Before Getting Started: Safety Considerations

If you are planning a program of regular physical activity, you have many options to choose from, including aerobic (endurance) training, such as biking, walking, running, and swimming, resistance training (weight lifting, floor exercises), and flexibility (range of motion) training (yoga and stretching). The best program of physical activity will combine these different basic types of exercise into a whole-body training program. However, whatever physical activity you choose, it must be appropriate for your physical abilities.

Pre-exercise exam

Your healthcare provider will determine whether it is necessary to do a pre-exercise examination, depending on the intensity of the physical activity your are planning to engage in and other factors, such as your age and existing health problems. For most people, with type 2 diabetes who want to engage in low-intensity physical activity, such as walking, no pre-exercise examination is necessary. However, if you are an older person not used to physical activity, you will benefit from an assessment.1

Since physical activity is such an important part of your diabetes care plan, work with your healthcare provider or certified diabetes educator (or a trainer experienced in working with people with type 2 diabetes) to plan program regular of physical activity will fit in with other parts of your care plan, including your medication and eating plan. Another important consideration that will affect the way you approach physical activity is whether you have common diabetes complications, including vision problems (retinopathy), cardiovascular disease (including heart disease), kidney disease, or nerve complications (neuropathy). None of these problems should keep your from getting regular physical activity, but you will need to take precautions so that the extra physical demands of physical activity don’t lead to any serious health problems.

Before beginning your training program, there are a number of issues you should discuss with your healthcare provider. These include topics such as2:

        • Intensity of physical activity (heart rate), duration (length), and frequency
        • T– Timing (during the day) for physical activity, especially in relation to medication use and eating
        • High risk activities that should be avoided

Questions to ask your healthcare provider before
starting your exercise plan22

How hard should I work?
  • Find out what intensity level is appropriate for you
  • Ask whether you should monitor exercise intensity using a heart rate monitor
  • Find out what your target heart rate should be and how long you should keep your heart rate above a certain level
What should I avoid doing?
  • Your healthcare should be able to give you a list of exercises to avoid
  • For instance, if you have problems with the nerves in your feet, you may want to avoid running
When during the day should I exercise?
  • When you put together your exercise plan, you’ll be coordinating exercise with other parts of your diabetes care plan
  • This means that certain times of day will be better for exercise than others, in terms of when you eat and when you take your diabetes medications
How will exercise affect my medication or insulin?
  • Your healthcare provider will help you develop a plan for monitoring your blood glucose and determining whether you will need to adjust your medication or insulin dosing to take into account the effects of exercise on blood glucose
Are there danger signs I should be aware of?
  • Depending on your general health, your healthcare provider may want you to watch for signs that you are putting too much stress on your body or that your blood glucose is becoming too low (hypoglycemia)
  • Signs of heart problems that you should be aware of include chest pain, shortness of breath, and dizziness
What precautions should I take when I exercise?
  • Work with your healthcare provider to develop an action plan for when you exercise that will allow you to head off problems
  • For instance, you may want to carry a snack or glucose pills for times when your blood glucose gets low
  • You should also make sure that your exercise equipment is safe, that your shoes fit and don’t cause blisters
  • Always make sure that you are properly hydrated

Consider working with a specialist

Your healthcare provider may want you to work with someone who specializes in helping people with chronic diseases like diabetes develop a safe and effective program of physical activity. This is especially true if you are over the age of 35 and have cardiovascular disease or are at high risk for heart disease or stroke or if you have diabetes complications, including nerve problems or kidney disease. Even if you are generally fit and just want to engage in moderate- or high-intensity exercise (like training for a marathon), your healthcare provider may want to exercise caution and have you evaluated by a specialist.

If you work with an exercise physiologist, he or she may have you do specialized tests measuring your endurance, body fat, strength, and flexibility to get a more accurate picture of your fitness level. This specialist may have you do an exercise stress test to determine how physical activity will affect your cardiovascular system. During this test, your heart and blood pressure are monitored while you exercise at different intensity levels (typically during an exercise stress test you are asked to walk on a treadmill).

Determining your target heart rate

Determining your target heart rate is a good way to make sure that you are exercising hard enough, but not overdoing it. You can use this simple target heart rate calculator to find out how hard you should be working during physical activity2.

Resting heart rate. The first step is to determine your resting heart rate. You should do this measurement before you get up and going in the morning, so that it is truly a measure of your resting heart rate. Before you get up out of bed in the morning, count the number of beats your heart makes during 1 minute.

Maximum heart rate. Your maximum heart rate is determined based on your age. To find this out, simply subtract your age from 220. This gives you your maximum heart rate reserve.

For instance, if you are 50 years of age, then 220 – 50 gives you a maximum heart rate of 170 beats per minute. If your resting heart rate was 70 beats per minute, then your maximum heart rate reserve is 100 beats per minute.

Multiplying your maximum heart rate reserve by .70 gives you 70% (70 beats per minute) of your heart rate reserve and by .50 gives you 50% (50 beats per minute) of your heart rate reserve.

The one final step is to add your resting heart rate (70 beats per minute) to both 50% and 70% of your maximum heart rate reserve. This gives you the range 120 to 140 heart beats per minute, the heart rate target range that you should stay within during physical activity.

Figuring out your target heart rate (HR)

Subtract your age from 220 for your maximum HR 220 – YOUR AGE (example: 50) = 170
Subtract your resting HR from your max HR 170 – RESTING HR (example: 70) = 100
Multiply the answer by 0.7 and 0.5 0.7 X 100 = 70 (70% of max reserve HR)
0.5 X 100 = 50 (50% of max reserve HR)
Add your resting HR to each of these numbers to get your target HR range 70 + 70 = 140 beats per minute
50 + 70 = 120 beats per minute
While you are exercising your heart rate should stay between 120 and 140 beats per minute

Precautions you should take if you have diabetes complications

Medical complications, including cardiovascular complications (heart disease, high blood pressure), neuropathy (nervous system disorders), retinopathy (eye disease), and kidney disease (nephropathy) are common in people with diabetes. You may have one or more of these complications. However, this shouldn’t keep you from getting regular physical activity. However, you will need to take some special precautions in order to stay safe while you are active.

Learn more about diabetes-associated complications.

Nervous system complications. There are two main types of nerve disorders that may affect your ability to engage in certain physical activities. These include peripheral neuropathy, in which nerves in the extremities (your legs and feet) are damaged and don’t function normally, and autonomic neuropathy, in which the nerves that control automatic functions of the body, such as the beating of our heart or breathing, are damaged and do not function normally.

One type of peripheral neuropathy that is particularly common in diabetes is nerve damage affecting the feet. If you have this type of neuropathy, your feet may be numb and you may not have normal sensation. If this is the case, when you select a form of physical activity, you may want to avoid weight-bearing and impact activities, such as jogging or even walking (especially over rough terrain). Instead, you may want to try swimming or using a stationary exercise bicycle or another type of exercise machine used in aerobic training, without impacting your feet. Whatever activity you choose, if you have numbness that affects your feet, you should make sure that you have well-fitting and comfortable shoes to prevent blistering.3

With autonomic neuropathy affecting the heart and blood vessels, you will need to be careful with aerobic (endurance) training that raises your heart rate and blood pressure. Talk to your doctor and an exercise physiologist about what forms of training you can do and whether you will require special equipment to monitor your heart rate and blood pressure during training.

Eye disease. . If you have eye or vision complications associated with diabetes, in particular a disorder called proliferative retinopathy, you will want to avoid particularly strenuous physical activity that results in rapid increases in blood pressure. Vigorous physical activity, such as weight lifting and intensive aerobic activities (such as long-distance running or sprinting) that increase your blood pressure may cause bleeding in your eye if you have retinopathy. Instead of intensive forms of physical activity, choose walking, jogging, or bicycling. Talk to your healthcare provider and/or optometrist or ophthalmologist about what forms of training they recommend and what special precautions you should take to protect your vision during training.3

Cardiovascular disease.. People with diabetes are at increased risk for cardiovascular disease, including heart disease and high blood pressure. If you have heart disease or high blood pressure, talk to your healthcare provider about what precautions you should take during training. In general, you will want to avoid training too vigorously and putting too much strain on your heart and circulatory system. Instead of highly intense endurance training, such as long-distance running, or weight lifting, which can result in rapid increases in blood pressure, you should try more gentle forms of physical activity, such as walking, bicycling, light jogging, or swimming2.

Kidney disease. If you have chronic kidney disease, you can take part in aerobic activity and resistance training (also called strength training), as long as you make sure to start with a low-intensity workout and only increase intensity gradually, without putting too much demand on your body. Low-intensity aerobic training, such as walking or bicycling, are good options.3

Blood glucose and exercise

Physical activity puts an extra demand on the body to burn glucose for energy. If you have type 2 diabetes and take certain diabetes medications that increase risk for hypoglycemia, you should be aware of the risk for developing hypoglycemia during physical activity. Risk for low blood sugar (hypoglycemia) is increased in people who are being treated with insulin or diabetes medications that cause insulin secretion (called secretagogues), including sulfonylureas and glinides (repaglinide and nateglinide).1,4

Written by: Jonathan Simmons | Last reviewed: May 2014.
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