Cardiovascular disease (CVD) is one of the leading causes of death in industrialized countries such as the United States. Cardiovascular disease includes medical conditions and diseases such as heart attacks, chronic chest pain, stroke, and heart failure. While the number of deaths attributable to CVD has declined over the last decade in the United States, the overall public health burden of CVD remains unacceptably high, and both men and women are affected. According to the American Heart Association (AHA), the overall death rate linked to CVD in 2011 was 229.6 deaths per 100,000 Americans, or a total of 786,641 deaths (15). Stated another way, more than 2,150 Americans die of CVD every day, which means that 1 death occurs every 40 seconds. Moreover, this is not a disease that affects only older adults—approximately 155,000 of the deaths were in adults younger than 65 years of age. The costs associated with CVD are astronomically high. In 2011, the annual costs for CVD and stroke were estimated at approximately $320 billion (15).
What causes CVD? Cardiovascular disease often starts with damage to the cells lining the inside of blood vessels, and inflammation plays a key role in CVD progression (13). The disease process is known as atherosclerosis. As one example, blood vessels in the heart that are partially or fully blocked with plaque can impair blood flow. In some cases, a partially blocked vessel causes chest pain with exertion; this is known as angina. In other cases, the plaque that blocks the blood vessel can rupture, cause a blood clot inside the blood vessel, and therefore cut off the blood supply (14). If the blood flow is not immediately restored, the heart muscle will be damaged; this is referred to as a myocardial infarction or, simply, heart attack. A heart attack can weaken the heart muscle, sometimes leading to heart failure, which is associated with symptoms such as shortness of breath, fatigue, and fluid retention.
Fortunately, CVD is largely preventable. Lifestyle management through proper diet and regular physical activity underlies CVD prevention and treatment (11).
Risk Factors for Cardiovascular Disease
It is important to emphasize that CVD prevention includes preventing the development of risk factors, treatment of risk factors, and prevention of recurrent CVD events. Risk factors for CVD include several that cannot be altered such as increasing age, having a family history of CVD, race, and sex (men are at greater risk then women). More importantly, there are many risk factors that can be altered through lifestyle modifications; these include cigarette smoking, high blood pressure, high cholesterol, physical inactivity, obesity, and diabetes (7). These risk factors are highlighted in table 12.1 and discussed in the following sections. In addition, other factors such as excessive alcohol consumption and stress can contribute to the development of CVD. Consistent with the overall theme of this book, this chapter focuses on proper diet and physical activity in relation to CVD. In particular, lifestyle choices that lead to optimal cardiovascular health and improved quality of life are emphasized.
As you can see, many risk factors for CVD can be altered with lifestyle changes. Focusing on modifiable aspects is a positive step you can take to promote heart health.
Cigarette Smoking
While tobacco use has declined in the United States, there are still far too many people who smoke. In 2013, approximately 18 percent of adults and 16 percent of high school students smoked. The AHA estimates that nearly one-third of heart disease deaths are attributable to smoking and exposure to secondhand smoke (15). Of recent concern is the use of e-cigarettes and the possibility that they may serve as a gateway to traditional cigarettes. If you are a smoker, quitting immediately is one of the most important things you can do to improve your overall health. Many smokers require assistance before quitting—consult your health care provider for additional information.
High Blood Pressure
Known as the “silent killer,” high blood pressure (or hypertension) is a major contributing factor to the development of CVD (19). The word “silent” highlights that there are often no outward signs or symptoms of high blood pressure. Blood pressure recordings include the systolic blood pressure (top number) and diastolic blood pressure (bottom number), and the unit used is millimeters of mercury (mmHg). An optimal blood pressure is a systolic blood pressure less than 120 mmHg and diastolic blood pressure less than 80 mmHg. Systolic pressures between 120 and 139 or diastolic pressures between 80 and 89 are classified as prehypertensive blood pressures, and generally signal that an individual is at greater risk for higher blood pressures in the future. However, when the systolic pressure exceeds 140 mmHg or the diastolic pressure exceeds 90 mmHg, a diagnosis of hypertension is usually made by a health care provider (10). It is important to note that values must be confirmed on at least two separate occasions before a diagnosis is made.
Among all U.S. adults, nearly one-third have hypertension, which represents approximately 80 million people (15). Hypertension rates are especially high in African Americans. Blood pressure values usually increase with age. There are many treatment options for hypertension, and lifestyle modifications such as proper diet and exercise, as discussed in this chapter, are key to achieving optimal blood pressure values (18).
High Cholesterol
Elevated levels of cholesterol in the blood contribute to the development of CVD. Values above 200 milligrams per deciliter (mg/dL) increase risk for CVD. Unfortunately, nearly 31 million U.S. adults have cholesterol values above 240 mg/dL (15). In addition to the importance of assessing the total amount of cholesterol in the blood, it is common to check for levels of low-density lipoprotein (LDL) cholesterol, which is often referred to as “bad” cholesterol, and high-density lipoprotein (HDL) cholesterol, which is often referred to as “good” cholesterol. Low-density lipoprotein values below 100 mg/dL and HDL values above 60 mg/dL are desirable. Individuals with CVD should strive for even lower LDL values to decrease their risk of having a cardiovascular event (21). While proper nutrition and regular exercise are important lifestyle modifications to help reach optimal cholesterol levels, many adults with CVD also require medication to get their LDL levels down to an acceptable range. If your cholesterol is too high, you should work with your health care provider to take steps to lower your levels to recommended ranges in to order decrease your risk of having a cardiovascular event. The most common class of medications used is known as statins. In rare situations, statin use can lead to rhabdomyolysis (skeletal muscle protein is abnormally released into the blood, with subsequent damage to the kidneys). When someone taking a statin performs exercise, muscle discomfort or pain could be a result of the medication rather than the exercise. People in this situation should report any uncommon muscle discomfort or pain to their health care provider.
Physical Inactivity
Having a sedentary lifestyle is major risk factor for CVD. Nearly 31 percent of adults in the United States do not engage in any leisure-time physical activity (15). This is a major public health issue. Having a high level of habitual physical activity has its own independent health benefits, but high activity levels also favorably influence several other risk factors such as obesity, prediabetes, high cholesterol, and high blood pressure. Exercising regularly also helps to maintain mobility in old age and to prevent frailty. Quality of life measures are higher in adults who exercise regularly. The standard recommendation is for adults to get at least 150 minutes of moderate-intensity aerobic activity per week, which can be accomplished with brisk walking, or 75 minutes of vigorous-intensity exercise per week (25). Additional details regarding exercise recommendations are provided later in this chapter.
Obesity
Excess body weight is a leading cause of death and disability in the United States. Being overweight or obese makes it more likely that you will have other cardiovascular risk factors. In particular, people who are overweight or obese are far more likely than others to have type 2 diabetes. Sixty-nine percent of adults in the United States are classified as overweight or obese, and these high rates are viewed as a public health crisis. Unfortunately, far too many children are classified as overweight or obese; approximately 32 percent of children between 2 and 19 years of age fall into this category. Sadly, obese children usually become obese adults (15).
Prediabetes and Diabetes
Fasting blood glucose (i.e., sugar) should be less than 100 mg/dL for children and adults. Values higher than this suggest prediabetes or diabetes. The latest statistics suggest that 21 million adults have diagnosed diabetes, 8 million have undiagnosed diabetes, and 81 million have prediabetes (15). Those with prediabetes have fasting blood glucose values between 100 and 125 mg/dL; those with diabetes have fasting blood glucose values greater than or equal to 126 mg/dL (2). Having diabetes dramatically increases your chances of developing CVD. Fortunately, regular exercise and proper nutrition can help prevent the development of diabetes.
Diet
A healthy diet provides many potential benefits for health and for risk factor reduction. The relationships between nutrition choices and cholesterol levels, blood pressure, and heart disease highlight the value of heart-healthy eating (as discussed in greater detail in the next section).
Healthy Approaches to Managing CVD
Diet and physical activity are two important lifestyle factors that promote cardiovascular health (11). These are two lifestyle factors over which you have control. Nutrition and exercise can contribute to optimizing the health of your heart and blood vessels, as well as your overall fitness.
Focusing on Nutrition
Nutrition plays an important role in cardiovascular health. Poor nutrition is considered a risk factor for elevated cholesterol levels, high blood pressure, and heart disease. Unfortunately, the average American diet increases risk for all of these conditions. The typical American diet is high in refined grains, added sugars, and red and processed meats while falling short in key food groups such as vegetables, fruits, whole grains, and dairy (22). In particular, you should thoughtfully review the composition of your diet and consider changing the types of fats you eat and lowering your sodium intake and the calories you consume while increasing whole grains, lean proteins, fruits, and vegetables to promote optimal heart health. Indeed, research has shown that a healthy dietary pattern is beneficial for reducing CVD risk (22).
Heart-Healthy Dietary Recommendations
Consuming a heart-healthy diet is not as difficult as it sounds if you carefully consider the types of foods you should include. For instance, selecting whole grains over refined grains is a great first step. Whole grains are found in many foods, including cereals, grains, pasta, and brown rice (e.g., look for the word “whole” in front of the type of grain). Aim for at least three servings of whole grains a day. Further, whole grains provide fiber, which includes two types: soluble and insoluble. Soluble fiber can help to lower LDL-cholesterol levels. Good sources of soluble fiber include oatmeal, fruits, vegetables, and kidney beans. Total fiber intake should be in the range of 20 to 30 grams, with 10 to 25 of those grams coming from soluble fiber sources (12). When it comes to fruits and vegetables, aim for five servings a day. Select a variety of colorful fruits and vegetables to increase your intake of nutrients. Sources can include fresh, frozen, or dried fruit and fresh, frozen, or canned vegetables without added fat or salt. Remember, sodium is often added to canned vegetables. For protein, select lean protein sources, options include both animal and plant based foods. Lean cuts of beef and pork (loin, leg, round, extra-lean ground beef), skinless poultry, fish, and venison are good animal-based choices, while dried beans and peas, nuts and nut butters, egg whites, or egg substitutes constitute great plant-based sources of protein. Adequate protein is important in the diet, although too much can be detrimental as it provides excess calories that are stored as fat.
Q&A
Are fruit juices an ideal source to meet serving recommendations for fruit consumption?
While fruit juices do come from fruit, they also provide a lot of calories and contain no fiber, so it is best to get fruit from whole sources.
Fat and Cholesterol Recommendations
While most people have heard the recommendation to eat a low-fat, low-cholesterol diet, or a heart-healthy diet, you may not know that the source of fat in your diet is the most important consideration as opposed to overall content. Health agencies such as the Academy of Nutrition and Dietetics (AND) and the AHA recommend keeping dietary fat between 25 and 35 percent of your daily caloric intake. While this may not seem low enough to you, the type of fat you consume is very important to heart health. Several types of dietary fat exist, as discussed in chapter 3. Saturated fats contribute to the blocking of your arteries by increasing LDL-cholesterol levels. Several large research studies have revealed that for every 1 percent increase in calories from saturated fatty acids as a percent of the total calories consumed, LDL-cholesterol levels rise about 2 percent in individuals who have high blood cholesterol levels (12). For every 1 percent reduction in saturated fatty acid intake, serum cholesterol is reduced by approximately 2 percent. Therefore, AHA and the American College of Cardiology both recommend that less than 7 percent of your daily calories come from saturated fats (11). Saturated fat is predominantly found in animal sources such as meat and dairy products including fatty beef, lamb, pork, poultry with skin, beef fat, lard, and cream, butter, and cheese (5). Another type of fat called trans fat should be consumed as little as possible because it tends to increase LDL-cholesterol similarly to saturated fatty acids (11), as well as decrease HDL cholesterol (6). If you see the words “hydrogenated” or “partially hydrogenated” on the ingredient list for a food, that food item contains trans fats. Examples of foods containing trans fat include stick margarine, shortening, some fried foods, doughnuts, cookies, crackers, muffins, pies, and cakes. You should limit your intake of these types of products. Finally, your cholesterol intake is still important to consider. Cholesterol not only comes from the foods you eat but can also be produced by the body. Limiting your body’s production of cholesterol and reducing blood cholesterol levels are best achieved by reducing your cholesterol and dietary saturated fat intake. Cholesterol is found in foods such as meat (particularly those with lots of visible fat); processed meats such as sausage, bologna, salami, and hot dogs; egg yolks; whole milk; cheeses; shrimp; lobster; and crab. You can easily lower the cholesterol content of your diet by choosing lean cuts of meat with minimal visible fat and leaner cuts of beef such as round, chuck, sirloin, or loin.
So, if saturated and trans fats as well as cholesterol are the types of fat you should limit, what should you consume? Unsaturated fats are recommended to make up most of the fat you consume (as covered in chapter 3). These fats are known as monounsaturated and polyunsaturated fats. Monounsaturated fats can be found in oils such as canola, peanut, and olive oil. Polyunsaturated fats are generally found in vegetable oils but also include the omega-3 fats. Omega-3 fats are found in several types of fish including salmon, tuna, mackerel, herring, lake trout, albacore tuna, and sardines but can also be found in oils including canola and soybean. Omega-3 fats are thought to decrease your risk of heart disease; adding two servings of baked or grilled fish (about 3.5 ounces or about 100 grams) to your diet each week is one way to increase your intake of healthy fats such as the omega-3 fats and is recommended by the AHA (4). If you are unable to get your omega-3s from fish, your health care provider may recommend fish oil supplements. The AHA recommends that people with heart disease get 1 gram of omega-3 fatty acids from a combination of EPA and DHA (two types of omega-3 fats) daily (9).
Dietary Sodium Recommendations
While lowering your intake of foods such as saturated fat that increase cholesterol levels in the body is important, lowering sodium intake is equally so. Most Americans consume far too much sodium. The U.S. Department of Agriculture estimates that the current average intake for both men and women is ~3,300 milligrams of sodium (23). Many organizations recommend sodium reduction, including AHA, AND, and the World Health Organization. The Dietary Guidelines for Americans recommends 2,300 milligrams of sodium or less per day; and for those with established hypertension, a lower target of 1,500 milligrams per day is the aim (22). These recommendations are based on research studies that have documented a decline in blood pressure with dietary sodium restriction (9, 20). More recently there has been a push to recommend the 1,500 milligrams per day level for most Americans. So, where does all this sodium come from? Well, 75 percent of typical sodium intake comes from processed, prepackaged, and restaurant foods. Most food items found in a box or a can contain sodium (even breakfast cereals!). Therefore, looking closely at food labels and comparing products to find one with less sodium is recommended.
Q&A
What are some ways to reduce sodium consumption?
If you add table salt to your food, a great place to start is to get rid of the salt shaker, though this will not be enough. Shopping wisely and reading labels are very important. Looking for labeling on packages that say “very low sodium,” “low sodium,” “lite in sodium,” “reduced sodium,” “sodium-free,” or “salt-free” is a great way to reduce sodium consumption.
Other Recommendations
Weight control is also important for decreasing your risk for CVD or even for managing your heart disease or blood pressure (8). Anyone who is overweight or obese (to check your body mass index [BMI], see figure 18.1) should focus on reducing total calorie intake and burning more calories through exercise. Studies have reported that weight loss can lower blood pressure, as well as improve overall cardiovascular health (for more details on weight management, see chapter 18). A critical review of your own diet and the decision to consume fruits, vegetables, and whole grains in preference to high-fat, highly processed options are very conducive to weight loss.
Finally, there has been speculation about the benefits of alcohol in relation to heart health. The AHA recommends moderation when it comes to alcohol consumption. This corresponds to one to two drinks per day for men and one drink per day for women (8). Drinking too much alcohol can increase some fats in the blood (i.e., triglycerides). In addition, alcohol intake can influence blood pressure. For those who consume alcohol on a regular basis, reducing alcohol intake has been shown to lower resting blood pressure.
Q&A
What about red wine and heart disease?
Some researchers have suggested that red wine may be associated with the reduced mortality seen with heart disease in some populations. Unfortunately, it is not clear if it is truly the wine or the grapes themselves or other components in red wine that may contribute to the reduced mortality. Further, it is difficult to separate out other lifestyle factors that may play a role. There has been evidence to suggest that drinking wine or alcohol in some populations can increase HDL cholesterol. However, regular exercise can do the same and has many more benefits.
Heart-Healthy Diet Plans
There are many heart-healthy diets that are recommended for people who have heart disease or high blood pressure. One diet called Therapeutic Lifestyle Change, or TLC, may be recommended to you by your health care provider if you have high blood cholesterol or known CVD (16). This diet emphasizes reduced saturated fat and cholesterol intake with consumption of plant stanols/sterols and increased soluble fiber (see table 12.2). This diet was designed to lower LDL-cholesterol levels in the body. Consumption of plant stanols/sterols in the amount of 2 to 3 grams per day has been shown to lower LDL cholesterol by 6 to 15 percent (12). Further, fiber is important to consider, particularly soluble fiber. Research has shown that an increase in soluble fiber of 5 to 10 grams per day is associated with a 5 percent reduction in LDL cholesterol (26). Finally, total calorie (energy) intake should be adjusted to maintain a healthy body weight, and physical activity should be included to expend at least 200 kilocalories per day.
If you have elevated blood pressure, your health care provider may talk to you about the DASH diet or Dietary Approaches to Stop Hypertension diet (17). This diet evolved from several research studies conducted in the 1990s that showed the effect of this diet on blood pressure (9, 20). These dietary trials emphasized a low-sodium diet with consumption of foods rich in potassium, calcium, and magnesium. A 2,000-calorie DASH diet provides 4,700 milligrams of potassium, 1,240 milligrams of calcium, 500 milligrams of magnesium, 90 grams of protein, 30 grams of fiber, and 2,400 milligrams of sodium. Potassium, in particular, has been shown to have blood pressure–lowering properties (1). Food sources of potassium include milk, meat, fish, fruits (e.g., bananas, oranges, and other citrus fruit), and vegetables (e.g., potatoes, broccoli, carrots) (24).
Information on the DASH diet, including sample menus, can be found on the AHA website or the National Heart, Lung, and Blood Institute (of the National Institutes of Health) website (go to www.nhlbi.nih.gov and enter DASH into the search window). This site includes specific examples of healthful eating habits. In general, the recommendation is to eat several servings of fruit, several servings of vegetables, several servings of grains (with an emphasis on whole grains), and fat-free or low-fat milk products daily. You should limit fat, oils, and sweets and incorporate lean meats, poultry, and fish into your diet. The overall recommendation for hypertensive adults is to adopt the DASH eating plan; the number of servings for each of the food group categories depends on your overall caloric intake (see table 12.3 for some general guidelines for the number of servings from various food groups). DASH is organized by servings for most food groups. The following are examples of DASH servings:
· Grains—1 ounce or equivalent; 1 slice bread
· Fruits—1/2 cup cut-up fruit or equivalent; 1 medium fruit
· Vegetables—1/2 cup cooked vegetables or equivalent; 1 cup raw leafy vegetables
· Meats, poultry, and fish—1 ounce cooked meats, poultry, or fish or one egg
· Nuts, seeds, and legumes—2 tablespoons peanut butter, 1/3 cup or 1 1/2 ounces of nuts, 1/2 cup cooked beans, or 1 cup bean soup
· Fats and oils—1 teaspoon soft margarine or vegetable oil, 1 tablespoon mayonnaise, 1 tablespoon regular salad dressing or 2 tablespoons low-fat dressing
· Sugars—1 tablespoon jam or jelly, 1/2 cup regular gelatin, or 1 cup regular lemonade
There are a few additional considerations related to diet if you are on medication. For instance, individuals who are on warfarin (i.e., Coumadin) should keep their vitamin K intake consistent to maintain stable levels of the drug in their body. Vitamin K is found in green leafy vegetables such as kale, spinach, swiss chard, romaine lettuce, green leaf lettuce, mustard greens, and collards, as well as broccoli and asparagus. People taking diuretics may experience increased frequency of urination and as result may excrete more minerals, such as potassium, calcium, phosphorus, and magnesium, in their urine. Consult with your health care provider if you have any concerns before making any changes to your diet.
Focusing on Physical Activity
High levels of habitual physical activity and structured exercise improve functional capacity and can help forestall the inevitable age-related declines in physiological function. Habitual physical activity and exercise also favorably influence many of the risk factors for CVD. This section focuses on exercise considerations for individuals with CVD.
Precautions for Exercise
Many individuals with heart disease, or risk factors for heart disease, have concerns related to cardiovascular events, such as a heart attack, when engaging in physical activity. An increased risk is seen particularly when people who are sedentary or who have CVD do vigorous-intensity exercise. This risk decreases, however, with regular physical activity (2). Thus, starting with low to moderate exercise and progressing gradually is key to promote safety along with improvements in health and fitness.
Proper screening is important for anyone about to begin an exercise program. To promote safety, individuals with a history of CVD should have medical clearance before beginning an exercise program. The medical clearance should include a medical exam by a health care professional, and very often an exercise test is also performed (2). If you have CVD, you may have started your exercise program in a cardiac rehabilitation facility. The principles that were used to design your exercise program in the cardiac rehabilitation program are likely similar to the principles discussed in this chapter.
Physical Activity Recommendations
Physical activity recommendations are similar in many ways to what has been presented in earlier chapters, although some special considerations for those with CVD are discussed in this section. A complete exercise program includes aerobic exercise, resistance training, and flexibility and neuromotor exercises.
Aerobic exercise should be performed at least three, but preferably most, days of the week. Exercising more frequently than three days per week can be helpful for people who want to lose weight because more frequent exercise causes expenditure of more calories. For those with high cholesterol, ACSM recommends at least five days per week to help maximize caloric expenditure. Also, each exercise bout can lower blood pressure for several hours, so exercising more frequently (five to seven days per week) can help persons with hypertension (2).
Aerobic exercise intensity will vary from person to person, but generally you should strive to perform moderate-intensity exercise, which corresponds to an exertion level of 5 or 6 on a 10-point scale (see chapter 5 for more information on intensity). Several points regarding intensity need to be emphasized (1). If you have been diagnosed with chronic angina by a health care provider and the provider is aware that you have some chest discomfort with exercise, the recommendation will likely be to keep your heart rate 10 beats below the chest discomfort threshold (2). Medications such as beta-blockers can lower your resting heart rate and lower your heart rate response to exercise. If you take these medications, you may not be able to achieve a high heart rate during exercise. Don’t worry, though—you will still derive benefit from the exercise session and can focus on your perception of effort rather than heart rate (3). Medications such as diuretics (so-called water pills) can cause some individuals to become volume depleted, can alter electrolyte levels such as potassium, and can cause some to feel dizzy when they stand up or after an exercise bout. Your health care provider will regularly check your electrolyte levels, but you should let your doctor know if you get dizzy or light-headed after an exercise bout (2).
A general recommendation for exercise session duration is between 20 and 60 minutes, although you can begin with only 5 to 10 minutes per session and then gradually build up. If you are interested in weight loss, you probably want to get as close to 60 minutes per session as you can in order to maximize the calories that you burn. Also, you can strive for one continuous session or several sessions of at least 10 minutes each throughout the day (2).
Aerobic activities should form the backbone of your exercise routine. A reasonable goal for most adults is to expend about 1,000 calories (kcal) per week with the aerobic exercise program (or higher if your goal is to lose weight) (see chapter 5 for steps to calculate the number of calories burned). This will vary depending on your weight, and it is important to emphasize that you will derive health benefits even if you are well below this value. No standard rate of progression is recommended for all individuals. The key is that the rate of progression for intensity and duration be should gradual to avoid injury (2).
Another way to reduce the risk of injury is to ease into and out of your exercise session. Warm-up should consist of low-intensity activities for approximately 5 to 10 minutes, typically doing the conditioning activity at a lower intensity than during the conditioning phase. An example is a period of slow walking prior to engaging in a more brisk pace for the conditioning phase. Following the conditioning activity, a cool-down should consist of low-intensity activity for approximately 5 to 10 minutes. Stretching and range of motion activities can also be incorporated into the warm-up or cool-down but should follow rather than precede the light activity.
The focus in this section thus far has been on aerobic exercise training, but it is important to highlight that resistance exercise training is also recommended on two to three days per week for individuals with CVD. Resistance exercise training should be included for improved muscle strength; however, isometric exercises (exercises in which a contraction is maintained or held in one position) should generally be avoided because they can lead to excessive increases in blood pressure. The intensity should generally be moderate. Remember to breathe normally while lifting (i.e., don’t hold your breath when lifting). For those with high cholesterol or high blood pressure, typically two to four sets of 8 to 12 repetitions for each of the major muscles groups are recommended (2). For additional information on resistance training and examples of exercises for the various muscle groups, see chapter 6.
Flexibility training is also beneficial for all adults, including those with CVD. In addition, although there are no recommendations unique to persons with CVD, inclusion of neuromotor exercise may be considered as part of a general exercise program. More information on flexibility and neuromotor exercises is presented in chapters 7 and 8 (2).
Q&A
Are there any special exercise considerations for those with high cholesterol or high blood pressure?
The general principles of the exercise prescription detailed in this chapter also apply to individuals with dyslipidemia (i.e., high cholesterol). However, typically, healthy weight maintenance is emphasized for individuals with high cholesterol. This means that caloric expenditure during the exercise session should be increased; in general, this is accomplished by exercising five or more days per week (rather than only three times) and exercising for 50 to 60 minutes per session (rather than 20 to 30 minutes).
Individuals with high blood pressure also benefit from regular exercise. Each exercise session can lead to a reduction in blood pressure; therefore near-daily or daily exercise is recommended (five to seven days per week). Moderate exercise intensity is also recommended; high-intensity exercise is not needed to derive the blood pressure–lowering effect of exercise. However, since blood pressure can decline immediately after exercise, an active cool-down is important to prevent blood pressure from declining too much.
While the focus of this section is on the components of a structured exercise program, it is important to adopt a physically active lifestyle in general. Sedentary behaviors (i.e., a lot of sitting) can be detrimental, even in people who exercise regularly. Pedometers are one way to help promote regular physical activity, and most guidelines suggest a reasonable goal of 5,400 to 7,900 steps per day (2).
Influence of Medications
Sometimes lifestyle changes—the front line in cardiovascular risk reduction—are just not enough. You may need adjunctive drug therapy to better control certain risk factors. Of course, taking medication(s) does not take the place of the positive lifestyle modifications discussed in this chapter. Keep focused on heart-healthy nutrition choices and regular physical activity, understanding that medications may be needed in addition to those lifestyle behaviors to achieve goals.
Although a detailed description of cardioprotective drugs is outside the scope of this chapter, this section discusses medications used to address high cholesterol and high blood pressure. With any medication, additional considerations are the potential for interactions with food or other medications and for side effects or adverse reactions. Because of the complexity of this issue, ongoing consultation with your health care provider and pharmacist is recommended.
Lipid-Lowering Medications
Various types of drugs can be used to lower cholesterol, and they act on the body in differing ways. Many of the lipid-lowering drugs affect activity in the liver, so liver function should be routinely checked as a precaution against liver damage. One class of lipid-lowering medications is the statin drugs. Statins are powerful medications used to treat high blood cholesterol levels. These drugs block cholesterol production in the liver. Because the body needs a certain amount of cholesterol to function, it compensates by drawing on cholesterol present in the bloodstream. This reduces the amount of cholesterol that could damage arteries. Statins do have a downside. In rare cases, statins can cause elevations in some liver enzymes and ultimately result in liver damage. Thus, patients who use statin medications should have their liver enzymes evaluated once or twice yearly. In addition, statins are associated with muscle inflammation, a condition called rhabdomyolysis. The usual complaint is muscle soreness or pain. When someone who is exercising is taking a statin, muscle discomfort or pain may be a result of the medication and not the exercise. If you take a statin and notice any uncommon muscle discomfort or pain, report it to your health care provider.
Blood Pressure–Lowering Medications
Health care providers use several classes of medication to lower blood pressure, and most individuals with hypertension take more than one to control blood pressure. Beta-blockers are one such medication. In addition, beta-blockers are used to relieve angina (chest discomfort) and to ward off heart rhythm disturbances. Beta-blockers decrease the work of the heart by inhibiting the activity of the sympathetic nervous system, which is responsible for increasing heart rate and blood pressure. Thus, both heart rate and blood pressure are suppressed in individuals taking beta-blockers. As a result, heart rate ranges are often not used to set intensity. An option to consider is the use of the relative scale (e.g., working at a level 5 on a 10-point scale) as discussed in chapter 5.
Other common medications used to help lower blood pressure include the following:
· Diuretics, commonly referred to as water pills, which increase urine output
· Angiotensin-converting enzyme (ACE) inhibitors, which block the production of a hormone that can elevate blood pressure
· Calcium channel blockers, which relax blood vessels
These medications lower blood pressure through different mechanisms of action. How each person responds to a given medication varies, so your health care provider will choose the most appropriate medication(s) for you. Your response will be monitored, and often dosage or type of medication will be adjusted to achieve blood pressure goals.
As reviewed in this chapter, a healthy diet and regular physical activity are both critical to achieve optimal cardiovascular health. Positive lifestyle choices are especially important for those with CVD, including heart disease and stroke. Proper diet and regular exercise favorably influence multiple risk factors and therefore lower your risk for disease. Adopting a healthy lifestyle will cause you to feel better, have more energy, and have an improved quality of life.