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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:

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:

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:

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:

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

Drugs and High Blood Pressure

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