Category Archives: Exercise

February 18, 2012 · 4:59 AM

Book Review: Choose to Lose: The 7-Day Carb Cycle Solution

I saw the author of Choose to Lose on a rerun of Dr. Oz in early January.  Then I checked the book’s sales rank at Amazon.com (22nd overall—a blockbuster in my view).  (Don’t get me wrong; I’m not in the habit of watching Dr. Oz.)  Here’s my review of 2012’s Choose to Lose: The 7-Day Carb Cycle Solution, by Chris Powell.  The book is for the general public, not people with diabetes.  I give it three stars per Amazon.com’s five-star system.

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Will it work?  Certainly for some, quite possibly a majority.  Like most published programs, it’ll work for for you if you work the program.  Question is, can you do it?

The underlying idea is to alternate high-carb and low-carb eating days, which supposedly revs up your metabolism and tricks your body into thinking it’s not on a diet so it won’t go into self-preservation starvation mode.  Mr. Powell calls this carb cycling.

The high-carb days are also low-fat, and the low-carb days are low-calorie.  Actually, both days are reduced-calorie if your goal is the most dramatic results.  A moderate calorie deficit is built into the program.  Women get about 1350 calories; men around 1700.  Those levels are lower than necessary. Other than that, it appears you’ll get all the other nutrients you need, which is good.

I can see how the diet would work for some because it drastically reduces consumption of our most fattening carboydrates.  Loser Choosers aren’t supposed to eat baked goods, white flour, refined sugar, beer, candy, chips (crisps, for those in the UK), conventional breads, cookies, crackers, ice cream, sugar-sweetened beverages, corn syrup, and milk.  I suspect if we all stopped eating those right now, the overweight rate in the U.S. would drop by at least 10% in the next 12 months.

The author allows no wheat or white rice except for whole wheat bread and pasta.  Potatoes, peas, and corn made it to the “approved” list.  You eat mostly natural, minimally processed foods (yay!).

I don’t know Mr. Powell, but he comes off as earnest, honest, compassionate, experienced, and intelligent.  He’s not a scammer.  Mr. Powell has more faith than I do in the benefits of exercise for weight loss.  He notes that nutrition is more important.  We agree that exercise is often critical for prevention of weight regain.  He barely, if at all, mentions the benefits of exercise in prevention of disease and prolongation of longevity.  His well-illustrated exercise recommendations are  a good start for fitness beginners.  He wants you to exercise for 10-30 minutes on six days a week, doing a combo of cardio intervals and body weight resistance training.  No expensive equipment to buy.

Carb cycling like this is supposed to “boost your metabolism to burn fat quickly.”  It does not, to any clinically meaningful extent.  Nor is carb cycling mentioned in this year’s massively referenced The Smart Science of Slim.  Contrary to the author’s opinion, neither eating five meals a day nor eating carboydrates revs up your metabolism.

Mr. Powell provides some helpful mind tricks to prepare you for a lifestyle change.

My favorite sentence: “Success doesn’t just happen.  It’s a result of the 4 Ps of action: Planning, Preparation, Performance, Persevance.”

My least favorite sentence: “Water is imperative for loosing [sic] weight.”  A close second was: “Alcohol is a powerful diuretic (it flushes water out of your system), so it dehydrates you, causing water retention and bloating for one to three days after you drink.”  Huh?

I like his incorporation of cheat meals, although he allows more than I would.  To his credit, the all-important maintenance phase is covered well.

Mr. Powell recommends supplementing with probiotics and digestive enzymes, being unaware of their uselessness for most dieters.

I note that Amazon sells Choose to Lose by Dr. Ron and Nancy Goor, and The Carb Cycling Diet by Dr. Roman Malkov.  Coincidence ? 

In terms of complexity, the program is about average. 

I wonder if you’d do just as well by swearing off the fattening carbohydrates I listed above.  If you’re looking to lose weight, you could do a lot worse than Choose to Lose.  And you could do better.

Steve Parker, M.D.

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December 14, 2011 · 3:30 AM

What About “The Biggest Loser”?

Probably not watching The Biggest Loser

Dr. Barry Sears (Ph.D., I think) recently wrote about a lecture he attended by a dietitian affiliated with “The Biggest Loser” TV show.  She revealed the keys to weight-loss success on the show.  Calorie restriction is a major feature, with the typical 300-pounder (136 kg) eating 1,750 calories a day.  On my Advanced Mediterranean Diet, 300-pounders get 2,300 calories (men) or 1,900 calories (women). 

Although not stressed by Dr. Sears, my impression is that contestants exercise a huge amount. 

Go to the Sears link above and you’ll learn that all contestants are paid to participate.  In researching my Conquer Diabetes and Prediabetes book, I learned that the actual Biggest Loser wins $250,000 (USD).  Also, “The Biggest Loser” is an international phenomenon with multiple countries hosting their own versions, with different pay-off amounts.  A former Biggest Loser, Ali Vincent, lives in my part of the world and still has some celebrity status.

This TV show demonstrates that the calories in/calories out theory of body weight still applies.  Including the fact that massive exercise can help significantly with weight loss.  In real-world situations, exercise probably contributes only a small degree to loss of excess weight.  The major take-home point of the show, for me, is that you can indeed make food and physical activity choices that determine your weight.

Most of us watch too much

I know losing 50 to 10o pounds of fat (25–45 kg) and keeping it off for a couple years is hard; most folks can’t do it.  Do you think you’d be more successful if I gave you $250,ooo for your success?

Steve Parker, M.D.

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October 9, 2011 · 2:18 AM

Does Diminished Work Activity Explain Our 50-Year Overweight Trend?

Daily work-related energy expenditure over the last half-century in the U.S. has decreased by over 100 calories.  This may well explain the increase in body weights we’ve seen, according to a 2011 article in PLoS ONE.

I sorta hate to open this can o’ worms, but it’s important.  As a population, are we fat because we eat too much or because we burn too few calories in physical activity?  Or is it a combination?  The correct answer may help us learn how to reverse the trend.

Methodology

Authors of the study at hand estimated the amount of energy (calories) necessary to perform various jobs, then noted changes in numbers of people employed in those jobs over time.  In the early 196os, for example, nearly half of U.S. jobs required at least moderate intensity physical activity, compared to less than 20% demanding that degree of energy now.  The authors note the dramatic shift from manufacturing to service-type jobs over the last 50 years.  Service jobs, like mine, often entail a lot of sitting and standing around. 

They chose to ignore how much energy we expend in exercise, figuring what we do in a 40-hour work week overwhelms the 1-2 hours of  exercise we may do.

Researchers’ Findings and Conclusions

They found that work-related daily energy expenditure has decreased by over 100 calories over the last half-century, which (in the authors’ view) would account for a significant portion of the increased body weight we’ve seen.  Since physically demanding jobs are unlikely to see a resurgence, the authors advocate physically active lifestyles away from workplace. 

Discussion

Surveys indicate that only one in four of us fulfill the federal physical activity guidelines: 150 minutes a week of moderate intensity activity or 75 minutes a week of vigorous intensity activity.  When activity is actually measured with an accelerometer, only one in 20 achieve that lofty goal.  We over-estimate how much we exercise, and under-estimate how much we eat.

(If you want to emulate a Paleolithic lifestyle, you should probably shoot for an hour of exercise daily, not 20 minutes as above.)

The researchers cite studies showing significantly increased average per capita calorie consumption in the U.S. over the last several decades.  Some experts estimate the caloric increase is in the range of 500 a day for adults; the authors here think that’s too high but don’t offer a specific alternative. Looking at one of their references (Hall et al), they must think the increase is closer to 200 calories a day, comparing 2005 to 1975.

Several studies suggest that average daily energy expenditure has not decreased in developed countries, at least from the 1980s to the present.   A strength of the current study at hand is that it spans about 50 years, up to 2008.

My sense is that both calorie consumption (too much) and physical activity (too little) contribute to our overweight problem that started 40 or 50 years ago.  Excessive consumption is the predominant factor.  To “exercise off”  the calories in a Snickers candy bar, you’d have to jog for an hour.  If you’re watching your weight, you’ll have more success if you just skip the Snickers.

In case you couldn’t tell,  I still believe in the “calories in/calories out” model of overweight and obesity, aka “the energy balance equation.”  At the same time, I believe certain foods  are more fattening than others: concentrated sugars and refined starches.

Steve Parker, M.D.

References:

Church, T.S., et al.  Trends over 5 decades in U.S. occupation-related physical activity and their associations with obesity.  PLoS ONE, 2011, 6(5): e19657.  doi: 10.1371/journal.pone.0019657  

Swinburn, B., et al.  Increased food energy supply is more than sufficient to explain the U.S. epidemic of obesity.  American Journal of Clinical Nutrition, 2009 (90): 1,453-1,456.  

Hall, K.D., et al.  The progressive increase of food waste in America and its environmental impact.  PLoS ONE, 2009, 4(11): e7940.  doi: 10.1371/journal.pone.0007940

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June 27, 2011 · 5:20 AM

Exercise, Part 11: Target Heart Rate

To get the full health benefits of regular physical activity, you need to put some effort into it.  A leisurely hour-long stroll in the mall while window-shopping doesn’t pass muster, although that’s better than nothing.

One rough way to gauge whether you are working hard enough during aerobic exercise is to monitor your heart rate, also known as pulse.  Subtract your age from 220.  The result is your theoretical maximum heart rate in beats per minute.  Your heart rate goal, or target, during sustained aerobic exercise is a pulse that is 60 to 80 percent of your theoretical maximum pulse.  For example: maximum heart rate for a 40-year-old is 180 (220 – 40 = 180), so the target heart rate zone during exercise is between 108 and 144 (60 to 80 percent of 180).  Exceeding the upper end of the target zone is usually too uncomfortable to be sustainable.  Exercise heart rates below the target zone suggest you’re not working hard enough to reap the full long-term benefits of aerobic exercise.

Here’s how to determine your pulse.  After five or 10 minutes of exercise, stop moving and place the tips of your first two fingers lightly over the pulse spot inside your wrist just below the base of your thumb.  Count the pulsations for 15 seconds and multiply the number by four.  The result is your pulse or heart rate.  It will take some practice to find those pulsations coming from your radial artery.  If you can’t find it, ask a nurse or doctor for help.

Like all rules-of-thumb, this target heart rate zone isn’t always an accurate gauge of cardiovascular workout intensity.  For instance, it is of very little use in people taking drugs called beta blockers, which keep a lid on heart rate.

As you become more fit, you’ll notice that you have to work harder to get your heart rate up to a certain level.  This is a sure sign that your heart and muscles are responding to your challenge.  You may also want to monitor your resting heart rate taken in the morning before you get out of bed. Unfit, sedentary people have resting pulses of 60 to 90.  Athletes are more often in the 40s or low 50s.  Their hearts have become more efficient and just don’t need to beat as often to get the job done.

As you become more fit, you’ll also notice that you have more energy overall and it’s easier to move about and handle physical workloads. You’ll feel more relaxed and have a sense of accomplishment. Expect these benefits eight to 12 weeks after starting a regular exercise program.

Steve Parker, M.D.

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June 2, 2011 · 2:00 AM

Exercise, Part 10: What If I’m Markedly Obese?

The more overweight you are, the harder it will be to exercise.  At some point even light exercise becomes impossible.  Average-height women tipping the scales at about 280 pounds (127 kg) and men at 360 pounds (164 kg) aren’t going to be able to jog around the block, much less run a marathon.  These weights are 100 percent over ideal or healthy levels.  An actual “exercise program” probably won’t be possible until some weight is lost simply through very-low-carb eating, calorie restriction, or bariatric surgery.  The initial exercise goal for you may just be to get moving through activities of daily living and perhaps brief walks and calisthenics while sitting in a chair.

"I'll get started after I finish this cigarette."

Markedly obese people who aren’t up to the aforementioned extreme weights can usually tolerate a low-intensity physical activity program.  At 50 percent over ideal weight, an average-height woman of 210 pounds (95 kg) is carrying 70 excess pounds (32 kg) of fat.  Her male counter-part lugs around 90 pounds (41 kg) of unnecessary fat.  This weight burden causes dramatic breathlessness and fatigue upon exertion, and makes the joints and muscles more susceptible to aching and injury.  If you’re skinny, just imagine trying to walk or run a mile carrying a standard five-gallon (19 liter) water cooler bottle, which weighs only 43 pounds (19.5 kg) when full.  The burden of excess fat makes it quite difficult to exercise.    

If you’re markedly obese, several tricks will enhance your exercise success.  I want you to avoid injury, frustration, and burn out.  Start with light activity for only 10 or 15 minutes, gradually increase session length (e.g., by two to four minutes every two to four weeks) and increase exercise intensity only after several months.  Your joints and muscles may appreciate easy, low-impact exercises such as stationary cycling, walking, swimming, and pool calisthenics/water aerobics.  You may also benefit from the advice of a personal fitness trainer arranged through a health club, gym, or YMCA/YWCA.  Check out several health clubs before you join.  Some of them are primarily meat markets for beautiful slender yuppies.  You may feel more comfortable in a gym that welcomes and caters to overweight people. Hospitals are increasingly developing fitness centers with obese orthopedic, heart, and diabetic patients in mind.

Steve Parker, M.D.

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May 18, 2011 · 2:00 AM

Recreational Activities Are Not Necessarily Exercise

Exercise is not supposed to be fun.  If it is fun, then you should suspect that something is wrong.

The quote above is from an essay entitled “Exercise vs Recreation” by Ken Hutchins, posted at the Efficient Exercise website.  Skyler Tanner works at Efficient Exercise and his blog is one that I follow.  We have a strange connection.  Skyler grew up in Fountain Hills, AZ; I live about 20 miles from there.  He lives in Austin, TX, now; I lived there for eight years.

Here’s another quote from that essay:

One pound of human fat can support the energy demands of running 35-45 miles, probably more.  This would require the average man to run for 6-8 hours.  He would burn the calories he could easily ingest in as many minutes.

Hutchins’ essay is thought-provoking.  It may change the way you think about exercise.

Steve Parker, M.D.

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April 8, 2011 · 2:00 AM

Exercise, Part 9: Realistic Goals If You’re New to Exercise

FITNESS

Sustained physical activity requires that your heart pump blood to the lungs and to the exercising muscles.  The muscles extract oxygen, sugar, and other nutrients for use in chemical reactions that enable the muscle to keep moving (contracting).  To say that someone is physically fit simply means that the heart easily pumps a large volume of blood and the muscles extract and use nutrients very efficiently.  The heart, after all, is just a hollow muscle that pumps blood.  If you stimulate your heart muscle through exercise, it will become more powerful and able to pump more blood.  Regular sessions of physical activity increase the metabolic efficiency and power of your other muscles, too.  There are various degrees of fitness, with professional and Olympic athletes at the extreme upper end.

GETTING STARTED

I’ve had otherwise healthy overweight patients so “out of shape” that walking 20 yards to the mailbox was a real chore.  They were tired and panting when they got to the mailbox and had to rest a bit before returning to the house.  These folks are habitually sedentary and dramatically overweight.  But you need not feel too sorry for them.  After starting and maintaining an exercise program, these unfit people achieve the greatest degree of improvement in fitness level.  They make more progress, and faster, than those who begin with a greater level of fitness.

The way to achieve aerobic fitness is to regularly challenge your large muscles to perform sustained physical activity.  “Regularly” means at least four days a week, if not daily.  Left alone, your muscles don’t want to do much other than just get you through your day comfortably, without effort or aching or cramps.  You must challenge them to do more, work a bit harder, tolerate a little aching.  You’ll know you’re challenging them during exercise when you perceive that mild to moderate effort is required to keep the activity going.  You should be mildly short of breath, perhaps even perspiring lightly, yet still able to converse.  “Sustained” physical activity means at least 30 minutes in a day.  Most people find it a better use of their time to exercise for 30 minutes continuously rather than break it up into five or 10 minutes here and there.

Discontinuous activity (e.g., 10 minutes thrice daily) probably is just as good. If you think about it, there are many easy ways to increase your discontinuous physical activity. Consider taking the stairs instead of the elevator, parking far from the supermarket or workplace doors, walking the golf course instead of riding a cart.

(The exercise model above is “old school,” which isn’t necessarily good or bad.  Some newer scientific studies suggest that you can achieve comparable levels of fitness with much less time exercising, if you do it intensely.  An example is high-intensity interval training (HIIT).  That’s worth a blog post or two by itself.  I also leave strength training—also an important aspect of fitness—for another day.)

If you’re starting out in poor shape, you won’t be able to do 30 minutes of any exercise without adverse effects.  Don’t even try.  The worst thing you could do at this point is injure yourself or have such a horrible experience that you give up entirely.  Thirty minutes of daily activity is your goal to achieve over the next four to 12 months.  Moderate to high levels of fitness will take you six to 24 months.  The most important thing when getting started is to exercise at least a little, five to 10 minutes, on most days of the week.  And don’t overdo it in terms of intensity. Start low, go slow.  After three months, exercise will be a habit.  Prolongation of your exercise sessions will be easy as your amazing body responds gradually to the workload through the process called physical conditioning.

If walking 30 minutes daily is too hard for you at first, try walking just an extra 10 or 20 minutes daily.  If you can do that but it’s a bit of a strain, gradually (every two weeks) increase your walking time by five minutes daily until you are up to 30 minutes.  Average walking pace is 2 mph (3.2 km/h).  Once you can comfortably handle 30 minutes daily, the next step is to increase your walking pace to 3 or 4 mph (4.8–6.4 km/h) for the entire 30 minutes.  Four mph (6.4 km/h) is definitely a brisk walk.  It’s difficult for many people to sustain over 30 minutes until they work up to it gradually.  This is often done by walking at two paces, normal and brisk, during an exercise session.  You might walk five minutes at normal pace, then five minutes briskly, alternating every five minutes until the session is over.  Every two to four weeks, you can increase the minutes of brisk pace and taper off the normal pace.  You’re able to do this easily because your level of fitness is increasing.

I’m asking you to walk briskly (3–4 mph or 4.8–6.4 km/h) for 30 minutes most days of the week.  This brisk pace burns roughly 200 calories per session, in case you’re wondering.  If you eat a 400-calorie muffin, it provides enough energy for a one-hour brisk walk.  If you don’t burn the muffin calories as exercise or basal metabolism, they’ll turn into body fat.  (But you’re not eating muffins anymore, are you?!)

If you prefer physical activity other than walking, the general rule is to start slowly and gradually increase your effort (intensity) until you’re up to about 30 minutes of moderate-intensity exercise most days of the week.  Start low, go slow.

Steve Parker, M.D.

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March 20, 2011 · 7:41 AM

Exercise, Part 8: Warnings and Precautions for Diabetics

Exercise clearly has many benefits, as discussed in prior installments of this series.  Yet we shouldn’t overlook the potential risks to diabetics either. 

Diabetic Retinopathy

Diabetics with retinopathy (an eye disease caused by diabetes) have an increased risk of retinal detachment and bleeding into the eyeball called vitreous hemorrhage. These can cause blindness. Vigorous aerobic or resistance training may increase the odds of these serious eye complications. Patients with retinopathy may not be able to safely participate. If you have any degree of retinopathy, avoid the straining and breath-holding that is so often done during weightlifting or other forms of resistance exercise. Vigorous aerobic exercise may also pose a risk. By all means, check with your ophthalmologist first. You don’t want to experiment with your eyes.

Diabetic Feet and Peripheral Neuropathy 

Diabetics are prone to foot ulcers, infections, and ingrown toenails, especially if peripheral neuropathy (numbness or loss of sensation) is present. Proper foot care, including frequent inspection, is more important than usual if a diabetic exercises with her feet. Daily inspection should include the soles and in-between the toes, looking for blisters, redness, calluses, cracks, scrapes, or breaks in the skin. See your physician or podiatrist for any abnormalities. Proper footwear is important (for example, don’t crowd your toes). Dry feet should be treated with a moisturizer regularly. In cases of severe peripheral neuropathy, non-weight-bearing exercise (e.g., swimming or cycling) may be preferable. Discuss with your physician or podiatrist.

Hypoglycemia

Low blood sugars are a risk during exercise if you take diabetic medications in the following classes: insulins, sulfonylureas, meglitinides, and possibly thiazolidinediones and bromocriptine. Hypoglycemia is very uncommon with thiazolidinediones. Bromocriptine is so new (for diabetes) that we have little experience with it; hypoglycemia is probably rare or non-existent. See drug details in chapter four. Diabetics treated with diet alone or other medications rarely have trouble with hypoglycemia during exercise.

Always check your blood sugar before an exercise session if you are at risk for hypoglycemia. Always have glucose tablets, such as Dextrotabs, available if you are at risk for hypoglycemia. Hold off on your exercise if your blood sugar is over 200 mg/dl (11.1 mmol/l) and you don’t feel well, because exercise has the potential to raise blood sugar even further early in the course of an exercise session.

As an exercise session continues, active muscles may soak up bloodstream glucose as an energy source, leaving less circulating glucose available for other tissues such as your brain. Vigorous exercise can reduce blood sugar levels below 60 mg/dl (3.33 mmol/l), although it’s rarely a problem in non-diabetics.

The degree of glucose removal from the bloodstream by exercising muscles depends on how much muscle is working, and how hard. Vigorous exercise by several large muscles will remove more glucose. Compare a long rowing race to a slow stroll around in the neighborhood. The rower is strenuously using large muscles in the legs, arms, and back. The rower will pull much more glucose out of circulation. Of course, other metabolic processes are working to put more glucose into circulation as exercising muscles remove it. Carbohydrate consumption and diabetic medications are going to affect this balance one way or the other.

If you are at risk for hypoglycemia, check your blood sugar before your exercise session. If under 90 mg/dl (5.0 mmol/l), eat a meal or chew some glucose tablets to prevent exercise-induced hypoglycemia. Re-test your blood sugar 30–60 minutes later, before you exercise, to be sure it’s over 90 mg/dl (5.0 mmol/l). The peak effect of the glucose tablets will be 30–60 minutes later. If the exercise session is long or strenuous, you may need to chew glucose tablets every 15–30 minutes. If you don’t have glucose tablets, keep a carbohydrate source with you or nearby in case you develop hypoglycemia during exercise.

Re-check your blood sugar 30–60 minutes after exercise since it may tend to go too low.

If you are at risk of hypoglycemia and performing moderately vigorous or strenuous exercise, you may need to check your blood sugar every 15–30 minutes during exercise sessions until you have established a predictable pattern. Reduce the frequency once you’re convinced that hypoglycemia won’t occur. Return to frequent blood sugar checks when your diet or exercise routine changes.

These general guidelines don’t apply across the board to each and every diabetic. Our metabolisms are all different. The best way to see what effect diet and exercise will have on your glucose levels is to monitor them with your home glucose measuring device, especially if you are new to exercise or you work out vigorously. You can pause during your exercise routine and check a glucose level, particularly if you don’t feel well. Carbohydrate or calorie restriction combined with a moderately strenuous or vigorous exercise program may necessitate a 50 percent or more reduction in your insulin, sulfonylurea, or meglitinide. Or the dosage may need to be reduced only on days of heavy workouts. Again, enlist the help of your personal physician, dietitian, diabetes nurse educator, and home glucose monitor.

Finally, insulin users should be aware that insulin injected over muscles that are about to be exercised may get faster absorption into the bloodstream. Blood sugar may then fall rapidly and too low. For example, injecting into the thigh and then going for a run may cause a more pronounced insulin effect compared to injection into the abdomen or arm.

Autonomic Neuropathy

This issue is pretty technical and pertains to function of automatic, unconscious body functions controlled by nerves. These reflexes can be abnormal, particularly in someone who’s had diabetes for many years, and are called autonomic neuropathy. Take your heart rate, for example. It’s there all the time, you don’t have to think about it. If you run to catch a bus or climb two flights of stairs, your heart rate increases automatically to supply more blood to exercising muscles. If that automatic reflex doesn’t work properly, exercise is more dangerous, possibly leading to passing out, dizziness, and poor exercise tolerance. Other automatic nerve systems control our body temperature regulation (exercise may overheat you), stomach emptying (your blood sugar may go too low), and blood pressure (it could drop too low). Only your doctor can tell for sure if you have autonomic neuropathy.

Steve Parker, M.D.

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March 6, 2011 · 2:00 AM

Exercise, Part 7: Could Exercise Hurt Me?

To protect you from injury, I recommend that you obtain “medical clearance” from a personal physician before starting an exercise program.  A physician is in the best position to determine if your plans are safe for you, thereby avoiding complications such as injury and death.  Nevertheless, most adults can start a moderate-intensity exercise program with little risk.  An example of moderate intensity would be walking briskly (3–4 mph or 4.8–6.4 km/h) for 30 minutes daily.

Men over 40 and women over 50 who anticipate a more vigorous program should consult a physician to ensure safety.  The physician may well recommend diagnostic blood work, an electrocardiogram (heart electrical tracing), and an exercise stress test (often on a treadmill).  The goal is not to generate fees for the doctor, but to find the occasional person for whom exercise will be dangerous, if not fatal.  Those who drop dead at the start of a vigorous exercise program often have an undiagnosed heart condition, such as blockages in the arteries that supply the heart muscle.  The doctor will also look for other dangerous undiagnosed “silent” conditions, such as leaky heart valves, hereditary heart conditions, aneurysms, extremely high blood pressure, and severe diabetes.

The American Diabetes Association’s Standards of Care—2011 states that routine testing of all diabetics for heart artery blockages before an exercise program is not recommended; the doctor should use judgment case-by-case.  Many diabetics (and their doctors) are unaware that they already have “silent” coronary artery disease (CAD).  CAD is defined by blocked or clogged heart arteries, which reduced the blood flow to the hard-working heart muscle.  Your heart pumps 100,000 times a day, every day, for years without rest.  CAD raises the odds of fainting, heart attack, or sudden death during strenuous exercise.  I recommend a cardiac stress test (or the equivalent) to all diabetics prior to moderate or vigorous exercise programs, particularly if over 40 years old. CAD can thus be diagnosed and treated before complications arise.  Ask your personal physician for her opinion.

Regardless of age and diabetes, other folks who may benefit from a medical consultation before starting an exercise program include those with known high blood pressure, high cholesterol, joint problems (e.g., arthritis, degenerated discs), neurologic problems, poor circulation, lung disease, or any other significant chronic medical condition.  Also be sure to check with a doctor first if you’ve been experiencing chest pains, palpitations, dizziness, fainting spells, headaches, frequent urination, or any unusual symptoms (particularly during exertion).

Physicians, physiatrists, physical therapists, and exercise physiologists can also be helpful in design of a safe, effective exercise program for those with established chronic medical conditions. 

Steve Parker, M.D.

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March 2, 2011 · 8:40 AM

Exercise, Part 6: Make It a Habit

So, I’ve convinced you that regular physical activity offers some great health benefits and you’re ready to get started. A couple weeks of intensive effort on your part, but then quitting, isn’t going to do you any good. In fact, it’s more likely to do harm (injury) than good.

The main objective at this point is to make regular physical activity a habit. Establishment of a habit requires frequent repetition over at least two or three months, regardless of the weather, whether you feel like it or not. Over time the chosen activity becomes part of your identity.

To avoid injury and burn out, begin your exercise program slowly and increase the intensity of your effort only every two or three weeks. Your body needs time to adjust to its new workload, but it will indeed adjust. Enhance your enjoyment with proper attire, equipment, and instruction, if needed. Use a portable radio or digital music system like an iPod or Zune if you tend to get bored exercising.

The “buddy system” works well for many of my patients: agree with a friend that you’ll meet regularly for walking, jogging, whatever. If you know your buddy is counting on you to show up at the park at 7 a.m., it may be just the motivation you need to get you out of bed. Others just can’t handle such regimentation and enjoy the flexibility and independence of solitary activity.

If you like to socialize, join a health club or sports team. Large cities have organized clubs that promote a wide range of physical activities. Find your niche.

Don’t be afraid to try something new. Expect some disappointment and failed experiments. Learn and grow from adversity and failure. Put a lot of thought into your choice of activity. Avoid built-in barriers. If you live in Florida you won’t have much opportunity for cross-country skiing. If joining a health club is a financial strain, walk instead. Perhaps pick different activities for cold and warm weather. Or do several types of exercise to avoid boredom.

 In summary, formation of the exercise habit requires forethought, repetition, and commitment. You must schedule time for physical activity. Make it a priority. Hundreds of my couch potato patients have done it, and I’m sure you can, too. I’ve seen 40-year-old unathletic, uncoordinated barnacles start exercising and run marathons two years later. (A marathon is 26.2 miles or 42.2 km.)

Part 7 of the series covers “medical clearance.”

Steve Parker, M.D.

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