Posted by: shericolberg | February 1, 2012

Should You Just Do Intense Exercise for Less Time?

Just when everyone was already confused about what types and amounts of training people with diabetes should be doing, along comes yet another study to muddy the waters some more. This latest exercise research was undertaken by faculty at McMaster University in Hamilton, Ontario, and appeared in the December 2011 issue of Journal of Applied Physiology (1).

The study involved eight individuals with type 2 diabetes (mean age of 63 years) who agreed to endure six sessions of high-intensity interval training done on a cycle ergometer over a two-week period. The training sessions consisted of 60 seconds of cycling done 10 times at ~90% of maximal heart rate, interspersed with 60 seconds of rest—for a total of only 10 minutes of actual exercise and 10 minutes of recovery. In other words, it involved almost an all-out sprint for a minute at a time, repeated 10 times with very little rest in between. Some call this low-volume, high-intensity interval training (HIT); others call it pure torture.

Before training and from ∼48 to 72 h after the last training bout, blood glucose responses were monitored using 24-hour continuous glucose monitoring. The exercise definitely had a positive effect on blood glucose levels: both the average levels over 24 hours and the 3-hour postprandial values after all three daily meals were improved significantly even 2-3 days after each training session, suggesting that low-volume HIT can rapidly improve glucose control and induce adaptations in skeletal muscle that improve metabolic health in people with type 2 diabetes.

While interval training is routinely used by sports teams and athletes, I have to question whether doing only this type of training would be beneficial for most individuals with diabetes. It certainly saves time—who can’t fit in 10 minutes of exercise three days per week?—but would it benefit weight control in the average person with type 2 diabetes? Probably not, as it simply doesn’t burn that many calories. Actually, it doesn’t save that much time either: when you add in the interspersed rest intervals and a warm-up and cool-down period, it still takes at least 25 minutes per session and 75 minutes per week. Current recs from the American Diabetes Association suggest that people with diabetes should try to get at least 150 minutes of moderate to vigorous exercise each week—an average of 30 minutes a day if done five days a week—so you’d only really be saving time on the two extra days you’re not doing the HIT routine.

There is no doubt that doing HIT training does have some benefits. This research suggests that doing thrice-weekly short intensive workouts may help lower blood sugar levels similarly to more frequently performed moderate activities. The sessions themselves dropped blood sugar levels from 137 mg/dL to 119 mg/dL, on average, which isn’t bad for only 10 minutes of exercise. In addition, overall and post-meal blood sugar levels were reduced long after training sessions were completed, which may or may not happen with more moderate workouts.

On the flip side, others who wrote articles about this training regimen also commented that “it requires so much suffering that you’re almost destined to quit.” Unless it’s regularly done with others, a coach, or a personal trainer to ensure motivation and positive feedback, most individuals will not have the drive to continue doing this type of training on their own long-term. What’s more, doing really intense exercise can actually cause a short-term elevation in blood glucose instead of a decrease, especially if the intense activity is not repeated enough times (such as the 10 sessions in this study) due to the effects of glucose-raising hormones released by sprinting. (So, you probably couldn’t stop early and gain the same benefits.)

If you can only do five to 10 minutes of exercise, that’s certainly better than nothing, but you really start to see the effects of exercise if you can regularly exercise harder and longer—for 20 to 30 minutes at least a few times a week. Another drawback of doing low-volume HIT is simply that not everyone is going to be able to do it, and it’s certainly not the best routine to start with when you’ve been sedentary for a while. It’s also more likely to result in overuse injuries and other joint problems that will stop you from doing anything after a while.

However, I’m totally in favor of routinely interspersing harder intervals into any regular training session—regardless of how easy or hard it is—both to increase cardiovascular fitness and to use up more blood glucose and stored carbohydrate (glycogen) in muscles, just like was done in one pilot study a few years back (2). Starting with easier workouts and interspersing slightly harder intervals into them is a lot more realistic for the majority of folks out there just getting started.

The bottom line: Just get up and off the couch to do any type of physical activity regularly, and your blood glucose levels will thank you.

References Cited:

(1) Little JP, Gillen JB, Percival ME, Safdar A, Tarnopolsky MA, Punthakee Z, Jung ME, Gibala MJ. Low-volume high-intensity interval training reduces hyperglycemia and increases muscle mitochondrial capacity in patients with type 2 diabetes. J Appl Physiol. 2006;111(6):1554-60.

(2) Johnson ST, McCargar LJ, Bell GJ, Tudor-Locke C, Harber VJ, Bell RC. Walking faster:  distilling a complex prescription for type 2 diabetes management through pedometry. Diabetes Care 2006;29:1654-5.

Posted by: shericolberg | June 8, 2011

Taking Insulin? Avoid Getting Fat!

A lot of people with type 2 diabetes delay going on insulin for as long as possible because they’ve heard horror stories about how much weight it can make them gain (or maybe they just don’t like shots), but people with type 1 don’t have a choice.  While it is true that insulin treatment is often associated with weight gain and more frequent bouts of hypoglycemia (low blood sugar), the real question is, why?

Some theories to explain insulin-induced weight gain are that when using insulin, your blood sugar is (usually) better controlled and you stop losing some of your calories (as glucose in your urine when your blood sugars exceed your urinary threshold) and that you may gain weight from having to eat extra to treat any low blood sugars caused by insulin. If you’re taking oral medications to lower your blood sugar and they are not working, however, insulin may be your main option for better control.

A few research studies have looked at whether weight gain is simply a result of eating more when you’re on insulin. One such study found that weight gain was not due to an increase in food intake, but rather that your body may increase its efficiency in using glucose and other fuels when your glycemic control improves—making you store more available energy from the foods you eat as fat (even if you’re eating the same amount as before you went on insulin) (1).  

So, what can you do to avoid weight gain if you have to take insulin?  First of all, you should try to keep your insulin doses as low as possible because the more insulin you take, the greater your potential for weight gain is.  The best way to keep your insulin needs in check is to engage in regular physical activity.  By way of example, some people with type 2 diabetes who were studied gained weight from insulin use while others did not.  Interestingly, the main difference between the “gainers” and the “non-gainers” was that the gainers were less physically active (2). Moreover, in people with type 1 diabetes, taking insulin doses that effectively manage blood sugars can also lead to weight gain, but increases in activity levels have been shown to prevent getting fatter (3).

During any physical activity, your muscles can take up blood glucose and use it as a fuel without insulin and then following exercise, your insulin action is heightened for a few hours and as long as 72 hours—meaning that you will need smaller doses of insulin to have the same glucose-lowering effect.  It is my personal experience that regular exercise is the best way to prevent insulin-induced weight gain, but your insulin doses will also need to be adjusted downward to prevent low blood sugars that cause you to take in extra calories to treat them.

Second, you may be able to avoid weight gain by taking a look at the type of insulin(s) that you are using.  For example, in overweight type 2 diabetic subjects, use of once-daily Levemir (detemir) caused less weight gain and less frequent hypoglycemia than use of NPH (4), even combined with use of rapid-acting injections of a separate insulin for meals (and the same is likely true when using Lantus, or insulin glargine).  Anyone taking basal insulin alone (once or twice daily) or following a basal-bolus regimen can benefit by making sure that insulin doses are regulated effectively to prevent blood sugar lows and highs—while using as little insulin as absolutely necessary to get the desired glycemic effect.

In other words, the type of insulin you use and the doses you take are both important to consider in the overall management of your diabetes and your body weight, regardless of which type you have. Just as importantly, though, is how you choose to manage your lifestyle, both your exercise and your dietary choices.  Changes in your lifestyle, such as cutting back on refined carbohydrates that require larger doses of insulin to cover them and exercising regularly, are likely your best bets to counteract any potential weight gain caused by insulin use.  An added side benefit is that if you have type 2 diabetes and start exercising regularly, you may actually lose fat weight and be able to lower your insulin doses more or get off of insulin injections completely.

References cited:

  1. Jacob AN et al. Weight gain in type 2 diabetes mellitus. Diabetes Obes Metab. 2007 May;9(3):386-93.
  2. Jansen HJ et al. Pronounced weight gain in insulin-treated patients with type 2 diabetes mellitus is associated with an unfavourable cardiometabolic risk profile. Neth J Med. 2010 Nov;68(11):359-66.
  3. Jacob AN et al. Potential causes of weight gain in type 1 diabetes mellitus. Diabetes Obes Metab. 2006 Jul;8(4):404-11.
  4. Fajardo Montañana C  et al. Less weight gain and hypoglycaemia with once-daily insulin detemir than NPH insulin in intensification of insulin therapy in overweight Type 2 diabetes patients: the PREDICTIVE BMI clinical trial. Diabet Med. 2008 Aug;25(8):916-23.
Posted by: shericolberg | March 25, 2011

Why Everyone Is Getting Diabetes (and Prediabetes)

The latest statistics about diabetes released by the Centers for Disease Control and Prevention are staggering: 25.8 million Americans have diabetes, and another 79 million with prediabetes are waiting in the wings to develop it. This rise in cases is exponentially greater than what was predicted even a decade ago, and the increase in diabetes a worldwide trend, not just a North American one. At current rates, everyone around the globe will have diabetes or prediabetes before the end of this century.

People are quick to point their fingers at weight gain, fast food gluttony, and slothful lifestyles as being the main culprits, but what if it’s more than that? Is there anything that can be done to abate this looming health crisis? In his recent book, Diabetes Rising, author and journalist Dan Hurley examines five potential reasons behind what has become a modern pandemic. At this point, his five hypotheses—revolving around weight gain, cow’s milk, persistent organic pollutants (POP), vitamin D, and hygiene—warrant further discussion.

The first is the Accelerator Hypothesis, which revolves around body weight and insulin resistance. Some researchers are actually beginning to believe that type 1 and type 2 diabetes–heretofore considered to be caused by autoimmune destruction of insulin-producing beta cells and a high level of insulin resistance, respectively–may actually be the same disease. He postulates that the recent rise in cases of both types of diabetes have been accelerated by weight gain (an environmental factor), but are modulated by genetic factors, including the tendency to have a highly reactive immune system and the tendency to develop insulin resistance in response to weight gain. The jury is still out on whether weight gain is a direct casual factor, but we do know that type 2 diabetes risk can be lowered greatly by even a small (5-7%) decrease in body weight.

The Cow’s Milk Hypothesis relates more directly to the development of type 1 diabetes and could more accurately be called the Foreign Protein one. In essence, early exposure in infancy to any proteins other than the ones found in human breast milk appears to make the body’s immune system more permissive toward autoimmunity and the ultimate destruction of the insulin-producing beta cells in the pancreas. An easy (and economical) approach is to promote the breast feeding of all infants as long as possible during the first year of life.

Hurley’s discussion of the risks associated with organic pollutants in the POP Hypothesis is quite compelling and is picking up steam. POPs originate from pesticides, but also from solvents, pharmaceuticals, paints, pollution, and even plastic. These compounds accumulate in body fat, so levels are higher farther up the food chain. One study actually showed a 38-fold increase in diabetes incidence when comparing the lowest and highest quartiles of POP exposure, and a follow-up study suggested that obesity leads to diabetes only when a person has POPs above a certain level—which are stored in body fat. In that case, keeping body fat lower may actually be quite effective in lowering diabetes risk by decreasing the amount of POPs stored in the body.

The Sunshine Hypothesis is not a new one where type 1 diabetes is concerned as it was noted several decades ago that its incidence is higher at northern latitudes compared to southern ones. However, the role of the sun (and vitamin D) in type 2 diabetes development (and even in prediabetes) is a more recent hypothesis. Most vitamin D is manufactured in the body following exposure to sunlight, and the rise in diabetes parallels greater use of sunscreen and less time spent outdoors. The evidence is compelling enough that recommended vitamin D intakes were recently raised for the population as a whole, based on age: 600 International Units (IU) daily for children and adults up to 70 years old, 800 IU a day for ages 71 and older.

Finally, the Hygiene Hypothesis suggests that making our environments too sterile may actually be increasing our risk of developing diabetes. In fact, people living in lesser developed regions around the world have a lower incidence of type 1 diabetes, allergies, and asthma. Exposure to some bacteria and other germs appears to strengthen the immune system and keep it less likely to start attacking parts of the body.

While these theories are interesting, what we really need to know is how to reverse the potential tsunami of diabetes cases while there is still time. Hurley postulates on “curing” diabetes with an artificial pancreas and with bariatric surgery, but neither of these solutions is really a cure, nor is either feasible on a worldwide scale.

At this point in time, the ultimate key to ending the diabetes pandemic is prevention, and that “cure” is only going to come through united action to make living healthier. Collectively, we are going to have to make personal choices to eat healthier foods and demand access to healthier (and less caloric) fare; make physical movement a requirement rather than an option (in schools and in the workplace); find government-directed ways to reduce our exposure to environmental pollutants of all types; stop oversterilizing our personal environments; and spend a little more time in the sun without overdoing the sunscreen. Furthermore, it’s likely going to take community uprisings and the use of political clout to change some of the policies in place. Time to get busy!

Posted by: shericolberg | January 18, 2011

Are Exercise-Induced Lows Making You Fat?

Over the years, I have had many exercisers with diabetes ask me why they’re gaining weight instead of losing it. There are two possible answers to that question. One answer, which is more applicable to new exercisers, is that muscle weighs more than fat (for an equivalent amount). Consequently, if you are gaining muscle while losing some fat weight due to your new exercise regimen, then your scale weight is likely not reflective of the positive changes in your body composition (i.e., less fat, more muscle).

 The second possible answer is more applicable to people who are not new to exercise, especially anyone who may have recently changed the amount or intensity of training that they’re doing. I first ask them, “Have you been treating a lot of low blood sugars recently?” When they invariably reply, “Yes,” then I know to tell them that they have simply been taking in too many extra calories while treating hypoglycemia.

Of course, you have to treat a low if you have one! However, every calorie counts, even the ones that boost your blood sugar back to normal (and beyond). People with diabetes often reach for candy, cola, juice—or other high calorie, high fat, and high sodium foods—to correct lows, which can lead to rebound high blood sugars, unhealthy eating, and weight gain. What you use to correct a low is often just extra calories not accounted for in your daily meal plan.

What can you do to avoid gaining weight when you have to treat frequent lows? The best advice is to treat them with something low in calories, but with enough glucose to bring your sugars back to normal. When you have a hypoglycemic reaction, do not binge on candy bars, cookies, and other high calorie, high fat foods. These “treats” take longer to raise your blood sugar than pure glucose and usually contain calories (like ones from fat) that do not raise blood sugar levels effectively. You are almost certain to eat too much of them waiting for your blood sugar to rise and consume unnecessary extra calories that will cause weight gain—and excess weight gain can lower the ability of your insulin to keep blood sugars in check. You can also end up with rebound hyperglycemia, which may increase your insulin needs and promote fat storage.

I’m going to sound like a walking advertisement for glucose products from here on out, but I fully understand from both professional and personal experience how critical making smart choices is when you want to keep exercising regularly and avoid weight gain. Using fast-acting glucose to raise your blood sugars is likely to contribute the fewest extra calories. Why? Pure glucose contains only 4 calories per gram, so a 15-20 gram treatment has 60-80 calories, and every single calorie goes directly to rapidly correcting your blood sugar levels.

Hypothetically speaking, if you’re correcting just two lows per week with 15 grams of carbs, you will take in an extra 6,240 calories a year, or the equivalent of almost 2 pounds of body fat (one pound of fat is 3,500 calories). By way of comparison, getting 15 grams of carbs from other foods usually results in your consumption of way more calories, especially if any of the foods contain calories coming from fat (9 calories per gram) or protein (4 calories per gram), neither of which will rapidly correct a low blood sugar.

Here are just a few other food comparisons:

  • A 2-ounce bag of Skittles candy contains almost 60 grams of carbohydrate and four times the calories of a 15-gram glucose dose. Likewise, just one ounce of Smarties contain 25 grams, which if you consumed them all would probably raise your blood sugar too much and cause you to take in extra calories.
  • A candy bar like Snickers contains about 100 extra calories for every 15 grams of carbs. Correcting lows with Snickers or other candy bars adds another 3-pound weight gain a year.
  • A regular soda that contains high-fructose corn syrup may take longer to correct a low (fructose has to be converted into glucose first),  and it’s easy to consume more than 15 grams—which is the amount in only 4 ounces of a soda (one third of a 12-ounce can).
  • Even choosing orange juice or a banana to correct a low is less effective because the fructose (fruit sugar) is much more slowly converted into glucose. You probably won’t be able to stick to only 4 ounces of juice or half of a medium banana (15 grams of carbs) while you wait for your low to be corrected, and end up consuming more calories than necessary.

 Check out some calorie intake comparisons using Dex4′s new Hypo Smart Choice Calculator, at http://dex4.com/smartchoice. You’ll likely be surprised how many extra calories you may be consuming just treating low blood sugars with the usual things like orange juice and soda!

There is nothing worse than exercising and trying to lose weight, but ending up gaining some instead due to all the extra calories you eat to correct low blood sugars. If you can prevent lows with diet and medication changes before, during, and after exercise and avoid taking in those extra calories in the first place, certainly do that!  But when you do have to treat an occasional low, keep in mind that using food rather than pure glucose can add a lot of calories to your total yearly intake and your lows may take longer to correct.

In short, pure glucose is always best for rapid treatment of lows, although pure sucrose (table sugar, as found in hard candies) is second best. For prevention of lows during longer bouts of exercise or overnight, however, consider taking in a low-calorie bedtime snack with a balance of carbs, protein, and fat that will keep your blood sugars stable for longer. Some examples are Balance bars, low-fat and reduced sugar yogurt, or low-calorie ice cream. An ounce of prevention is always worth a pound of cure, especially if a hypoglycemic episode leads you to eat everything in sight!

Posted by: shericolberg | December 17, 2010

Exercise can help tame type 2 diabetes, say new guidelines

ACSM, American Diabetes Association guidelines make strong case for physical activity

INDIANAPOLIS – New guidelines on exercise for people with diabetes are likely to open some eyes—and, for those who follow them, help prevent or manage diabetes, improve overall health and boost quality of life. A panel of nine experts developed the recommendations, published this month in Medicine & Science in Sports & Exercise®, the official journal of the American College of Sports Medicine (ACSM). ACSM and the American Diabetes Association issued the guidelines as a Joint Position Statement.

While research has solidly established the importance of physical activity to health for all individuals, the new guidelines provide specific advice for those whose diabetes may limit vigorous exercise. The recommendations call for at least 150 minutes a week of moderate-to-vigorous aerobic exercise spread out at least three days during the week, with no more than two consecutive days between bouts of aerobic activity. “Most people with type 2 diabetes do not have sufficient aerobic capacity to undertake sustained vigorous activity for that weekly duration, and they may have orthopedic or other health limitations,” says Sheri R. Colberg, Ph.D., FACSM, who chaired the writing group. Hence, she explains, the group calls for a regimen of moderate-to-vigorous activity and makes no recommendation for a lesser amount of vigorous activity.

Strength training, too
Aerobic activity alone cannot give full benefit of exercise to diabetic individuals, say the experts. Recent research has shown that resistance exercise (strength training) is as important as—and perhaps even more important than—aerobic training in diabetes management. The latest studies, says Colberg, have reinforced the additional benefit of combining aerobic and resistance training for people with diabetes.

No excuses: Physicians should prescribe exercise
According to Colberg, “Many physicians appear unwilling or cautious about prescribing exercise to individuals with type 2 diabetes for a variety of reasons, such as excessive body weight or the presence of health-related complications. However, the majority of people with type 2 diabetes can exercise safely, as long as certain precautions are taken. The presence of diabetes complications should not be used as an excuse to avoid participation in physical activity.” In keeping with the philosophy of ACSM’s Exercise is Medicine® initiative, Colberg urges that physical activity be a conscious part of every person’s health plan, as appropriate for age and physical condition.

High stakes, high yield
The benefits far exceed considerations of an individual’s health and quality of life, say Colberg and other experts. Predictions that one in three Americans will have diabetes by 2050 (Centers for Disease Control and Prevention) are accompanied by estimates that diabetes and prediabetes in the U.S. will cost almost $500 billion a year by 2020 (UnitedHealth Group, Inc.). According to Colberg, “If current trends go unabated, we are in fact doomed to higher health care costs and drastically reduced quality and length of life due to diabetes-related complications such as heart disease and kidney failure. As individuals, as communities and as part of a nation and world, we have to work collectively to stop diabetes before it stops us.”

Posted by: shericolberg | October 21, 2010

Announcing “Fit Brain, Fit Body!” Programs

Announcing the “Fit Brain, Fit Body!” Fitness/Lifestyle Programs from the Lifelong Exercise Institute

What makes the LEI “Fit Brain, Fit Body!” Programs different (and better) than any exercise programs or weight loss plans you’ve tried before? Here are just a few (key) differences:

  • Daily physical movement that doesn’t require sweating 
  • No dieting–ever! Just easy-to-implement nutrition tips Read More…
  • Posted by: shericolberg | October 15, 2010

    Why Sitting May Be Deadly

    Not that you need anything else to worry about, but now experts are claiming that sitting can kill you. We all know the dangers of a sedentary lifestyle, but this latest news is more alarming Read More…

    Posted by: shericolberg | October 8, 2010

    Would You Like Some Vinegar with That?

    Although previous studies show that vinegar improves insulin sensitivity in healthy or insulin-resistant subjects, information on the effect of vinegar in people with type 1 diabetes has been lacking—until now. A study Read More…

    A study published this spring in Journal of Applied Physiology looked at whether what you eat right after exercise can impact your metabolic responses and for how long afterwards—but with a twist. Read More…

    Posted by: shericolberg | March 8, 2010

    5 FREE Healthy Living Reports (via e-mail)

    Get Expert Healthy Living Reports–FREE!!

    Give us just 15 minutes per week and our fitness and healthy living experts will give you invaluable advice based on their years of training…Free! From physical activity myths demystified, to easy weight loss tips, to eating healthy on a budget, to core training exercises, and real age tests, we will provide you with access to 5 FREE Healthy Living reports offered by the Lifelong Exercise Institute. Read More…

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