose certain people to a more "liberal" outlook.6 (We will talk more about what a "liberal" outlook actually means in a moment.) Data from more than 2,500 volunteers in the National Longitudinal Study of Adolescent Health was analyzed to compare people with the R7 variant of the DRD4 gene.7 Keep in mind that a person's political bent has always been assumed to be a product of their environment and social background, not their genes. And while environment and background certainly have a large impact on each person's beliefs, this study strongly indicates there is something going on behind the scenes in our DNA that influences us right down to our core values. Research has established that approximately 38% of us possess the R7 variant of the DRD4 gene. And please keep in mind that scientists hasten to add that neither version of the gene is better than the other -- if one were superior, natural selection most likely would have eliminated the inferior form.





Now let's talk about what we mean by "liberal," at least as far as this study is concerned. In fact, "liberal" in this case does not refer to which candidate you vote for but, rather, refers to a penchant for novelty seeking behavior. Earlier studies have determined a link between the R7 variant and novelty-seeking behavior. People with the variant may be more likely to try new experiences and take some risks. In other words, the study is saying that those who are more likely to be comfortable pushing boundaries and trying new things can be defined as liberal. And those who don't, who like to play it safe, can be defined as conservative. And again, neither is superior when it comes to genetic survival. On the one hand, playing it safe could have certainly been advantageous to prehistoric man if wild animals were about. But being willing to try new things and push out into new territory would have been advantageous if food supplies were strained in your familiar environment. Each tendency can be advantageous depending on the circumstances.

In any case, now researchers are applying the new findings to this information and suggesting that when people with the R7 gene variant have also had an active social network, they may be more likely to seek out their friends' opinions on political subjects and be open to a wider range of lifestyles, creating a more liberal position politically. And that's the tie-in to politics. However, having the variant does not guarantee a final resting point on the political spectrum. For example, if either the variant form of the gene is not there or the adolescent years were not socially popular ones, then the person can fall anywhere on the political spectrum. The findings were the same across age, gender, ethnicity, and background differences. The bottom line is that we're only talking about tendencies here. There are indeed conservative Democrats and liberal Republicans (I believe they're called RINO's...Laughing). Again, we're not really talking about politics. We're talking about a fundamental, psychological way of viewing the world that merely gives people a predilection to end up in one party or another--not a guarantee.

In fact, more than half a century of research in genetics, neuroscience, and psychology has demonstrated that human behaviors, including social and political attitudes, are influenced by genetic and neurobiological factors. However, these findings have not been widely accepted or incorporated into the dominant paradigms that explain the underlying causes of political ideology. This has been attributed in part to measurement and sample limitations, as well the relative absence of molecular genetic studies.

In addition, there's the 2012 study that combined evidence from over 12,000 twins pairs, ascertained from nine different studies conducted in five democracies with the data from three genome-wide association studies on political ideology.8 In other words, it was not a small study. It concluded that political ideology constitutes a fundamental aspect of one's genetically informed psychological disposition.

So what does this mean for doctors? Well, let's return to Rep. Roe's statement: "When a patient walked into my office, I didn't know if they were a Republican or a Democrat, and I honestly didn't care." We should now be able to see that this statement is irrelevant. We're not actually talking about party affiliation. We're talking about genetically informed psychological dispositions that can inform how doctors choose to treat certain conditions--not that they differentiate between Republican and Democratic patients. And yes, people of certain dispositions tend to gravitate to certain political parties that support that disposition--but again, that's only a tendency, not a certainty. In any case, those same psychological dispositions tend to lean doctors towards conclusions and treatments in line with that disposition.

But What Does the Mean to Me?

At this point, let's just throw politics completely out the window, which should simplify the discussion and remove the emotional heat from it. Let's just acknowledge that different doctors will vary in:

What treatment options they recommend in certain situations
Where they fall on the risk vs safety continuum
Now things become much simpler, which allows us to establish some physician selection guidelines.

Surgery

When it comes to surgery, there are essentially two kinds: standard and cutting edge, high risk.

For standard surgical procedures, you probably want a conservative doctor who follows the safest protocols available. When it comes to routine surgery, you don't want a risk taker.
For more cutting edge or experimental surgeries, you probably want a surgeon who is comfortable playing in unfamiliar territory. If the surgical technique involved is not routine, you want a doctor who thrives when playing outside their comfort zone.
And by all means, check out your surgeon's rating for the particular procedure you're looking to have them perform. Why in the world would you choose a doctor to operate on you who isn't very good at performing the operation and tends to leave lots of bodies on the operating table? And for that matter, be sure and check out the safety score for the hospital where your surgeon is going to be performing the procedure. They provide your doctor's support team.

Primary Care Treatment

On the other hand, when it comes to general medical diagnosis and treatment, you probably want a doctor who lines up with your view of health and nutrition.

>If you're into herbs and alternative health, find a doctor who is friendly (or at least not hostile) to those protocols. Why would you want to put yourself in a position where you're constantly fighting with your doctor about the medications he/she prescribes or the supplements you want to take?

>If you're a strong believer in the virtues of toeing the medical line, then track down the most medically astute doctor you can find--regardless of their opinion of alternative health.

>If you smoke marijuana or use birth control, find a doctor who doesn't fight you about it or look askance at your lifestyle.

>If you don't believe in antidepressants or any other class of pharmaceutical drugs, then don't go to a doctor who refuses to explore alternative treatments--even alternative medical treatments--with you.


>And, as with surgeons, even when selecting a primary care physician, it's a good idea to check out how the doctors you're looking at rate with previous patients.

If you find that you are with the wrong doctor, don’t hesitate to change physicians. It's your life, not your doctor's.


The bottom line is that when medical skill is the priority, find the most skillful doctor you can find--regardless of political outlook. When looking for a primary care physician who will work with you on an ongoing basis, find a doctor of like mind and similar disposition. And if you find that you are with the wrong doctor, don't hesitate to change physicians. Remember, it's your life, not your doctor's.