Diabetes and Exercise

Two recent European studies yielded some striking results related to the benefits of exercise to people with diabetes.

A study of the physical activity patterns over a five year period of more than 15,000 individuals pulled from the Swedish national Diabetes Register found that those who were categorized in a “regular exercise” group (more than three times per week) were significantly less likely to have a cardiovascular event or to die either from cardiovascular disease or any other cause. More significant still, individuals who were initially grouped in a “low physical activity” (exercise once or less often each week) but moved to the “regular exercise” group during the course of the study showed a 67% reduction is cardiovascular events, CV related death, or death from any cause in comparison to subjects who remained inactive.

A group from the German Institute of Human Nutrition determined, through both a prospective study and analysis of 12 other studies, found that higher levels of “total physical activity”, “leisure time physical activity” and “walking” significantly reduced the risk of death in people with diabetes. Leisure time physical activity included gardening, cycling and household work, for instance.

Both studies pointed out that people with diabetes are less likely to be physically active than the general population, but the Swedish study emphasized that “it’s never too late” to gain benefit from becoming more active.Two recent European studies yielded some striking results related to the benefits of exercise to people with diabetes.

A study of the physical activity patterns over a five year period of more than 15,000 individuals pulled from the Swedish national Diabetes Register found that those who were categorized in a “regular exercise” group (more than three times per week) were significantly less likely to have a cardiovascular event or to die either from cardiovascular disease or any other cause. More significant still, individuals who were initially grouped in a “low physical activity” (exercise once or less often each week) but moved to the “regular exercise” group during the course of the study showed a 67% reduction is cardiovascular events, CV related death, or death from any cause in comparison to subjects who remained inactive.

A group from the German Institute of Human Nutrition determined, through both a prospective study and analysis of 12 other studies, found that higher levels of “total physical activity”, “leisure time physical activity” and “walking” significantly reduced the risk of death in people with diabetes. Leisure time physical activity included gardening, cycling and household work, for instance.

Both studies pointed out that people with diabetes are less likely to be physically active than the general population, but the Swedish study emphasized that “it’s never too late” to gain benefit from becoming more active.

A study conducted by Dr.  Sabyasachi Sen (Baystate Medical Center in Springfield, Mass.) and colleagues found that people with prediabetes had developed similar dysfunction of small blood vessels as people with “full blown” diabetes. However, a structured aerobic exercise program over a six week period improved “vascular reactivity” to near normal levels even without weight loss. Vascular reactivity is, in essence, the flexibility of an artery to expand as blood flows through.

The improvement seen in the participants with prediabetes was significantly greater than similar studies of people with diabetes, where vascular reactivity regained only about one half its normal state.

And, while the participants in this study did not show weight loss or improvements in blood pressure, there was a significant drop in cholesterol levels and inflammation markers, both risk factors for heart disease.

These results suggest not only that exercise is crucial in reducing diabetes-related risk for heart disease, but also that early intervention in the prediabetes state may be much more effective in preserving cardiovascular health.A study conducted by Dr.  Sabyasachi Sen (Baystate Medical Center in Springfield, Mass.) and colleagues found that people with prediabetes had developed similar dysfunction of small blood vessels as people with “full blown” diabetes. However, a structured aerobic exercise program over a six week period improved “vascular reactivity” to near normal levels even without weight loss. Vascular reactivity is, in essence, the flexibility of an artery to expand as blood flows through.

The improvement seen in the participants with prediabetes was significantly greater than similar studies of people with diabetes, where vascular reactivity regained only about one half its normal state.

And, while the participants in this study did not show weight loss or improvements in blood pressure, there was a significant drop in cholesterol levels and inflammation markers, both risk factors for heart disease.

These results suggest not only that exercise is crucial in reducing diabetes-related risk for heart disease, but also that early intervention in the prediabetes state may be much more effective in preserving cardiovascular health.

Researchers at Duke University compared different combinations of exercise among almost 200 overweight and sedentary adults aged 18 to 70, and observed how different exercise regimens affected fat that surrounds internal organs. This abdominal “visceral fat”, has been associated with an increased risk of heart disease, type 2 diabetes, and even some cancers.

Of particular note was the difference over the eight month study between aerobic exercise (jogging) and resistance exercise (weight lifting) when it came to calorie burning and the reduction of visceral fat. The aerobic group jogged 12 miles per week and the resistance group worked out three times per week.

Aerobic exercise significantly reduced visceral fat among that group (and among a group that practiced both aerobic and resistance training), and improved risk factors for heart disease and diabetes such as insulin resistance and blood triglyceride levels. Resistance training alone did not achieve the same results.

Researchers reported that aerobic exercise burned 67% more calories than resistance trainingResearchers at Duke University compared different combinations of exercise among almost 200 overweight and sedentary adults aged 18 to 70, and observed how different exercise regimens affected fat that surrounds internal organs. This abdominal “visceral fat”, has been associated with an increased risk of heart disease, type 2 diabetes, and even some cancers.

Of particular note was the difference over the eight month study between aerobic exercise (jogging) and resistance exercise (weight lifting) when it came to calorie burning and the reduction of visceral fat. The aerobic group jogged 12 miles per week and the resistance group worked out three times per week.

Aerobic exercise significantly reduced visceral fat among that group (and among a group that practiced both aerobic and resistance training), and improved risk factors for heart disease and diabetes such as insulin resistance and blood triglyceride levels. Resistance training alone did not achieve the same results.

Researchers reported that aerobic exercise burned 67% more calories than resistance training

A study conducted at Queen’s University in Kingston equipped 135 obese, inactive volunteers with small, hip-mounted accelerometers around the clock for a week. The less active one third of the group recorded just six minutes of moderate activity throughout each day. A middle third recorded an average of 17 minutes. The most active third accumulated a total of 34 minutes per day of moderate activity.

When researchers analyzed the activity patterns, adding up the total amount of sporadic “light” and “moderate” movements in one-minute sections, they found that the most-active group was significantly fitter than the least active group, by an amount corresponding to a 13-per-cent reduction in risk of death from all causes and a 15-per-cent reduction in risk of heart disease. This was despite the fact that none of the subjects did any “exercise” that met a “customary” 10-minute minimum threshold. That threshold had been the position of the American College of Sports Medicine’s 1998 official position.

Last month, a panel released an updated ACSM position to replace the 1998 document. Their discussion of the minimum threshold reflects a more nuanced understanding of the needs of different people:

“Durations of exercise [less than] 10 minutes may result in fitness and health benefits, particularly in sedentary individuals,” they wrote. “However, the data are sparse and inconclusive.”

While this study seemed to confirm that position, the researchers point out that even the most active subjects in this study were still obese and at an elevated risk of a wide variety of health problems. And, that while accumulating two minutes of physical activity here and three minutes there can make a real difference to their health, this modest level of activity is not as beneficial as hitting the standard recommendation of 30 minutes of moderate exercise five times a week.A study conducted at Queen’s University in Kingston equipped 135 obese, inactive volunteers with small, hip-mounted accelerometers around the clock for a week. The less active one third of the group recorded just six minutes of moderate activity throughout each day. A middle third recorded an average of 17 minutes. The most active third accumulated a total of 34 minutes per day of moderate activity.

When researchers analyzed the activity patterns, adding up the total amount of sporadic “light” and “moderate” movements in one-minute sections, they found that the most-active group was significantly fitter than the least active group, by an amount corresponding to a 13-per-cent reduction in risk of death from all causes and a 15-per-cent reduction in risk of heart disease. This was despite the fact that none of the subjects did any “exercise” that met a “customary” 10-minute minimum threshold. That threshold had been the position of the American College of Sports Medicine’s 1998 official position.

Last month, a panel released an updated ACSM position to replace the 1998 document. Their discussion of the minimum threshold reflects a more nuanced understanding of the needs of different people:

“Durations of exercise [less than] 10 minutes may result in fitness and health benefits, particularly in sedentary individuals,” they wrote. “However, the data are sparse and inconclusive.”

While this study seemed to confirm that position, the researchers point out that even the most active subjects in this study were still obese and at an elevated risk of a wide variety of health problems. And, that while accumulating two minutes of physical activity here and three minutes there can make a real difference to their health, this modest level of activity is not as beneficial as hitting the standard recommendation of 30 minutes of moderate exercise five times a week.

A presentation at the annual meeting of the American College of Sports Medicine and the Second World Congress on Exercise is Medicine suggests that early morning exercise is more beneficial to blood pressure and to getting a good night’s sleep than a workout at 1 PM or 7 PM. Appalachian State University’s Dr. Scott Collier and student research assistants Kimberly Fairbrother and Ben Cartner had research volunteers between the ages of 40 and 60 walking on a treadmill for 30 minutes, three times a week.

Tracking blood pressure and sleep patterns of the volunteers revealed that the early morning group saw a 10% reduction in blood pressure, which lasted throughout the day. Additionally, that group’s blood pressure dropped an average of 25% at night, and they slept longer and had more beneficial sleep cycles. These benefits were not observed in the mid-day or early evening groups.

“We know a rush of hormones is released when a person first awakens in the morning that raises blood pressure,” Collier commented. “Our blood pressure dips at night which helps reset the body, keeping blood pressure within a certain range and relaxing vasculature and the heart. We know the long-term clinical manifestations of poor sleep include hypertension and myocardial infarction or heart attacks. Also, obesity and diabetes can be related to poor sleep. We wanted to know if there could be a best benefit of exercise related to improved blood pressure.” However, Dr. Collier had expected to see the greatest benefits to the 7 PM exercise group.

Collier next will study individuals who exercise at different times of the day to determine if changes in hormone secretion are impacting their blood pressure levels.A presentation at the annual meeting of the American College of Sports Medicine and the Second World Congress on Exercise is Medicine suggests that early morning exercise is more beneficial to blood pressure and to getting a good night’s sleep than a workout at 1 PM or 7 PM. Appalachian State University’s Dr. Scott Collier and student research assistants Kimberly Fairbrother and Ben Cartner had research volunteers between the ages of 40 and 60 walking on a treadmill for 30 minutes, three times a week.

Tracking blood pressure and sleep patterns of the volunteers revealed that the early morning group saw a 10% reduction in blood pressure, which lasted throughout the day. Additionally, that group’s blood pressure dropped an average of 25% at night, and they slept longer and had more beneficial sleep cycles. These benefits were not observed in the mid-day or early evening groups.

“We know a rush of hormones is released when a person first awakens in the morning that raises blood pressure,” Collier commented. “Our blood pressure dips at night which helps reset the body, keeping blood pressure within a certain range and relaxing vasculature and the heart. We know the long-term clinical manifestations of poor sleep include hypertension and myocardial infarction or heart attacks. Also, obesity and diabetes can be related to poor sleep. We wanted to know if there could be a best benefit of exercise related to improved blood pressure.” However, Dr. Collier had expected to see the greatest benefits to the 7 PM exercise group.

Collier next will study individuals who exercise at different times of the day to determine if changes in hormone secretion are impacting their blood pressure levels.

People with type 2 diabetes can make a significant improvement to their glucose control by getting just over 20 minutes of exercise a day.

In a new summary of the research, doctors pooled the data on exercise to get a better overall picture. The results were encouraging. Taking part in any exercise program that lasted at least 12 weeks improved glucose control.

Aerobic exercise worked best, but resistance exercise (such as using weights) also worked well. More important than the type of exercise was the amount. Those people who exercised for at least two and a half hours a week (just over 20 minutes a day) showed the most impressive results.

The researchers said that the improvement in glucose control was about what you might see if you added a second glucose-control drug to someone’s medication.People with type 2 diabetes can make a significant improvement to their glucose control by getting just over 20 minutes of exercise a day.

In a new summary of the research, doctors pooled the data on exercise to get a better overall picture. The results were encouraging. Taking part in any exercise program that lasted at least 12 weeks improved glucose control.

Aerobic exercise worked best, but resistance exercise (such as using weights) also worked well. More important than the type of exercise was the amount. Those people who exercised for at least two and a half hours a week (just over 20 minutes a day) showed the most impressive results.

The researchers said that the improvement in glucose control was about what you might see if you added a second glucose-control drug to someone’s medication.