Heart Disease and Exercise

The development of coronary artery disease is greatly influenced by lifestyle factors such as diet, physical activity, stress and smoking. High blood pressure, high cholesterol and diabetes also increase the risk. Heart disease ranks as the number one cause of death in the US, and it is also the number one cause of death in the elderly. Coronary artery disease (CAD) is the primary type of heart disease experienced in the elderly.

Cardiac rehabilitation is offered after a myocardial infarction, or heart attack. There are three stages to rehabilitation. In Stage 1, the patient works with the rehabilitation team while still in the hospital. Stage 2 is done on an outpatient basis after the patient has gone home but is still under supervision at the hospital. Stage 3 is an individual program that the patient follows independently at home. You will often acquire new clients with heart disease after they have had a “wake up call” in the form of a heart attack. Open communication with the doctor is important to ensure that the client has been released from the formal rehab program and to learn what limitations still exist. Fortunately, cardiologists usually give you specific guidelines for exercise. This is not often true for the internist or primary care doctor who might not have as much background or regard for physical activity.

The typical symptoms of CAD include chest pain and difficulty breathing. Older people sometimes do not experience any chest pain, but they do experience trouble with breathing. There is also decreased exercise tolerance and chronic fatigue. If your clients suffer from chronic fatigue, consistent exercise will actually eventually increase energy and endurance.

As you continue to read on, you will probably agree that most of the guidelines or special needs identified for people with heart disease are good general guidelines to adhere to when training almost all seniors. These include the following:

• Persons with systolic blood pressure greater than 180 mm Hg or a diastolic pressure greater than 110 mm Hg should not begin an exercise program until blood pressure is normalized with medication.
• The signs of an emergency include chest pain, irregular heartbeat, difficulty breathing and dizziness. Watch skin color, respiration rate, heart rate and blood pressure, and be vigilant about asking for RPE and general reactions to exercise (i.e., how are they feeling?).
• You should avoid exposure to extreme heat or cold as this can put undue stress on an aging body that is already more sensitive to heat and cold.
• Your client should not eat a large meal before exercising. There should be at least two hours between a large intake of food and an exercise routine.
• Ask your clients if they have taken their medications for that day and check their blood pressure and heart rate before exercise.
• Do not allow them to exercise if their blood pressure is 20 mm Hg (systolic) higher than usual.
• Use the Rating of Perceived Exertion (RPE) scale to measure intensity for clients who are on medication. Medications can change the heart rate response to exercise.
• Individualized exercise programs are recommended for people with heart disease because it is important to watch them closely for possible signs of trouble. Save the group exercise until after these clients have progressed to a certain level and you are comfortable with their status.
• Avoid isometric exercises for patients with high blood pressure.
• Do not allow your client to hold the weight or resistance in one spot. Keep it moving because holding it in place can increase blood pressure to dangerous limits.
• Avoid allowing clients with high blood pressure to hold a weight above their heads as this can increase blood pressure beyond safe limits. In fact, avoid “over-the-head” exercises that use weights with all seniors.
• Make sure your clients breathe continuously since breath holding while performing resistance exercise can produce seriously high blood pressures. Have clients count repetitions out loud with you. This will keep them from holding their breath.
• Use higher repetitions (12 to 15) and lighter weights for strength training. If the physician has given you specific HR maximums, follow the “four beats per repetition at 70 percent” rule that you will learn about later in this article.
• Steady state aerobic exercise should strive for 75 percent of maximum heart rate unless the doctor says otherwise.
• High intensity exercise should be discouraged.
• The client should always warm up slowly and avoid sudden movements and/or changes in position.
• Offer frequent rest periods. Don’t let clients overexert themselves.
• Always cool down as long as needed to allow the heart rate to return to normal levels. Don’t let clients rush away before their heart rates have returned to normal.
• Be careful if a client’s heart rate remains elevated longer than usual. This might indicate a necessity to lighten the client’s program. If the client is on the same program that has been established for a while and you have not made any recent changes, a prolonged elevated heart rate might indicate that a trip to the doctor is in order.

Cardiovascular Response During Strength Training 

Whenever a person performs physical activity, heart rate and blood pressure increase in proportion to intensity. Because of this cardiovascular response to exercise, there is concern when working with cardiac rehab patients. American College of Sports Medicine (ACSM) guidelines recommend 60 to 90 percent maximum heart rate for endurance exercises. The most common recommendation is 75 percent, a safe level for most post-coronary clients. Steady-state aerobic exercise at 75 percent of maximum heart rate will most likely elevate systolic pressure to about 160 mm Hg, or about 35 percent above normal resting levels. That level should be maintained for the duration of the steady-state exercise.

It has long been assumed that strength training causes excessively high blood pressure responses. According to research done by Dr. Wayne Westcott and his colleagues, however, this is not true as long as the exercises are performed properly. In fact, Dr. Westcott found that upper body strength exercises performed to the point of fatigue produced similar responses to aerobic activity. A dumbbell curl performed at 75 percent of 1RM to fatigue produced blood pressure increases of about 35 percent at the point of fatigue.

Although working with larger muscles of the lower body results in higher systolic blood pressures, Dr. Westcott’s research revealed that the responses were well within safe limits. In a study he conducted where participants performed 10 repetitions on a leg press to the point of fatigue, the systolic pressure increased to about 50 percent above resting levels at the point of fatigue. The average resting pressure was 127 mm Hg and the average peak systolic pressure was 190 mm Hg, which is far below the ACSM exercise guideline of 225 mm Hg. Following the final repetition, blood pressure actually returned to resting levels within about one minute.

The results of Dr. Westcott’s studies show that properly performed strength training does not cause excessive or dangerous heart rate response. “Performing exercises properly” means that we must focus on two major factors: continuous breathing and continuous movement.

While it is not practical to monitor a client’s blood pressure while strength training, it is relatively easy to measure heart rate. Since heart rate and systolic pressure both increase proportionately, when you know one, you can estimate the other. In another study conducted by Dr. Westcott, he researched the heart rate response to strength training at two levels of resistance. The subjects performed both upper and lower body strength exercises at 70 and 85 percent of maximum resistance to fatigue. On average, they completed about 14 reps at 70 percent and seven reps at 85 percent of 1RM. In both cases, the participants’ heart rates increased to 123 bpm. This represented about 50 bpm above the resting rate and just under 70 percent of their predicted maximum heart rate.

Although both resistance levels produced the same increase in heart rate, the increase per rep was considerably higher with the heavier weight. At 70 percent maximum resistance, the heart rate increased about four bpm, while at 85 percent maximum resistance it increased seven bpm. Because the heart rate increases more gradually when training with 70 percent rather than 85 percent, it would seem wiser to use the lower weight load for post coronary patients. Actually, this might be a wise move for anyone who has risk factors for heart disease or who is frailer than the average person.

Let’s look at a specific example of how you might be able to use this information. You have a client whose doctor has requested that you not exceed 50 percent of his maximum heart rate, which in this case is an increase of about 40 bpm. If we have this client do 10 repetitions at 70 percent of his repetition maximum, his heart rate should rise about 40 bpm. Remember, each repetition at 70 percent will increase heart rate by four bpm and 10 multiplied by four equals 40. Thus, 40 is our target number. Understanding this process will give you an easy and reliable way to stick to any guidelines or restrictions you are given for clients with cardiac conditions.

Heart Attack

Fast action is the best weapon against a heart attack. Why? Because clot-busting drugs and other artery-opening treatments can stop a heart attack. Although they can prevent or limit damage to the heart, they need to be given immediately after symptoms begin. The sooner they are administered, the more likely they will succeed and the greater the chance for survival and full recovery. To be most effective, medications need to be given within one hour of the onset of heart attack symptoms.

People expect a heart attack to happen just as it does in the movies, where someone clutches his chest in pain and falls over. Well, expectations don't always match reality when it comes to heart attack. As a matter of fact, many people are totally unaware of the fact that they are having a heart attack. As a result, they take a wait-and-see approach instead of seeking immediate care. This even happens to people who have previously experienced a heart attack because the symptoms of a second episode might actually differ from those that occurred during the first.

Many heart attacks are preceded by warning signs that begin well before the actual heart attack occurs. The symptoms include mild pain or discomfort and might even come and go.

It is vital that everyone learn the warning signs of a heart attack:

• Anyone showing heart attack warning signs needs to receive medical treatment immediately. Don’t wait more than five minutes at most to call 9-1-1.
• Chest discomfort. Most heart attacks involve discomfort in the center of the chest that lasts for more than a few minutes, or the discomfort might come and go. This discomfort can feel like pressure, squeezing, fullness or pain.
• Discomfort in other areas of the upper body. This can include pain or discomfort in one or both arms, the back, neck, jaw or stomach.
• Shortness of breath. This often accompanies the chest discomfort, but it also can occur before chest discomfort.
• Other symptoms. These include breaking out in a cold sweat, nausea or light headedness.

The first step to take when a heart attack is suspected is to call 9-1-1. Call even if you are not sure if someone is having a heart attack. Calling 9-1-1 for an ambulance is the best way to get to the hospital because:

• Emergency medical personnel (also called EMS or emergency medical services) can begin treatment immediately or even before arrival at the hospital.
• The heart can stop beating during a heart attack. Emergency personnel have the equipment needed to restart the heart.
• Heart attack patients who arrive by ambulance tend to receive faster treatment upon arrival at the hospital.

Delay can be deadly. Waiting too long to seek medical attention can be a fatal mistake. Patient delay, rather than a delay in transport to a treatment facility or delay at the hospital, is the biggest cause of not getting rapid care for heart attacks. Women, older adults and minorities are usually more likely to delay seeking help than other groups of people. People often take a wait-and-see approach because they:

• Do not understand the symptoms of a heart attack and think that what they are feeling is due to something else.
• Are afraid or unwilling to admit that their symptoms could be serious.
• Are embarrassed about “causing a scene” or going to the hospital for a false alarm.
• Do not understand the importance of getting to the hospital right away.

As a result of this wait-and-see approach, most heart attack victims wait two hours or more after their symptoms begin before they seek medical help. Not only can this delay result in death, but it can also lead to permanent heart damage, an effect that can greatly impair the ability to do everyday activities.

Drugs and Heart Disease 

Heart disease medications and high blood pressure pills present the greatest obstacles and difficulties when it comes to regular exercise. The heart disease medications that you will most commonly deal with are beta-blockers and diuretics. Beta-blockers slow down the heart rate and decrease blood pressure by blocking catecholamine released from the autonomic nervous system. Common names for beta-blockers are Inderal, Corgard and Lopressor. These medications can cause depression, fatigue and dizziness, all of which make exercise difficult. Remember, since beta-blockers decrease heart rate, HR measures are not valid indicators of exercise intensity for clients taking them. In these cases, RPE is recommended.

Diuretics are used to treat hypertension and congestive heart failure. They increase the secretion of sodium and chloride in the urine, which leads to fluid loss. Since water is a major constituent of blood, it contributes greatly to blood volume. Blood volume, in turn, has a direct impact on blood pressure. Consequently, any significant changes in the amount of body fluids will affect blood pressure, so blood pressure is reduced as a result of water loss. Clients who are taking diuretics usually need to use the bathroom more frequently. Be aware that this loss of fluid through diuretic use coupled with the fluid lost from exercise can easily lead to dehydration. Remember to monitor the client’s fluid intake and allow for adequate water consumption and restroom breaks. Common brands of diuretics include Lasix, Aldactone, Esidrix, Hydrodiuril, Oretic and Thiuretic.

Because high blood pressure is treated by decreasing the amount of fluid in the body, there is the possibility of postural hypotension. This occurs when the blood pressure suddenly drops after standing up too quickly and might lead to dizziness or loss of consciousness. Another problem that can develop with the use of diuretics is due to a depletion of the body’s potassium stores, a condition called hypokalemia. This condition causes weakness and fatigue. If you have a client who takes a diuretic and is complaining of theses symptoms, suggest a consultation with a doctor.

Medications are sometimes needed to help prevent or control coronary heart disease (CHD) or to reduce the risk for a first or a repeat heart attack. Even if medications are needed, however, lifestyle changes still must be undertaken. As you will see, some of the medications listed for CHD are also used to lower blood pressure since many people with heart disease already have high blood pressure. Remember, high blood pressure itself is a risk factor for heart disease.

Drugs and CHD

• Aspirin - Helps lower the risk of a heart attack for those who have already had one. It also helps to keep the arteries open in those who have had a previous heart bypass or other artery-opening procedure such as coronary angioplasty. Because of its risks, aspirin is not approved by the Food and Drug Administration for preventing heart attacks in healthy individuals. It might actually be harmful for some people, especially those with no known risk of heart disease. Thus, everyone must be assessed carefully to make sure the benefits of taking aspirin outweigh the risks.
• Digitalis - Makes the heart contract harder and is used when the heart's pumping function has been weakened. It also slows some fast heart rhythms.
• ACE (angiotensin converting enzyme) inhibitor - Stops the production of a chemical that makes blood vessels narrow. It is used to help control high blood pressure and damage to the heart muscle and might be prescribed after a heart attack to help the heart pump blood more efficiently. It is also used for people with heart failure, a condition in which the heart is unable to pump enough blood to supply the body's needs.
• Beta blocker - Slows the heart rate and makes it beat with less contracting force, so blood pressure drops and the heart’s work load decreases. It is used for high blood pressure and chest pain and to prevent a repeat heart attack. This is the main medication that you will encounter. It makes measuring exertion levels by heart rate inaccurate because it slows the heart rate.
• Nitrates (including nitroglycerine) - Relaxes blood vessels and stops chest pain.
• Calcium channel blocker - Relaxes blood vessels and is used for high blood pressure and chest pain.
• Diuretic - Decreases fluid in the body and is used for high blood pressure. Diuretics are sometimes referred to as “water pills.”
• Blood cholesterol-lowering agents - Decrease LDL cholesterol levels in the blood.
• Thrombolytic agents - Also called “clot busting drugs,” these are given during a heart attack to break up a blood clot in a coronary artery in order to restore blood flow.

Drugs and High Blood Pressure

• Diuretics - Sometimes called “water pills” because they work in the kidney and flush excess water and sodium from the body.
• Beta-blockers - Reduce nerve impulses to the heart and blood vessels. This makes the heart beat slower and with less force. Blood pressure drops so the heart doesn’t have to work as hard. It makes measuring exertion levels by heart rate inaccurate because it slows the heart rate.
• Angiotensin converting enzyme (ACE) inhibitors - Prevent the formation of a hormone called angiotensin II that normally causes blood vessels to narrow. The ACE inhibitors cause the vessels to relax so blood pressure drops.
• Angiotensin antagonists - Shield blood vessels from angiotensin II. As a result, the vessels become wider and blood pressure drops.
• Calcium channel blockers (CCBs) - Keep calcium from entering the muscle cells of the heart and blood vessels. This causes the blood vessels to relax so that pressure drops.
• Alpha-blockers - Reduce nerve impulses to blood vessels that allow blood to pass more easily so blood pressure drops.
• Alpha-beta-blockers - Work in the same manner as alpha-blockers, but they also slow the heartbeat like beta-blockers do. As a result, less blood is pumped through the vessels and the blood pressure drops.
• Nervous system inhibitors - Relax blood vessels by controlling nerve impulses. This causes the blood vessels to become wider and the blood pressure to go down.
• Vasodilators - Open blood vessels by relaxing the muscle in the vessel walls, which causes the blood pressure to drop.

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