Archive for Exercise
Exercise and inflammation
Posted by: | CommentsThe relationship between exercise and coronary heart disease has been the subject of continued medical research. CHD as an inflammatory manifestation is also an accepted connection. A study has now made the connection between exercise and inflammation, although I don’t think that there is a cause and effect relationship between the two variables. Researchers from the University of Illinois examined parasympathetic and sympathetic activity on C-reactive protein (which is an indicator of inflammation) — by investigating heart-rate recovery after exercise. The sympathetic nervous system gets activated during exercise, while the parasympathetic system slows the body down when the exercise is finished.
So here’s how exercise could be helpful in managing inflammation:
“(When) you’re exercising, your sympathetic nervous system will be on, increasing your heart rate, your respiration, etc. Once you stop … the parasympathetic nervous system kicks in to get everything back down to baseline levels. The quicker the individuals were able to get back to their resting heart rate after a strenuous exercise test was inversely related to their CRP. (Individuals) who had better parasympathetic tone had lower levels of inflammation.” said Victoria Vieira, the study’s primary author and designer.
As we all know, the parasympathetic response is activated/trained by such mind-body pursuits as yoga (either in asana or pranayama practice), chi gung, meditation, and heart rate variability training.
What this study shows is that “traditional” exercise (assuming it’s not excessive) can help modulate inflammation by training the “relaxation response.”
In the ideal world, when you are trying to achieve optimal healthy weight, I would argue that combining both types of physical activity would be the best option. This means doing strength training, cardio, and yoga.
Strength training guidelines
Posted by: | CommentsThe guidelines of the American College of Medicine (ACSM) advocates the use of simpler training protocols for both beginners and experienced trainees. Here are some key ideas for effective weight training:
* Intensity can be effectively measured by “perceived effort.”
* A wide range of reps per set can be equally effective, depending on the effort spent.
* There is no evidence that there is a separate way to train for strength or endurance. Getting stronger also increases muscular endurance. (I’m not quite sure about this one actually. I think that the concept of training specificity can negate this claim.)
* Take about 3 seconds to raise the resistance and about 3 seconds to lower the resistance using a full range of motion for each repetition.
* To increase strength, training has to produce an overload beyond a minimal threshold. Focus on progression without compromising the form of the exercise, and using as complete a range of motion as is possible.
* The intensity of training can be increased by increasing the weight, number of repetitions, and by reducing momentum through increasing the repetition’s duration.
* A variety of exercises can be used for each muscle group, with some physiological and psychological benefits against “staleness.” The overall evidence does not support the superiority of higher volume training — eight to 10 exercises performed two to three days per week is sufficient.
Lifestyle choices and cancer prevention
Posted by: | CommentsThe National Cancer Institute provides the following recommendations regarding diet and physical activity:
1. Adopt policies and provide funding to improve the built environment to encourage physical activity. For example:
• Address safety issues that discourage physical activity.
• Plan new communities that encourage physical activity.
• Retrofit existing communities to encourage physical activity (e.g., install sidewalks, improve community centers, parks, playgrounds).
2. Coordinate U.S. agricultural subsidy and public health policy related to diet and nutrition to improve the food supply and help ensure that all people have access to affordable, healthy food. Specifically:
• Structure farm supports to incentivize/encourage increased production of fruits and vegetables; limit farm subsidies that promote the production of high fructose corn syrup for use in food.
• Support healthier food choices by restructuring regulations governing acceptable food choices allowed by the Women, Infants, and Children Program, Headstart, and school lunch programs.
3. Improve access to affordable, healthy foods in urban communities; implement “fair food” policies similar to fair housing policies.
4. Regulate and monitor food advertising in media targeting children.
5. Reinstate physical education at meaningful levels in grades K-12 andexpand physical activity offerings to include individually-oriented activities (e.g., yoga, weight training) that could be maintained for life. Though not an ideal measure, include body mass index (BMI) measurement, as adapted for youth, as part of school physical fitness assessments and provide this information to parents. Parents also should receive information about the relationship of BMI to disease risk and how to decrease BMI through behavioral change.
6. Replace unhealthy food choices in school food service facilities and vending machines with healthful foods and beverages. Include information in elementary and secondary school health curricula about the meaning of energy balance and how to read and interpret food labels and other health information related to diet and nutrition.
7. Make nutrition information about restaurant foods readily available on menus and understandable to customers.
8. Increase support and incentives for employee wellness (e.g., diet, fitness). Provide healthier choices in workplace food service facilities/vending machines and provide economic subsidies that encourage healthy food choices.
9. Provide coverage for nutrition counseling and fitness promotion as part of all comprehensive health benefit packages as an accepted mechanism for reducing risk and preventing disease.
10. Measure BMI as part of routine physical exams and counsel patients about the meaning of this measurement. Educate patients about the necessity of balancing food intake and physical activity to avoid and reverse obesity.
11. Seek out opportunities to increase personal and family fitness and health.
Exercise guidelines and weight loss
Posted by: | CommentsGuidelines from the American Heart Association and the American College of Sports Medicine recommend that adults should: (a) engage in moderately intense exercise for at least 30 minutes five days a week or vigorous exercise at least 20 minutes three days each week, and (b) weightlifting exercise to work on muscular strength and endurance, with eight to 10 different exercises on two nonconsecutive days a week. The new guidelines urged people 65 and older to lift weights and work on flexibility exercises and balance training.
One of my new clients has been running 5 days a week for 45 minutes to an hour for about a year, before he approached me for help. He wanted to build more muscle, and control his blood sugar. In my initial meeting with him it appeared that his diet was a little bit off. We tweaked this a little bit. I also gave him a fifteen minute dumbell workout (20 lbs each) that he did 5 days a week.
Six weeks later, he called me and reported that he lost 16 pounds (he’s now 135 pounds on a 5′6” frame), and most importantly also lost two inches off his waist. He’s extremely excited because his six-pack abs is in sight. Most importantly, his blood sugar is now normal – with no medication — simply from the slight diet modification and weight training routine I gave him.
Moral of the story: A high nutrient diet, plus an intelligently designed weight training program can really turbo charge your health and weight loss goals.
Health benefits of moderate exercise
Posted by: | CommentsA new study finds that moderate exercise may be able to provide better protection against diabetes and heart disease than a more intense workout regimen. Researchers from the Duke University Medical Center report that “a modest amount of moderately intense exercise is the best way to significantly lower the level of a key blood marker linked to higher risk of heart disease and diabetes. Some of the benefits achieved through moderate exercise seem to last much longer than the benefits gained through more intense training”
Exercise did not significantly changed the levels of low-density lipoprotein (LDL cholesterol). Duration and intensity of exercise did improve levels of high-density lipoprotein. Low amount/moderate intensity exercise significantly lowered levels of triglycerides, which is correlated to a person’s risk for diabetes and heart disease.
I think that “intense” exercise (e.g., interval training) has its role in a well-balanced fitness program. It increases a person’s anaerobic energy system, and creates a margin of safety from a functional standpoint. IMHO, one is better able to handle the occasional physical stresses in daily life much more effectively. Strength training would also be a necessary component in creating an optimal exercise routine.
Is moderate exercise helpful?
Posted by: | CommentsCurrent recommendations for 30 minutes of moderately strenuous exercise at least five days of the week is a reasonable goal. However, few people meet this requirement. Now a small study published in the Journal of Epidemiology and Community Health indicates that even relatively low levels of weekly exercise can positively impact high pressure and improve overall fitness.
The research indicates that even half hour of walking done three time as a week has some effect of pressure and waist/hip measurement to affect the risk factors related to cardiovascular mortality.
Personally, I think it all comes down to creating a positive habit of engaging in even mild to moderate exercise on a daily basis. I think it’s easier to form daily rituals compared to a “3 to 4 times a week” exercise routine. It’s better to pick a modest goal, of say 15 to 20 minutes brisk walking on a daily basis, then stick to it for a few months. Only when this ”minimum habit” is solidly in place can one then think of increasing intensity and/or duration.
Brain health and aging
Posted by: | CommentsThe secret to keeping our mind intact as we age? Research sponsored by the MacArthur Foundation Network on Successful Aging shows that there are four variables that affect mental fitness: physical activity, lung function, levels of education, and feelings of self-efficacy. The scientists believe that that regular exercise stimulates flow to the brain and promote nerve growth. This results in denser neuronal networks that are more resistant to disease. Moderate aerobic workouts can accomplish this.
Animal studies also support the hypothesis that mental and physical activity enhance brain health. The Beckman Institute for Advanced Science and Technology in Urbana, Illinois found that rats developed 25 percent more connections between their neurons compared to rats that did not get any mentally stimulating tasks. Rats that exercised on a treadmill developed more capillaries in their brains (which increased the flow to their brains) versus their couch potato peers.
Exercise and energy
Posted by: | CommentsStudies spanning different populations – from healthy subjects to cancer patients, as well as those with chronic conditions like diabetes and heart disease – show the benefits of exercise. In addition, although it may seem counterintuitive that expending energy through exercise would increase feelings of energy and reduce fatigue, research has shown that the levels of energy-promoting and mood-enhancing neurotransmitters such as dopamine, norepinephrine and serotonin significantly increase under exercise conditions.
So instead of artificial energy enhancers (e.g., caffeine and “energy drinks”) it’s probably more effective to go for a brisk walk, pump some iron, or skip rope for a few minutes. I find this approach very effective, specially when tackling mental tasks that require high levels of alertness and problem solving skills.
There’s a new study claiming that lowering blood pressure (BP) below the standard 140/90 (systolic/diastolic) is not beneficial. While this has been the de facto BP target of physicians and patients, there has been a trend towards lower targets by hypertension experts setting treatment guidelines. According to the study, “using more drugs in lower target groups did achieve modestly lower BP. However, this strategy did not prolong survival or reduce stroke, heart attack, heart failure or kidney failure. At present there is no evidence to support aiming for a BP target lower than 140/90 in any hypertensive patient.”
It’s very easy to take this study out of context. Notice that the study refers to the use of anti-hypertensive drugs to lower BP. There is a vital difference between using drugs to lower BP and using lifestyle measures (i.e., a plant based diet, exercise, and maintaining a healthy body weight).
What the study is saying is that if one is using BP-lowering drugs, it’s not worth it to take more drugs in order to go below 140/90. The study is NOT saying that 140/90 is a “healthy” metric. Neither is it refuting the benefits of a healthy diet and lifestyle approach that results in levels like 115/70. (The current article in Medscape cites the Lewington meta-analysis of one million patients showing convincing evidence that people have fewer strokes and heart attacks when their ‘usual’ BP is 115/70 compared with those with a ‘usual” BP of 130/90).
It is simply saying that pumping more drugs simply to lower BP beneath 140/90 is marginally effective.
I like to think of BP as an “effect” (or “dependent variable,” in research-speak). The cause (or independent variable) of the metric is actually how we eat and live. The better we eat, the more consistently we exercise intelligently, the better our BP fares. What has happened in today’s medicalist gestalt is that we tend to confuse BP (or some other metric) as the “root cause” of the disease, and therefore any intervention (i.e., medication) that causes BP to go lower is “good.” We’re targeting the symptom, rather than the cause of the disease itself.
This is not to knock antihypertension medication, or any “symptom targetting” protocol (such as statins for high cholesterol). Ultimately, what we need to address are the basic issues causing the symptoms in the first place. In the majority of cases, the causes would be being overweight or obese, lack of exercise, and eating a nutrient-poor, calorie dense diet.
Exercise and brain function
Posted by: | CommentsExercise causes a protein called IGF-1 to travel across the -brain barrier. Once in the brain, it gives orders to produce an important substance called brain-derived neurotrophic factor (BDNF), which serves as the “fuel” for thinking. Regular exercise naturally builds up the levels of BDNF in the brain, allowing new neural pathways (i.e., learning) to occur.
Scientists have also discovered that neurogenesis, i.e., the production of new neurons in the brain, can be instigated by cardiovascular exercise. BDNF production affects the hippocampus (specifically, the dentate gyrus) which controls memory and learning.
Increased levels of this substance appear to reverse the age-induced deterioration of this part of the brain. In addition, exercise also increases the size of the frontal lobes, the areas responsible for higher level mental tasks such as planning and decision making.
The neuro-chemical relationship between exercise and mental functioning is increasingly being clarified by the research. The results indicate that exercise facilitates learning and slows down the deterioration brought about by the aging process.
We all know what needs to be done…
