Exercise and Heart Disease

StethoscopeDear Chris,

Am I more prone to heart attacks and other coronary issues if I exercise when I’m older?

Steve in Toronto

Dear Steve,

Engaging in cardio-respiratory or aerobic exercise will actually reduce your chances of having a heart attack or developing coronary Heart Disease. This type of exercise will make your heart stronger, help reduce your resting blood pressure, and keep your circulatory system running smoothly. However, this type of exercise does come with some risks and reducing those risks depends a great deal on your overall health. The risk of developing coronary heart disease or having a heart attack does increase with age. However, the conditions that lead to coronary heart disease are more related to lifestyle factors (and sometimes genetic ones) than to the aging process itself. Often people don’t know they have coronary heart disease until they suffer a heart attack, especially if they had not exhibited symptoms like angina before or were never diagnosed with it.

That being said, there is a small risk of suffering a heart attack while exercising. There are definitely things you should keep in mind when starting an exercise program at any age but especially as you get older. If you’ve been sedentary or are overweight, chances are your heart is not as healthy as it should be. You should first see your doctor and let him or her know that you want to be more active. He or she may order a stress test to determine what your target heart rate should be. If your doctor has some concerns, he or she may give you a safe target heart range within which to exercise. Otherwise, there is a formula you can use to calculate it (see below). Either way, proceed slowly.

If you haven’t been active, don’t try to make up for lost time and jump into your program full force. Unless your doctor has given you other instructions, warm up for 5-10 minutes first at the low end of your target heart rate zone (see below). As your body warms up and your heart gets ready to exercise at a stronger intensity, you can gradually bring your heart rate up higher. Much of what you determine to be a safe exercise intensity zone will depend on your own health as well as medications you may be taking (some medications can affect your heart rate).

There are different ways to calculate your target heart rate zone. Here’s a common and conservative way, ideal for beginners:

  • First, subtract your age from 220. This will give you your age-predicted maximum heart rate. For example, if you are 65, then your age-predicted maximum heart rate is 155 beats per minute (220-65).
  • The lower limit is generally 60% of this number. For a 65-year old, this would be 93 beats per minute (155 times 60%). Your warm-up heart rate should not exceed this lower limit, and in any case should never exceed 100 beats per minute.
  • The upper limit is generally 80% of the age-predicted maximum heart rate — in this case, 124 beats per minute (155 times 80%). You should not work out above this rate.

Using a target heart rate zone is only one way of determining safe exercise intensity levels. There are other measures such as the Talk Test and the Rate of Perceived Exertion. When I am working with clients, I always ask them to say a sentence out loud (and I don’t mean two words!). During the warm-up, they should easily be able to speak conversationally. They should also describe their exercise intensity level as “light” on the Rate of Perceived Exertion scale (I’ll talk more about this in an upcoming column). Once they are past their warm-up and are exercising more intensely, they should need to take a breath at the end of a sentence but they should not be feeling uncomfortable (nauseous, dizzy, lightheaded). Similarly, they should describe their level of exertion as “somewhat hard” or “hard” on the Rate of Perceived Exertion scale.

The most important thing to remember is to give your heart a chance to get stronger gradually. It needs time to adjust to this new level of demand you have placed upon it. But with patience and perseverance, you will reap the benefits of a strong and healthy heart.

To your health

Chris


Information on stayingstrong.ca should not be used for diagnosis, nor should it be considered a replacement for consultation with a healthcare professional. If you have questions or concerns about your health, please contact your healthcare provider.

Not in the Mood

EmoticonsObesity and physical inactivity are widely accepted as major health hazards. Older women in the United States have been counted as one of the most obese and sedentary segments of the population. Unfortunately, the combination of being post-menopausal, obese, and sedentary has been cited as being a high predictor of developing cardiovascular disease. Many women recognize this in their own lives and take steps to reduce their dietary intake and be more physically active by joining behavioural weight loss programs (BWLP – see note below). However, many of these women find it hard to stick to their programs, especially over time. Researchers decided to study whether a person’s mood could affect their chances of sticking to their exercise program. (This is called ‘compliance’ in research terms.)

The researchers studied 25 obese, sedentary, post-menopausal women over the course of an eight-week behavioural weight loss program (see Sidebar). The participants completed a graded exercise test (GXT) before beginning the program. They also completed a questionnaire to assess their mood before and after taking the initial exercise test. Exercise can evoke strong negative or positive feelings, and the researchers knew that many sedentary and obese people had reported feelings of embarrassment, fear, or apprehension related to exercising. Assuming that a person’s mood immediately before exercising would reflect their general attitude toward exercising, the researchers wanted to know if this attitude would affect participants’ adherence to the exercise component of the BWLP.

The first pattern to emerge from this study was that those who reported a positive mood before the initial exercise test tended to engage in more planned exercise during the weight loss program. Mood made no difference in the amount of non-exercise daily physical activity that occurred. In other words, people had to be in the mood to exercise in order to follow a program, whereas domestic and vocational tasks were performed out of necessity and duty.

The second pattern to emerge was that the relationship between mood and the amount of exercise performed grew stronger over the course of the BWLP. Women who reported greater vigor before and after the test and less post-exercise confusion spent more time in planned exercise during the middle and final stages of the BWLP. In contrast, those women who reported greater fatigue and confusion after the test spent less time exercising in the final weeks of the BWLP. One explanation for this finding is that at the beginning of the BWLP, all of the participants were excited about the new program and pushed themselves to exercise regularly, regardless of their moods. However, over time, as the novelty of the program wore off, many found it difficult to stick to the exercise program. Only those who showed an elevated mood at the initial test (and therefore presumably had better feelings about exercise) were able to stick to it.

The researchers concluded that although exercise is seen as one of the most important factors in successful weight maintenance after weight loss, many women who enter formal weight-loss or physical activity programs may have poor treatment outcomes. Women with negative feelings about exercise might exercise less than women who are in a positive frame of mind. Recognizing the role of mood to exercise compliance might reveal motivational and cognitive clues that could be used to identify and promote physical activity in reluctant adults more effectively. Some people may benefit from programs that help them overcome their negative feelings or ambivalence towards exercise. Motivational techniques geared to decreasing emotional obstacles and resolving ambivalence to exercise may go a long way to improving the effectiveness of BWLP, which appear to have reached a plateau in the last decade.

What the study did not address was how to motivate people who are reluctant or ambivalent towards exercise to get active. What can you do if you hate exercising?

The first thing I tell new clients is that it takes time to build that motivation. The motivation is usually external at first. This is why so many people like to join a class or hire a personal trainer–so that they feel obligated to show up to a class, a small group, or a session with their trainer. A good personal trainer or fitness instructor will help you get motivated and more importantly stay motivated. A good instructor or trainer will ensure that you are exercising safely and effectively. By making a class or a session challenging and fun, you will learn to associate exercise with good feelings instead of bad. Over time and with practice, motivation becomes more internally driven. Remember that it takes time to form habits–good or bad ones. Exercise is no different. As you become more regular with attending classes, meeting with your trainer, or exercising on your own, a habit will form and be reinforced every time you do it. It’s important to be regular with your exercise schedule–by choosing which days and times are most suitable–and sticking with it. If your schedule has to change because of work or domestic responsibilities, don’t give up. Make a new exercise schedule and stick with that one for as long as you can. Most of all, learn to roll with the punches. Don’t throw in the towel because of unforeseen circumstances. Get back in the ring!

To your health,
Chris


Behavioural Weight-Loss Program

Behavioural Weight-Loss Program (BWLP) is a program that tries to help people lose weight by attacking the problem on many fronts. Over a six-month period, participants attend 16 to 24 sessions with nurtitionists, behavioural therapists, and exercise physiologists. They learn not only how to eat better and exercise safely, but also how to change the environment around their home to make it easier for them to exercise and eat better. For example, they learn to remove high-fat foods from their environment; how to organize their space to remind them to exercise (and make it easy to do so), how to deal with social situations that require eating, how to modify their own recipes, and even how to get back to the program after a relapse. Participants are even taught problem-solving and assertiveness techniques, to help them get past unexpected problems that may arise.


References

Carels, R. A., Berger, B., Darby, L. (2006) The association between mood states and physical activity in post-menopausal, obese, and sedentary women. Journal of Aging and Physical Activity, 14(1), 12-28.