Richard G. Petty, MD

Old But Sound Advice on Health

Henry Homes Lord Kames.jpg




“A rich man cannot enjoy a sound mind nor a sound body without exercise and abstinence; and yet these are truly the worst ingredients of poverty.”      

–Henry Home, Lord Kames (Scottish Judge and Philosopher, 1696-1782)

Resting Racehorses

Your humble reporter lives on a horse farm, and many of our equine friends compete on a regular basis, so we are always interested in anything to keep them fit, healthy and happy.

I was interested to see a report of some research done in Finland. The main carbohydrate store in muscle is called glycogen, and Seppo Hyyppä, from MTT Agrifood Research Finland, looked at the way in which muscle glycogen stores are rebuilt after exercise. This is an important question, and not only for horses: glycogen is the most important nutrient during exercise and if glycogen stores are depleted the horse breaks down the protein in its own muscles to provide energy. So if the horse is chronically over-exercised it can hurt him.

The two most important factors in rebuilding muscle glycogen were:

  • Sufficient recovery time between intense training periods, and
  • Hydration


Giving horses an isotonic glucose-electrolyte rehydration solution soon after exercise helps to overcome dehydration significantly better than providing them with plain water.

The research also showed that weighing the horse before and after exercise gave a reasonably accurate estimate of the rate at which glycogen was being replenished. If you don’t have a set of weighing scales handy, you can measure the horse’s chest circumference.

The research also confirmed what every horse owner knows: you can tell a lot by looking at a horse: his general alertness and, for example, suppleness and appetite, indicate that he is in good condition.

“A canter is the cure for every evil.”
–Benjamin Disraeli, 1st Earl of Beaconsfield (English Statesman, Novelist and, in 1868 and from 1874-1880, British Prime Minister, 1804-1881)

“A man on a horse is spiritually as well as physically bigger than a man on foot.”
–John Steinbeck (American Writer and, in 1962, Winner of the Nobel Prize in Literature, 1902-1968)

Stretching and Exercise

I think that most of us have been told that it is really important to stretch before we hit the gym, and do it again after we have finished. It is said to improve performance as well as reducing the risk of injury and post-exercise stiffness. It is one of those things that has just entered mass consciousness.

However a new study using the Cochrane database shows that stretching before or after exercise has little or no effect on muscle soreness between half a day and three days later.

Two researchers identified 10 relevant trials, each of which involved between 10 and 30 people. Nine of the studies had been carried out in laboratory situations and people stretched for everything from 40 seconds to 10 minutes.

The investigators used a 100-point scale to assess stiffness after exercise. The results showed that the effects of stretching were extremely small. Stretching reduced soreness by less than 1 point on the 100-point scale. The size of the effect was similar if stretching was performed before or after activity.

The authors point out that there is still a need to see whether stretching can have an effect on people in the community who have reduced levels of flexibility.

“A great man can bend and stretch.”
–Chinese proverb

“The simple exercise of stretching helps to counter the congestions, compressions, and adhesions which obstruct the flow of the vital force through the spinal column with its sixty-two branching nerves and thus to regain energy. This truth of the need of spine-loosening movement is instinctively known by every dog and cat, every lion and tiger, for they apply it immediately after awakening from sleep. The back, the legs, and even paws are bent and stretched and even rolled by them in this natural exercise.”
–Paul Brunton (a.k.a. Raphael Hurst, English Philosopher, Traveler, Spiritual Teacher and Author, 1898-1981)

“Dachshunds are ideal dogs for small children, as they are already stretched and pulled to such a length that the child cannot do much harm one way or the other.”
–Robert Benchley (American Writer, Actor and Critic, 1899-1945)

Exercise May Be the Best Anti-inflammatory

It is almost twenty years since I was awarded my research doctorate and some of what I said at the time was controversial: I made a lot about the link between inflammation, diabetes mellitus and cardiovascular disease. Now we know more, and the link is a lot less controversial.

A number of studies have suggested that regular exercise reduces inflammation but it is still not clear whether there is a definite link. And if there is a link, how does it work? One candidate that we have discussed before has been a link between the autonomic nervous system – sympathetic and parasympathetic – and inflammation. When we exercise, the sympathetic nervous system increases our heart rate and improves lung function, while the parasympathetic system helps to slow things down as we stop exercising.

A recent study by kinesiology and community health researchers at the University of Illinois provides evidence that may help explain some of the underlying biological mechanisms that take place as the result of regular exercise.

The objective of the research was to examine the independent effect of the “tone” in the parasympathetic nervous system by assessing heart rate recovery after exercise, and whether there was a link between heart rate recovery and circulating levels of C-reactive protein (CRP). CRP, which is mainly produced by the liver, circulates in the bloodstream and is a standard marker for inflammation in the body. We also know that CRP levels tend to rise as we get older, and it may one of the factors involved in the increasing rates of cardiovascular diseases, diabetes and Alzheimer’s disease as we age.

This was a cross-sectional study that focused on baseline test results from 132 sedentary, independently living individuals aged 60 to 83 (47 males; 85 females) who had been recruited to participate in the Immune Function Intervention Trial (ImFIT), a randomized longitudinal trial designed by Woods and funded by the National Institute on Aging to examine the relationship between exercise and immune function.

Participants included only individuals who did not take medications that included corticosteroids, which could interfere with immune measurements. Smokers and/or those with severe arthritis, a history of cancer or inflammatory disease, chronic obstructive pulmonary disorder, uncontrolled diabetes mellitus, congestive heart failure, recent illness or vaccination, or a positive stress test were excluded.

The physical fitness of subjects was assessed through a battery of tests that measured such variables as fatigue, blood pressure, oxygen intake and carbon dioxide elimination and heart-rate recovery in conjunction with exercise on a walking treadmill. Tests also were administered to determine the subjects’ levels of physical activity, physical fitness, emotional stress and body composition, including bone density and body fat. Blood samples also were drawn to measure CRP levels.

The results were published in a recent issue of the Journal of the American Geriatrics Society.

It is important that they measured body fat. We know that increasing the amounts of intra-abdominal fat lead to an increase in inflammation: a fat tummy becomes a factory for inflammatory mediators.

The most interesting findings related to heart rate recovery following exercise.

The speed at which people were able to get back to their resting heart rate after a strenuous exercise test was inversely related to the levels of CRP. That means that individuals who had better parasympathetic tone had lower levels of inflammation.

And as any gym rat will tell you, one of the best-known ways improve parasympathetic tone is with aerobic exercise. When an unfit person exercises it can take a long time for his or her heart rate to come back to normal. As you get back into doing regular exercise, your resting pulse rate falls and so does the time that it takes for your heart rate to recover after exercise.

Since the study was cross-sectional, i.e. the researchers took a snapshot of the participants’ reactions and measurements at a single, fixed point we cannot say anything about cause and effect relationships.

The research confirms the conclusions of previous research that has indicated that high body fat is related to high inflammation and high fitness to low inflammation, though the researchers did not parcel out total body and abdominal fat. But this new research also suggests that physical fitness may be associated with a decrease in inflammation that is independent of body fat, and that it may be mediated by the parasympathetic nervous system: high parasympathetic tone is related to low inflammation.

So the nervous system may be the key player linking fitness, fatness and inflammation.

If this is correct, exercise alone will likely not be the whole answer. We also need to address other factors that modulate the activity of the parasympathetic nervous system including:

  • Physical, psychological and social stress
  • Adequate good quality sleep
  • Diet and nutrition: there may be foods that can increase stress on the autonomic nervous system
  • Adequate hydration: dehydration can be a major stressor on the body
  • Breathing: shallow breathing and hyperventilation are all known to stimulate the sympathetic nervous system and damp down the calming activities of the parasympathetic nervous system


Men, Exercise and Broken Bones

One of the problems that we all face as we get older is that unless we are careful, our bones can gradually become weaker. This is a particular problem in women, but a growing body of research indicates that men can run into trouble as well. At one end of the spectrum is “osteopenia:” a reduction in bone mineral density, and at the other end of the spectrum is full-blown osteoporosis.

The reason for taking the problem so seriously is that any degree of thinning of the bones can predispose us to so-called “osteoporotic fractures.” Sad to say, serious fractures are common among older people and can have devastating consequences, particularly if a hip is broken. Man people find it difficult to walk again. For years now we have recommended that women should take exercise to reduce the risk of thinning of their bones, particularly after menopause. But now research published in PLoS Medicine indicates that men who participate in sport or other vigorous activity may also reduce their risk of fractures.

Karl Michaelsson and colleagues at University Hospital, Uppsala, Sweden, report research in which over 2000 men who were initially studied in 1970-1973. The amount of physical activity that they took outside working hours was recorded, and then they were questioned again as they aged. Each of the surviving men was questioned again when they were aged 60, 70, 77, and 82. About half of the men were still alive at the end of the study, and the researchers recorded the number of fractures that the men had suffered during the 35 years of the study.

Based on the answers to the questions on physical activity at the start of the study, the researchers divided the men into three groups: those whose lifestyle was considered to be ”sedentary,” those whose leisure activities included some walking and cycling and those who participated in sports for at least 3 hours a week. These were referred to as the low, medium, and high-activity groups. Over the 35 years, 428 men had at least one fracture and 134 broke a hip. However, there were significant differences between the groups. 20% of the low-activity men had fractures, compared with 13% of those with medium activity and only 8% of those in the high-activity group. Of greatest importance was that the chance of having a hip fracture – the worst type of broken bone in an older person – was dramatically reduced by increased activity.

The researchers conclude that taking exercise reduces the risk of osteoporotic fracture in men. Participating in sports seems to be particularly effective: they calculated that one-third of fractures could be prevented if men could be persuaded to take part in sports regularly.

There is also an excellent summary by Harri Sievänen and Pekka Kannus from Tampere in Finland. As always each entire article is available online.

And I am to get my running shoes this very instant…


Burning Fat And Carbs

I was just flipping through a few magazine articles about diet and exercise and it amazed me how each writer was telling the reader that THIS was THE TRUTH about how to exercise and burn calories, and yet many contradicted each other.

This confusion and attempt to insert some order and certainty should not be too much of a surprise: there is still an enormous amount about metabolism that is simply not known. All of the articles were well written and well intentioned. Yet I am sure that many of the writers probably do not realize how much of what they are saying is guesswork!

The whole field of exercise and metabolism remains in a state of flux, though good progress is being made.

In a some new research from the Copenhagen Muscle Research Center at the University of Copenhagen in Denmark has been published in the Journal of Physiology, that helps us to understand a little more about the way in which muscles metabolize during exercise.

During exercise and physical activity, the primary fuels used by muscles are carbohydrate and fat. When you do mild exercise you tend to burn relatively more fat and less glucose. But as the exercise becomes more intense, a higher percentage of the energy demands of the muscles are supplied by glucose, until at the highest intensities almost only carbohydrates are used. One key question for any aspiring exerciser is how and why this happens? Is the shift in fuel source a property of the muscle itself, or does it represent the interplay between what is happening in the muscle and the exercise-related responses in the rest of the body.

The research looked at muscle fuel utilization in the quadriceps muscle during graded exercise done with only one leg. Nine healthy males did the one-leg exercise at 25, 45, and 85% of maximal workload. Their results showed that when only a small mass of muscle is contracting, the shift in fuel source from fat to glucose with increasing intensity does not happen. The explanation is that blood flow and oxygen supply are easily able to keep up with the demand.

The key to understanding the shifts in fuel source do not lie in the muscles at all, but in adaptations in the whole body during exercise. The oxidation of fat during exercise requires a fine interplay between the cardiovascular, neurological, endocrine and muscle metabolic systems.

The research also helps explain why athletes “hit the wall” during events like a marathon: the body can no longer switch fuels efficiently.

There are also some implications for the adaptations made in middle-aged adults who are using exercise to prevent or treat conditions like diabetes or obesity.

What we need to do is use slower training methods with good quality loose breathing to maximize oxygenation of the blood. This in turn allows fat oxidation to be maintained even during intense exercise with a large muscle mass.

And it looks as if we are heading back to the idea that cardiovascular work should be done before we start lifting.

Yoga and the Brain

Depression and anxiety are increasingly common throughout the world, and although each may be a consequence of psychological and environmental stresses, there is also a genetic predisposition and an increasing number of reproducible disturbances in the brain.

In recent years, there has been increasing interest in the role of brain gamma-aminobutyric acid (GABA) levels, which is the brain’s primary inhibitory neurotransmitter, in both depression and anxiety, following the finding that each may be associated with low levels of GABA in different regions of the brain.

There have also been reports that yoga may help stress and anxiety as well as depression.

Now colleagues from Boston University School of Medicine (BUSM) and McLean Hospital have found that practicing hatha yoga may elevate brain GABA levels.

This new research is published in last month’s issue of Journal of Alternative and Complementary Medicine.

The researchers used magnetic resonance spectroscopic imaging to compare the GABA levels of eight subjects before and after one hour of yoga. The control group consisted of 11 people who read a book or magazine instead of doing yoga. They found a twenty-seven percent increase in GABA levels in the yoga practitioner group after their session, but no change in the comparison subject group after an hour spent reading.

It is too early to start recommending yoga for the treatment of depression or anxiety, but it is fascinating that it will produce changes in brain chemistry that are very similar to those that we hope to achieve with other forms of therapy.

Motivational Interviewing and Exercise

Researchers from Germany have
re-visited the interesting topic of the association between aerobic
exercise and psychiatric disorders, and presented their work in a
poster (NR20) at the 2007 Annual Meeting of the American Psychiatric
Association in San Diego, California, this morning.
There is good evidence
that exercise can help people with depressive and some other
psychiatric disorders. Unfortunately, like everyone else, people with
psychiatric problems have trouble in developing regular exercise habits
or staying with the program. The mood problem itself may stop them, or
the physical pain that so often accompanies depression.

223 people were screened at the time of admission to hospital and 82
decided to participate. That is a disappointing but unsurprising rate
of participation. The patients were offered a three-month
running/walking program that they could continue after discharge. They
all had weekly meetings that included exercise-related psychoeducation,
stretching and 40-50 minutes of aerobic exercise.

In addition the experimental group received brief interventions using motivational interviewing,
a specific technique to foster changes in behavior. Motivational
interviewing is a client-centered non-judgmental and
non-confrontational appraoch to change that attempts to increase
peoples’ awareness of the potential
problems caused, consequences experienced and risks faced as a result
of the behavior in question. Alternatively, therapists help clients
to try and envision a better future and to become increasingly
motivated to achieve
it. These strategies seeks to help clients think differently
about their behavior and ultimately to consider what might be gained
through change.

In people who had the motivational interviewing, the completer rate
was 78%, compared with 33% in the control group who just had the
psychoeducation, stretching and exercise.

The patients’ initial self-assessments concerning the importance and
efficacy of regular exercise for their individual recovery did not
predict compliance.

This confirms that motivational interviewing is highly effect in
helping people with mental illness initiate and continue with a regular
exercise program.

This new research adds to a body of evidence that has shown that motivational interviewing can be helpful in the treatment of obesity, weight management in women with type 2 diabetes, exercise in women with fibromyalgia, quality of life in people with chronic heart failure and physical exercise in long-term cancer survivors.

It may also be very helpful in people who need to exercise yet have no psychiatric problems: any of us!

Non-pharmacological and Lifestyle Approaches to Attention-Deficit/Hyperactivity Disorder: 5. Exercise, Environment and Sleep

One of the most valuable things to do to help children or adults with ADHD is to help them to structure their time.

All the approaches that we have already discussed, from medications to diets, herbs and homeopathy are all tools designed to help people get to the point where they can create, accept and maintain more structure in their lives. Exercise, the environment and regular sleep are all essential contributors.

Exercise
Aerobic exercise may be particularly helpful for people who also have a mood disorder or anxiety probably by reducing inflammatory mediators in the blood.

There is a movement therapy called eurythmy that was developed by Rudolf Steiner. It is quite popular in central Europe, and there has been a report that it could help children with ADHD.

Environment
There is evidence that children with ADHD do better if they are outside, and even being a green room seems to help them.

There are plenty of anecdotes about children and some adults with ADHD improving if they have classical or New Age music in the background. Paradoxically some like and claim benefit from “heavy metal.” There is recent evidence from New Zealand indicating that music therapy may contribute to the reduction of a range of ADHD symptoms in adolescents, as it does in younger children. With the advent of the iPod, it is easy to make a playlist of music that helps attention and concentration.

The data on the effect of watching television, computer time or playing video games is a mixed bag. There are people who say that children under the age of three should not watch television at all, and the American Academy of Pediatrics recommends that children under the age of 2 years should watch no television, and that television time should be limited to less than 2 hours daily in older children. The research data has not produced a clear answer one way or the other. Some of the most recent research does suggest a link between the amount of time that children spend
watching television and attention-deficit/hyperactivity disorder, but
it remains unclear as to whether elevated levels of television viewing
are the cause or result of ADHD symptoms. Other researchers have failed to find a connection. The best thing is to play safe and to keep television viewing to a minimum: there are so many other things for a child to be doing.

There have been questions about whether other environmental factors, particularly lead, mold and Candida could cause ADHD.

Lead toxicity is well-known to cause neurological problems, but studies of a link between lead levels and ADHD have usually failed to find a link, and in a study in which children with minimally elevated lead levels were given a drug – penicillamine – to remove lead, there was no change in ADHD rating scores. So it is unlikely that lead is a factor in most children.

Because of the high rates of allergies in people with ADHD, there have been attempts to see if mold or other environmental pollutants could be causing ADHD. So far the data has drawn a blank.

Another environmental factor that has been look at is the yeast Candida albicans. It can produce nasty infections in people with compromised immune systems. But in addition, some people have claimed that Candida infections can cause an array of medical problems, including ADHD-like symptoms. People who are thought to have Candida have been treated with diets as well as the antifungal agent nystatin, with mixed results. It would be good to do a formal study of Candida in ADHD and see if there is a link and if treatment helps. So far we just do not have one.

Sleep
Sleep disturbances are extremely common in ADHD. They often get better once an individual is treated, but it is still a good idea to practice good sleep hygiene.

  1. Stress management
  2. Exercise a couple of hours before retiring
  3. Keeping mentally stimulated until it is time for bed
  4. Though we want to have a regular bedtime and bedtime ritual, to begin with don’t go to bed until you are tired
  5. No caffeine, alcohol or nicotine after 6pm. (Preferably, of course, no nicotine ever!!) {Remember that many over the counter painkillers contain caffeine, as does chocolate}
  6. Try to keep the bedroom atmosphere relaxing, and establish a sleep ritual
  7. Keep the room quiet and dark
  8. If you like aromatherapy, lavender and chamomile are usually best
  9. If you cannot sleep, get up and do something relaxing: struggling to go to sleep is virtually impossible.
  10. Do not have a television in the bedroom. Bedrooms should be reserved only for sleep in children and for one other activity in adults
  11. Always get up at the same time in the morning, to try and re-set your brain, and as soon as you get up, be exposed to as much bright light as possible

Twelve Tips to Reduce Your Risk of Colorectal Cancer

Colon cancer, or, more accurately colorectal cancer, includes cancerous growths in the colon, rectum and appendix. It is the third most common form of cancer and the second leading cause of death among cancers in the Western world. Colorectal cancer surpasses breast and prostate cancers as a leading cause of cancer deaths in both men and women.

And the key point is that with early screening and a few simple dietary modifications, you can dramatically reduce your risk of getting it.

These are the 12 Tips to Slash Your Risk of Colorectal Cancer

  1. Receive regular colorectal cancer screenings beginning at age 50 if you are at normal risk
  2. If you are at higher risk due to a personal or family history of colorectal cancer, other cancers or inflammatory bowel disease have a discussion with your health care provider about screenings before age 50
  3. Eat between 25 and 30 grams of fiber each day from fruits, vegetables, whole grain breads and cereals, nuts, and beans
  4. Eat a low-fat diet: colorectal cancer has been associated with diets high in saturated fat, particularly fat from red meat
  5. Eat foods with folate, such as leafy green vegetables
  6. Try to drink at least 80 fluid ounces of pure water a day unless you have a medical reason for not doing so
  7. Drink alcohol in moderation: 2 units of alcohol or less each day
  8. If you smoke, here is another good reason for quitting. Alcohol and tobacco in combination are linked to colorectal cancer and other gastrointestinal cancers
  9. Exercise for at least 20 minutes three to four days a week. Moderate exercise such as walking, gardening or climbing stairs may help reduce your risk
  10. If you get any persistent symptoms such as blood in the stool, a change in bowel habits, weight loss, narrower-than-usual stools, abdominal pains or other gastrointestinal complaints, it is essential to report them to your health care provider
  11. Maintain a healthy weight. Obesity may increase the risk of colorectal cancer
  12. Maintain a good intake of calcium and vitamin D: this combination has been shown to reduce the risk of colorectal cancer

For more information, I recommend visiting the Web site of the American Cancer Society.

I keep their details in the “Resources” section on the left hand side of this blog.

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