Analysis Shows Value of Structured Exercise Programs in Diabetes Care

Insurance Benefits for Exercise Programs Can Cut Health Costs

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FOR the person with type 2 diabetes, or the high-risk individual who is trying to prevent the development of diabetes, there is an enormous body of research literature documenting the benefits of exercise. Indeed, research shows that just six weeks of exercise is enough to change both brain chemistry and body chemistry for the better; diets alone don’t have the same effect. But some questions still remain ‒ how much exercise is needed, and what kind?

A host of studies have linked exercise programs with improved health measures related to blood pressure, lipid levels — including cholesterol and triglycerides — cardiovascular events, cognition, physical performance, premature death and quality of life. Analyses of interventions to promote physical exercise in adults have found that compared with no intervention, exercise programs are cost-effective and have the potential to improve survival rates and health-related quality of life.

A recent systematic review and meta-analysis ‒ undertaken by scientists led by Daniel Umpierre of the Hospital de Clinica de Porto Alegre in Brazil ‒ compares the association between physical activity advice and structured exercise programs, respectively, and markers of diabetes. It reveals that implementing structured exercise training — including aerobic, resistance or both — is associated with a greater reduction in HbA1c levels for patients with diabetes compared to patients in control groups. Results of the study are published in the May 4 issue of the Journal of the American Medical Association (JAMA).

A structured exercise is a task, activity, or question posed by a leader that pushes everyone to reflect, focus, offer ideas and insights, and become engaged in learning. Structured exercises offer group leaders a variety of options for encouraging group participation and discussion, practicing skills, and involving adults who have a range of learning styles and capabilities.

After analyzing the results of 47 randomized clinical trials, the researchers also found that exercising for longer periods of time was better at bringing blood sugar levels down than exercising more intensively. Longer weekly exercise duration was also associated with a greater decrease in these levels, according to results of the analysis of previous studies.

The meta-analysis shows that greatest reductions in HbA1c occurred in patients exercising for more than 150 minutes in total per week. Exercise intensity did not appear to matter. Exercising a minimum of 150 minutes a week (usually broken down to 30 minutes of exercise five days a week) is recommended by such institutions as the American College of Sports Medicine.

"People with type 2 diabetes should engage in regular exercise training, preferentially supervised exercise training," says Beatriz Schaan, the study's senior author. "If these patients can perform training for more than 150 minutes per week, this would be more beneficial concerning their glucose control. However, if they cannot reach this amount of weekly exercise, lower exercise amounts are also beneficial."

The Importance of Exercise in Diabetes Management

A recent joint statement from the American Diabetes Association (ADA) and the American College of Sports Medicine (ACSM) has already underscored the importance of physical exercise to prevent and manage insulin resistance, type 2 diabetes mellitus, gestational diabetes mellitus, and the complications of diabetes.

“Current guidelines recommend that patients with type 2 diabetes should perform at least 150 minutes per week of moderate-intensity aerobic exercise and should perform resistance exercise three times per week,” the authors of the Brazil study wrote. “Regular exercise improves glucose control in diabetes, but the association of different exercise training interventions on glucose control is unclear.”

Indeed, although some clinical trial evidence suggests that aerobic exercise and resistance training can each improve glucose control in patients with type 2 diabetes mellitus, not all clinical trials are consistent with regard to this finding.

However, differences in results of clinical trials about the ability of aerobic exercise and resistance training to improve glucose control are primarily due to differences in trial design, including modality, intensity, exercise program duration, adherence to the programs, sample size, and patient populations.

In the Brazilian study, the authors analyzed 47 randomized controlled trials (RCTs) into the effect of exercise on HbA1c, with a total of 8538 patients. In 23 of these RCTs, patients took part in structured exercise training, and in the other 24 they were simply given advice on physical activity.

Across all studies analyzed, engaging in structured exercise was associated with decreased HbA1c levels compared with controls, whether this was structured resistance training (fall in HbA1c of 0.57%), structured aerobic exercise (fall of 0.75%), or a combination of both (0.51% fall).

A longer total time spent in structured exercise was associated with better glycemic control. If total weekly time in structured exercise exceeded 150 minutes, the average drop in HbA1c was 0.89%, against 0.36% for a time of 150 minutes or less.

Physical activity advice was only associated with a decline in HbA1c if it was combined with dietary advice.

The authors said: “This systematic review and meta-analysis of RCTs demonstrates important findings regarding the prescription of structured exercise training. First, aerobic, resistance, and combined training are each associated with HbA1c decreases, and the magnitude of this reduction is similar across the three exercise modalities.

“Second … structured exercise of more than 150 minutes per week is associated with greater declines in HbA1c than structured exercise of 150 minutes or less per week in patients with type 2 diabetes. This finding is important because the current guideline-recommended exercise duration is at least 150 minutes per week.

They added: “Although high-intensity exercise has been previously shown to have an association with HbA1c reduction, our findings did not demonstrate that more intensive exercise was associated with greater declines in HbA1c.”

In an accompanying editorial, Marco Pahor, director of the University of Florida Institute on Aging, argues that “the meta-analysis … and cumulative evidence from a large number of randomized controlled trials conducted over the past few decades in the area of physical activity and exercise provide solid evidence for public policy makers to consider structured exercise and physical activity programs as worthy of insurance reimbursement to promote health, especially in high-risk populations.”

Insurance Benefits for Exercise Programs Can Cut Health Costs
With respect to type 2 diabetes, Medicare reimburses for approved self-management education and medical nutrition therapy programs. But no specific reimbursement is given for any physical activity or exercise program, despite evidence that such programs can help improve health and cut costs.

Questions remain as to what format reimbursable exercise and physical activity programs should take, what population group should be targeted, and at what stage of life or health status would a lifestyle intervention be most cost-effective to implement.

Some insurance providers already include a fitness benefit for members, such as monthly membership at certain fitness centers or access to personal trainers or exercise classes at reduced cost. Indeed, use of such health plan-sponsored club benefits by older adults has been linked to slower increases in total health care costs.

In one study, older adults who visited a health club two or more times a week over two years incurred $1,252 less in health-care costs in the second year than those who visited a health club less than once a week. Programs among people with lower incomes can also pay off, because people in that group are otherwise more likely to forego health-promoting physical activity because of economic constraints or safety concerns.

“People are willing to invest in improved health, but if you have a fixed amount of resources then you want to choose where you get the most health for the dollar,” said Erik Groessl, an assistant professor of family and preventive medicine at the University of California, San Diego, and director of the UCSD Health Services Research Center. Groessl was not involved in the current analysis.

Group training or walking programs, for example, can be cost-effective, sustainable forms of physical activity that don’t require expensive health care professionals or equipment. But more costly interventions that yield dramatic results might also be worth the expense.

“There is a lot of evidence that physical activity works, and I think it’s time to start putting it into practice more widely,” Groessl said.

Sources: JAMA, University of Florida News, Medpage Today

Diabetes: The Importance of Exercise in Diabetes Management

Just Six Weeks of Exercise Is Enough to Change Both Brain Chemistry and Body Chemistry for the Better; Diets Alone Don't Have the Same Effect

FOR the person with type 2 diabetes, or the high-risk individual who is trying to prevent the development of diabetes, there is an enormous body of research literature documenting the benefits of exercise. Unfortunately, there is little data on how to motivate patients to maintain a long term healthy regimen.

Research currently being carried out by scientists at the University of Colorado's School of Medicine is investigating why exercise feels more difficult for people suffering from type 2 diabetes than it does for people without the disease.

With a recent study showing that under half of all American (and also in other parts of the world, according to anecdotal evidence) with type 2 diabetes take any regular exercise, and that people who do not have diabetes are actually more likely to take exercise, the team hope to pinpoint the reasons why this is.

If this study is able to confirm findings from previous research that revealed that exercise felt harder for those people with diabetes, then it is hoped it will be possible to design specific exercise programs for people with type 2 diabetes.

Indeed, when you can't move much without discomfort, do-ability is the key to enjoying a workout. Body size is a major factor that is often overlooked. Big-made people can't do 'normal' fitness activities like biking and rowing and weight machines because they're too uncomfortable. Their bodies get in the way. They can't bend over, they don't fit, they can't run, either — the impact hurts their joints. So they give up on exercise before even trying.

Finding a doable exercise is crucial for obese people because movement is often the key that locks in weight loss. Diets come and go, but exercise sticks, and it prompts the lifestyle changes necessary to shed pound and keep them off, according to Dr.James A. Levine, a Mayo Clinic expert on nutrition and endocrinology.

"There are psychological and chemical advantages of moving over eating," Levine says. "A diet is a restriction — by definition unpleasant, to be avoided. But when you move it is something you have done and achieved. Every time you do it, you are winning, and feel good about yourself and want to do it again. You not only burn lots of calories, but may be motivated to make better food decisions."

Research is finding that just six weeks of exercise is enough to change both brain chemistry and body chemistry for the better, he adds. Diets alone don't have the same effect.

Exercise feeds on itself — once you get moving you might not want to stop. It is essential that all people hoping to slim down find some kind of exercise they can look forward to every day. Options that fit the largest bodies can be surprisingly fun, including walking, water running, swimming, and elliptical training (on wheels or in a gym).

Obese or not, physical exercise is important for all of us. Physical conditioning is one of the most important quality of life factors that we can actually improve, thus contributing to a longer and healthier life. Even better, exercise is empowering since each person can control the amount of activity they do to achieve the maximum benefit.

What are the benefits of exercise in people with type 2 diabetes?
A major benefit of exercise is its effect on the heart and the associated reduction in death from heart disease. In addition to lowering the risk of heart disease in type 2 diabetes, exercise helps to decrease the chances of developing diabetes. This can be especially important for those with pre-diabetes.

In one study, the risk of developing diabetes was reduced by 24% (based on an energy expenditure of 2000 calories per week through exercise). This protective effect of exercise was seen the most in the group at highest risk for developing type 2 diabetes.

The mechanism for this benefit is that exercising muscles are more sensitive to circulating insulin. They thus take up blood sugar more easily and use sugar more effectively. Research has shown that even short term aerobic exercise improves the sensitivity of muscles to insulin.

There is a strong association between diabetes and the location of fat in the body. It has been known for a long time that people with increased internal belly fat (the classic apple-shaped person with a round belly versus the pear-shaped person with a heavier deposit of fat around the hips and thighs) have a higher risk for insulin resistance, high cholesterol, and high blood pressure.

This triad of diseases is part of a disorder called ‘Syndrome X’. Interestingly, in some patients who are not overweight by definition, internal belly fat may still be high, as visualized with special imaging tests of the abdomen.

For example, a classic apple-shaped obese person is a Sumo wrestler. However, Sumo wrestlers are physically active and actually have low internal belly fat stores. Therefore, they are rarely afflicted with blood sugar or cholesterol problems!

In addition to its benefits on muscle insulin sensitivity, aerobic exercise also improves blood cholesterol levels and blood pressure control. This benefit occurs regardless of weight loss. In one study, patients with type 2 diabetes on a 3-month exercise program reduced their triglyceride levels by 20%, increased their good cholesterol (HDL) by 23%, and decreased their blood pressure to better levels too!

The benefits of exercise in patients with diabetes, and in those at high-risk for developing type 2 diabetes (and those with Syndrome X), may include the following:

• Reduced heart disease

• Prevention of diabetes in those at high risk

• Improved muscle sensitivity to insulin

• Better blood sugar control

• Better blood cholesterol profiles

• Better blood pressure control

• Potential weight loss

• Improved general sense of well being

Though exercise is an important part of managing diabetes in general, like everything else it's not quite black and white. In certain situations, patients with diabetes should approach any exercise regimen with caution.

Additionally, exercise may need to be avoided, at least temporarily, in some patients. And there are a few specific concerns regarding diabetes and exercise that every diabetic trying to maintain a healthy lifestyle should be aware.

Hypoglycemia
Hypoglycemia is a condition that occurs when blood sugars fall to excessively low ranges (usually less than 60mg/dl). With hypoglycemia, patients experience confusion, sweating, shakiness, and in severe cases, coma and seizure.

Note: Exercise can induce hypoglycemia, particularly in patients who are taking insulin, although patients on oral agents are also at risk. In part, this decrease in blood sugar results from an increase in the muscles' use of glucose and because the liver's production of glucose is impaired.

Studies have shown that patients taking insulin who reduced the dose of their short-acting insulin by 33-50% before exercising were able to prevent the onset of exercise-related hypoglycemia. While hypoglycemia can occur during or directly after activity, it can also occur 6-12 hours after exercise. Caution is therefore recommended during this period as well.

For patients who exercise regularly and need insulin therapy, an insulin pump is a great option for delivery. The pump provides a constant infusion of insulin that can be adjusted and allows for an extra amount to cover meals. With the aid of a doctor or nurse trained in pump therapy, the dosing can be adjusted to fit exercise regimens.

The only activities for which the pump may not be well suited are swimming and sports involving vigorous movements. These activities can dislodge the cannula, the tube through which the insulin is infused into the body.

Some strategies to avoid hypoglycemia are listed below:

• Measure blood sugars before, during, and after exercise.

• For planned exercise, if you are on insulin, reduce the short-acting insulin by 33 to 50%.

• For unplanned exercise, take 30 to 20g of carbohydrates extra for each 30 minutes of exercise.

• Avoid injecting insulin into the arms and legs and use the abdomen because the insulin will be absorbed more evenly.

• If you exercise in the evening, you may need to add a snack before bedtime to make certain your sugars don't go too low at night.

Diabetes, Exercise & Small Blood Vessel Disease
Patients with diabetes often have eye disease, whether they have symptoms or not. The eye disease associated with diabetes results from the formation of small, fragile, easily breakable blood vessels in the retina at the back of the eye. When these vessels break, bleeding in the back of the eye occurs. Continued damage can result in loss of vision.

In patients with extensive eye disease related to diabetes (diabetic retinopathy), the intensity and type of exercise may need to be limited. Activities that should be avoided include excessive straining (as in weightlifting), excessively jarring activities (such as boxing), and exercise that involves severe pressure changes (like diving). If there is early eye disease and no new vessel formation, no limitations are necessary. If kidney disease is present, the only precaution is avoiding exercise that can raise blood pressure.

Diabetes, Exercise & Large Blood Vessel Disease
Large blood vessels, such as those that normally supply blood and oxygen to the heart, can also be affected by diabetes. A careful medical history and examination are needed in all diabetic patients who have heart disease before they commit to an exercise program. From a recent Consensus Development Conference on the diagnosis of Coronary Heart Disease in people with Diabetes, the American Diabetes Association has published recommendations for exercise stress testing in diabetes patients. Stress testing should be done before embarking on an exercise program.

The recommendations of the American Diabetes Association for testing are listed below:

• Any patient with cardiac symptoms.

• Abnormal resting EKG.

• Peripheral or carotid artery disease.

• Sedentary lifestyle, age > (greater than) 35 years, and plans to begin a vigorous exercise program.

• Two or more of the following risk factors in addition to diabetes:

• Total cholesterol > 240mg/dl, LDL.160mg/dl, or HDL <35mg/dl;

• Blood pressure > 140/90;

• Smoking;

• Family history of premature heart disease; and

• Kidney involvement from diabetes.

What does this mean for you?
Before starting on any exercise program, a thorough examination and medical history should be performed by your doctor. Patients who have diabetes should pay particular attention to blood vessel complications.

Another important area to discuss is the estimated calorie expenditure and strategies to lessen the risk of hypoglycemia. Food intake ‒ both before and after exercise ‒ should be reviewed.

Approximately 50% of the calories burned during exercise come from a carbohydrate source (with the remainder coming from fat). You can thus calculate that in a 30 minute exercise session, wherein an activity like cycling at 13 kmph burns about 10 cal/min, a person would need to consume about 38g of carbohydrates (50% of 300kcal =150 kcal or 37.5 g of carbohydrate).

We know this because each gram of carbohydrate is 4 kcal, and 150 divided by 4 is 37.5. These calculations, while a little confusing at first, can be a really valuable tool with some practice and guidance.

Regarding aerobic activity, training sessions should begin slowly. Allow 8 to 12 weeks to reach a desired training level. At a minimum, three to four 20 to 30 min sessions are needed to see a benefit. To estimate your predicted maximal heart rate: take 220 and subtract your age in years. You should be working at about 60 to 70% of this maximum rate to ensure a safe, effective workout.

For example, if you are 40 years old, calculate as follows: 220 - 40 =180 and 70% of 180 = 126. This means your heart rate should be up to 126 beats per minute. It is also important to remember to add a warm up and cool down period to your workout to help prevent injury.

In addition to the above information, the American Diabetes Association has made the following recommendations for exercising:

• Carry an ID card and wear a bracelet that identifies you as having diabetes.

• Be alert for signs of hypoglycemia during and after exercise.

• Drink plenty of fluids before, during, and after exercise.

• Measure blood sugar levels and act if the reading is less than 80mg/dl or greater than 240mg/dl.

If you need more specific information, the American Diabetes Association website is a great resource and the International Diabetic Athletes Association has additional information.

Once again, discuss any question or concerns you may have with your physician before starting any activity program. When done safely, there is no doubt that the benefits of exercise in patients with diabetes far outweigh the risks.

With inputs from MedicineNet.com

Why Do Diabetics Find It Difficult To Exercise, Researchers Wonder

Research being carried out by scientists at the University of Colorado School of Medicine is investigating why exercise feels more difficult for people suffering from type 2 diabetes than it does for people without the disease.

With a recent study showing that under half of all people with type 2 diabetes take any regular exercise, and that people who do not have diabetes are actually more likely to take exercise, the team hope to pinpoint the reasons why this is.

The new study is examining 50 women aged between 50 and 75, with each being questioned about their level of comfort with exercise, and the findings for those with diabetes being compared to that of women without the disease of a similar age, weight and physical ability.

If this study is able to confirm findings from previous research that revealed that exercise felt harder for those people with diabetes, then it is hoped it will be possible to design specific exercise programmes for people with type 2 diabetes.

New Study Finds New Connection Between Yoga and Mood

Researchers from Boston University School of Medicine (BUSM) have found that yoga may be superior to other forms of exercise in its positive effect on mood and anxiety. The findings, which currently appear on-line at Journal of Alternative and Complementary Medicine, is the first to demonstrate an association between yoga postures, increased GABA levels and decreased anxiety.

The researchers set out to contrast the brain gamma-aminobutyric (GABA) levels of yoga subjects with those of participants who spent time walking. Low GABA levels are associated with depression and other widespread anxiety disorders.

The researchers followed two randomized groups of healthy individuals over a 12-week long period. One group practiced yoga three times a week for one hour, while the remaining subjects walked for the same period of time. Using magnetic resonance spectroscopic (MRS) imaging, the participants' brains were scanned before the study began. At week 12, the researchers compared the GABA levels of both groups before and after their final 60-minute session.

Each subject was also asked to assess his or her psychological state at several points throughout the study, and those who practiced yoga reported a more significant decrease in anxiety and greater improvements in mood than those who walked. "Over time, positive changes in these reports were associated with climbing GABA levels," said lead author Chris Streeter, MD, an associate professor of psychiatry and neurology at BUSM.

According to Streeter, this promising research warrants further study of the relationship between yoga and mood, and suggests that the practice of yoga be considered as a potential therapy for certain mental disorders.