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Chapter 3 Daily Lifestyle Activity

Individuals with all types of diabetes frequently are deconditioned and live a sedentary lifestyle. Therefore, the first major step in assisting them to exercise more regularly is to focus on incorporating more activities of daily living and other less structured physical activity into their lifestyles (Levine 2005, Johannsen 2008). The U.S. Physical Activity Guidelines (2008) refer to such activities as “baseline activity,” defined as the light-intensity activities of daily life like standing, walking slowly, and lifting lightweight objects. Although individuals vary in how much baseline activity they do, those engaging only in baseline activity are considered to be inactive. For the purposes of this book, daily lifestyle activity includes any unstructured movement done during each day.

Significant health benefits, such as a reduction in coronary risk factors, can be obtained by incorporating frequent bouts of moderate-intensity activity on most, if not all, days of the week, even if this activity is not a traditional, planned (or structured) one (McBride 2008, Loimaala 2009). A single bout of low-intensity, as opposed to high-intensity, exercise has been shown to substantially reduce the prevalence of hyperglycemia throughout the subsequent 24 h postexercise period in individuals with type 2 diabetes (T2D), demonstrating that activities of daily living also can have a positive effect on blood glucose management (Manders 2010). Although lifestyle physical activity does not entirely take the place of a traditional structured exercise program, in most cases it can be highly effective in helping individuals increase their daily activity level and build a fitness base that will allow them to participate in other, more intense or structured physical activities and exercise programs (Garber 2011).

Case in Point: Finding Time for Daily Movement

DC, a 62-year-old woman who has had T2D for 15 years, wants to do more exercise, but cannot find the time or the motivation to do so. Her medications include a daily evening injection of 70 units of long-acting basal insulin (insulin glargine), as well as a daily antidepressant. DC does not test her blood glucose regularly because of the high cost associated with buying strips for her meter (although she does have one). She has never been regularly physically active, and she has been significantly overweight or obese all of her adult life. Although she knows she needs to exercise, she says she has no time or energy left at the end of the day to do any exercise.

Resting Measurements

Height: 63 inches

Weight: 252 lb

BMI: 44.6 (morbidly obese)

Heart rate: 95 beats per minute (bpm)

Blood pressure: 125/80 mmHg

Fasting Labs

Plasma glucose: 116 mg/dl

A1C: 6.7%

Total cholesterol: 210 mg/dl

Triglycerides: 85 mg/dl

High-density lipoprotein cholesterol: 44 mg/dl

Low-density lipoprotein cholesterol: 149 mg/dl

Questions to Consider

1. Are DC’s actual reasons for not being more physically active the same as her stated ones?

2. What would be the most effective way for DC to increase her physical activity level?

3. What precautions (if any) would you recommend that DC take?

4. What strategies will help motivate DC to be more regularly active?

(Continued)

HEALTH BENEFITS OF DAILY MOVEMENT (UNSTRUCTURED ACTIVITY)

The health benefits of daily movement are numerous. For example, in sedentary men and women (without diabetes) undertaking either 6 months of fitness training or isocaloric pedometer-measured walking, their BMI, waist circumference, waist-to-hip ratio, and resting heart rate were reduced in both groups, and fasting glucose, glucose tolerance, and total cholesterol were similarly improved (Bell 2010). Thus, although supervised fitness training in previously sedentary adults produces greater improvements in their peak oxygen consumption and other fitness variables, many health-related variables improve similarly from a pedometer-based walking program matched for total energy cost.

Daily movement apparently has a large impact on how well the body handles carbohydrate intake. In a recent study, healthy normally active adults cut their physical activity levels (as monitored with daily steps) from >10,000 a day to <5,000, which is considered a sedentary level (Mikus 2012), over a 3-day period. Despite the fact that they could still release extra insulin in response to a glucose load, their postprandial glucose spikes increased significantly and progressively over the 3 days, which reinforces the importance of daily physical activity as a mediator of glycemic control.

For anyone with diabetes, inclusion of more daily, unstructured physical activity is likely to bestow similar, if not greater, health and glycemic benefits. Nonexercise activity thermogenesis (i.e., energy expended for activities of daily living) can create a large daily caloric deficit to prevent excessive weight gain, which can facilitate body weight and blood glucose management (Levine 2005, 2008). Simply standing counts as unstructured activity: in an observational study, obese individuals sat for ~2.5 h more and walked an average of 3.5 miles less per day than their lean counterparts. Moreover, most of the greater activity done by lean participants resulted from walks of short duration (<15 min) and low velocity (~1 mile/h) (Levine 2005). Health benefits result from concurrently reducing total time engaged in sedentary pursuits and interspersing frequent, short bouts of standing and physical activity between periods of sedentary activity, even in adults who are already physically active (Garber 2011, Dunstan 2012). Thus, how long individuals spend sitting each day and whether they move at all during periods of prolonged inactivity is critical to metabolic health and diabetes management.

PROMOTING LIFESTYLE PHYSICAL ACTIVITY

Engaging in frequent and daily physical activity is an essential part of self-care for all individuals with T2D. For anyone with type 1 diabetes (T1D), however, appropriate medication and dietary regimen changes likely will be needed to maintain control over blood glucose levels. All insulin users (regardless of type of diabetes) need to follow hypoglycemia prevention strategies. In many cases, the success of a physical activity should not simply be gauged by how much blood glucose levels decrease during participation. For insulin users, large drops in blood glucose are more likely to lead to rapid-onset hypoglycemia and worsened control. The focus instead should be on keeping the blood glucose level from interfering with the ability to continue the physical activity.

Although physical activity of any type—including activities of daily living—is not guaranteed to improve acute blood glucose control in insulin users, it is still equally important for them. For instance, one study recently investigated the influence of computer use on glycemic control in 115 patients with T1D. Their A1C levels were not related to age, diabetes duration, television watching, or computer use, but rather were independently and negatively associated with the weekly hours that individuals spent doing any physical exercise (Benevento 2010). Table 3.1 gives some suggestions on how to get individuals started doing more daily physical movement.

Table 3.1 Recommendations for Getting Started with More Daily Movement

Following are some suggestions on how to get individuals with any type of diabetes more physically active on a daily basis:

• Have them begin by focusing on more daily activities that are normal activities of daily living and involve physical movement of any sort, such as taking additional steps or standing longer each day.

• Once individuals have established a solid base of greater daily movement, encourage participation in other physical activities like brisk walking, but make sure that they start at a low level and progress slowly to enhance compliance and reduce injury risk.

• Have them include a variety of fitness activities to enhance differing aspects of their health. For example, yoga can reduce stress while improving overall health, well-being, and flexibility; aerobic activities like walking can help boost fitness levels; resistance and core exercises can lead to greater muscle strength; and ballroom or other dancing can improve balance, fitness, sense of enjoyment, and quality of life.

• Help individuals find ways to decrease the total time that they spend doing sedentary activities, even simply by standing up while talking on the phone or by taking frequent breaks from sitting.

• Encouraging individuals to move more and sit less will likely lead to their eventually incorporating activity with all types of goals.

Breaking Up Sedentary Time

Use of physical activity accelerometers has brought a better estimation of total daily movement, along with the time spent doing activities of varying intensities or nothing at all (like sitting or sleeping). In overweight and obese adults, interrupting sitting time with 2-min bouts of light- or moderate-intensity walking lowered their postprandial glucose and insulin levels (Dunstan 2012). Along the same lines, an individual would theoretically expend an additional 24, 59, or 132 kilocalories per day, on average, if he or she chose to stand up and walk around at a normal, self-selected pace for 1, 2, or 5 min every hour, respectively, compared with sitting continuously during an 8 h period (Swartz 2011). Making small changes like taking a 5-min walking break every hour could yield beneficial weight-control or weight-loss results.

In adults with newly diagnosed T2D (ages 30–80 years), each hour of sedentary time during waking hours was associated with a larger waist circumference and lower levels of HDL-C, suggesting that a higher sedentary time is associated with a worse metabolic profile (Cooper 2012). Using similar techniques with accelerometer measurements, others have confirmed that the proportion of time spent in sedentary pursuits on a daily basis is strongly related to metabolic risk, independent of how much physical activity an individual otherwise does (Bankoski 2011). Thus, people with diabetes in particular may benefit from reducing their total sedentary time and avoiding prolonged periods of sedentary behavior, which they can do simply by increasing the number of breaks from sitting that they take during the day.

Case in Point: Continued

A health-care or fitness professional working with DC needs to discuss her personal beliefs, past experiences, preferences, and concerns about increasing her activity levels to figure out how to best assist her in becoming more active on a daily basis. Upon further discussion with DC, it becomes clear that her actual reasons for not exercising differed slightly from what she stated. She agrees that she lacks the motivation to exercise and that she feels too tired after work to do it then. She is also afraid of getting low blood glucose, however, because she takes insulin daily. Moreover, she does not feel safe walking in her neighborhood, especially in the dark during the winter, and she cannot afford to join a fitness center or buy expensive equipment to use at home.

(Continued)

KEEPING TRACK OF DAILY MOVEMENT

One way individuals can keep track of how much daily movement they are doing is through the use of pedometers, which are small monitors that record the number of steps taken during the day. They have proven to be useful tools for increasing lifestyle physical activity because they provide immediate feedback, build confidence (in being active), and enhance enjoyment of daily movement. Use of objective measures of daily activity like step counters may enhance reaching goals. A meta-analysis of 26 studies with a total of 2,767 participants (eight random-controlled trials and 18 observational studies) found that pedometer users increased their physical activity by 26.9% over baseline during an average intervention of 18 weeks (Bravata 2007). What best predicted increased levels of physical activity was the establishment of a goal like taking 10,000 steps a day. Tips for the effective use of pedometers are given in Table 3.2.

Table 3.2 Effective Use of Pedometers (Step Counters)

Following are some points to consider when advising diabetic individuals on how to most effectively use pedometers to promote and record daily physical activity:

• Pedometers are capable of recording ambulatory activity, such as walking, jogging, or running. They will not count steps during cycling, rowing, upper body exercise, swimming, and other activities. However, steps can be estimated using metabolic equivalent (MET) levels for activities (see some equivalent values in Table 3.3).

• For most adults, 2,000 steps is the equivalent of about 1 mile of walking, but the recorded steps can be affected by stride length, pedometer accuracy, and other factors.

• The most essential feature of any pedometer is the step count. Pedometers are most accurate in counting steps, less accurate in calculating distance walked, and even less accurate at estimating caloric expenditure.

• A variety of factors can affect step=counting accuracy, such as walking speed, waistband type, and abdominal size. In general, most pedometers are fairly accurate step counters at speeds of 2.5 mph and above.

• Pedometers are more accurate at counting steps when attached to a firm waistband in an upright position and placed to the side (directly up from the knee cap on either side); attachment of pedometer to loose waistbands typically leads to an underestimation of steps taken.

• Having a large waist size can negatively impact step-counting accuracy. For anyone with a large abdomen (or for pregnant women with any type of diabetes), place the pedometer at the small of the back, or use one that can be placed in a pocket or other location (like around the knee).

• Go for simplicity, but accuracy, in a pedometer: extensive bells and whistles are not required. Recommended brands include most Accusplit, Yamax, and Omron models.

• To test a pedometer’s accuracy, an individual should position the device on his or her belt or waistband in line with one knee on either side of the body and reset the pedometer’s count to zero. When taking 20 steps at a typical walking pace, if the pedometer records between 18 and 22 steps, it is reasonably accurate. If not, reposition it and try again. If it repeatedly fails this test, look into buying another type.

• A “physically active” adult is expected to accumulate at least 10,000 steps per day (or the step equivalent if engaging in activities that a pedometer cannot easily record).

• Establish a baseline by tracking steps for a few days without intentionally increasing physical activity level.

• Set appropriate step goals by progressively increasing steps from baseline using small increases to start, such as taking an extra 500−1,000 daily steps.

Although pedometers are most suitable for tracking walking-based activities, they cannot detect changes in type, intensity, or pattern of activity. Some step equivalents for various activities are alternately given in Table 3.3 (based on metabolic equivalents, or MET levels) (Ainsworth 2011). Accelerometers and global positioning system (GPS) devices alternately may be used to detect such movements and are gaining popularity for use in determining total daily movement (Webber 2009).

Table 3.3 Step Equivalents for Various Physical Activities

Case in Point: Wrap-Up

To overcome DC’s barriers to and any possible concerns associated with being physically active, a professional makes the following suggestions to her:

1. Start with more daily movement. The best way to start is by simply doing more daily movement and by being as active as you can all day long. Every step you take during the day counts. If you are just starting out, start with 10 min a day and add extra minutes a little bit at a time. Work up to 10 min at a time, three times a day, during the day—on breaks, during lunch, or whenever you can fit it in.

2. Do not wait until you are tired to exercise. Another trick is to try to fit in more steps and movement at the time of day when you have more energy. Just try walking for as long as possible during your lunch break a few days each week. You’ll find that the more you do, the more energy you actually will have.

3. Stand up more. Also, instead of sitting down, try standing up for an extra 10 min a day—while you are talking on the phone, stuck in a meeting (stand next to the wall), or just waiting somewhere. Standing is a physical activity that most of us could afford to do more of, so start thinking about ways to stand more every day. It also helps break up your sitting time, which helps use up blood glucose and keep you healthier.

4. Be active in your home. Even at home, make physical activity part of your daily routine. For example, exercise while you watch television (even if it just consists of walking in place), do some cleaning around the house, or do something active with your family and friends.

5. Learn how to adjust your insulin dose, and be prepared to treat a low. Because you use insulin, ask your doctor or health-care provider about how much you might need to lower your insulin dose as you start to be more regularly active. Any physical activity can make insulin work better, so just make sure that you are prepared to treat a low blood glucose level if you have one. Keep some easily absorbed carbohydrates with you during your activity, such as glucose tablets, hard candy, sports drink, or even crackers.

6. Focus on activities that you can safely do indoors. Because you cannot walk outside in your neighborhood (at least part of the time), try to find an inexpensive indoor activity that you can do, such as an exercise class at a community center. Also, think of activities you can do in the safety of your home, including all types of home-based exercise programs and videos. Some programs are also shown on television channels at various times of day. You do not need expensive equipment to work out in your home either. Try walking in place, doing stretching, or using food cans or water bottles for weights. You may want to buy some inexpensive resistance bands to use at home.

7. Get support from friends and family by involving them. Finally, if you are still lacking the motivation to exercise, invite a family member or friend to exercise with you on a regular basis (like having a friend walk with you during lunch). Plan when you are going to do each type of activity.

Doing more daily movement is not as effective as most structured exercise programs in increasing fitness levels, but it is important for many other reasons, including expending extra calories, breaking up sitting time, and building a fitness base in individuals who are overweight or sedentary. Use of pedometers may motivate individuals to engage in more unstructured physical activities. In addition, once individuals have successfully implemented more physical activity into their daily lifestyle, they likely will feel more confident, ready, and able to initiate and keep participating in more structured forms of activity.

Professional Practice Pearls

• All adults should avoid inactivity. Some physical activity is better than none, and participation in any amount of physical activity bestows health and glycemic benefits.

• The best way for deconditioned or overweight individuals with diabetes to start being more physically active is to focus on increasing their daily movement first.

• Daily movement (or unstructured physical activity) includes taking more daily steps, standing more, and doing more activities of daily living like housework.

• Individuals with diabetes will benefit from simply reducing their total sedentary time and avoiding prolonged periods of being sedentary by taking frequent breaks.

• Pedometers are step counters that can be used to track unstructured physical movement throughout the day; go for simplicity, but accuracy, in a pedometer.

• Walking-based activities are the best use for pedometers as they cannot detect changes in type, intensity, or pattern of activity; however, accelerometers and GPS devices can.

• For most adults, 2,000 steps is the equivalent of ~1 mile of walking, but step equivalents of other activities (like swimming) can be estimated based on MET levels.

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