Exercise and age: Prescription for mature adults

by Tyrone M. Reyes, M.D.

People who say that exercise keeps them young may be more correct than skeptics think.

Research now suggests that much of the decline once attributed to aging is actually due to long-term inactivity. Obviously, age and certain medical conditions can affect one’s ability to do particular kinds of strenuous exercise.

But if you can walk, you can reap the benefits of regular activity, from blood pressure control to increased longevity.

These are strong arguments for people of all ages to keep moving. The list of exercise’s benefits is long and getting longer: It helps to maintain a healthy weight, increases levels of HDL (the “good” cholesterol), protects against diabetes, enhances muscle strength and balance (which minimizes accidental falls), wards off depression and anxiety, helps to prevent osteoporosis, and reduces the risk of certain cancers.

Getting Started

So, how much exercise should an older person do, and which types of exercise are best? Most experts now agree that, as people age, they need to be involved in a comprehensive exercise program that includes both aerobic and resistance training.

Aerobic (or endurance) exercise leads to improved cardiovascular fitness. This type of exercise includes walking, running, cycling, dancing, rope skipping, rowing, swimming, stair climbing, and skating. In short, these are exercises that make your heart beat faster and speed up your breathing. In contrast, resistance exercise (also called strength training or weight training) strengthens the muscles, tendons, and ligaments, and may help promote flexibility. The use of free weights (dumbbells), wall-mounted pulleys, resistance bands, or exercise machines are examples of resistance exercise.

Most people can start a walking program without any medical advice. If you plan to do something more vigorous than walking, ask your doctor for a checkup. Some experts recommend that previously inactive men and women over 40 have an exercise stress test before starting a vigorous exercise program (such as jogging or running). Many physicians though reserve these tests for people with a history of chest pain, those who may have heart disease, those with major risk factors for heart disease, such as high blood pressure or cholesterol, obesity, or smoking. Talk with your doctor before starting a strength training program. He/she might suggest an exercise stress test or another procedure to check your heart and help you set some goals or limits for your first exercise sessions. It’s especially important to check with your doctor if you have unstable angina, uncontrolled high blood pressure, uncontrolled irregular heart rhythms, uncontrolled heart failure, or hypertrophic cardiomyopathy.

Pacing Oneself

An important part of any exercise program is setting realistic and safe goals. The degree of aerobic activity that will improve physical conditioning varies from person to person — some may be ready to start jogging up and down hills, but most should begin with walking.

• Maximum heart rate (HRmax). This term refers to the fastest speed that a person’s heart can beat. You can estimate your HRmax by subtracting your age from 220. For example, the maximum heart rate of a 65-year-old person would be approximately 220 minus 65, or about 155 beats per minute. Most experts recommend that people exercise at between 50 and 75 percent of their maximum heart rate — a range called the target heart-rate zone. For example, for physical activity to benefit the heart and lungs of the average 65-year-old individual, his/her heart should beat at least 78 times per minute (155 multiplied by .50) but not more than 116 (155 x .75) while exercising.

You can measure your heart rate by placing the tips of the first two fingers lightly over the largest artery in the neck (the carotid), located to either side of the Adam’s apple, or on the inside of the wrist below the base of the thumb (radial artery). A high-tech alternative is to buy an electronic rate monitor that uses sensors to track the heart rate. These devices are sold in sporting-goods or health stores.

• Rate of perceived exertion (RPE). People usually have a pretty good idea of how hard they are pushing themselves so it is not surprising that they can learn to recognize when they are exercising harder than is safe. The RPE scale is based upon asking people how intense their level of exertion is on a scale of 6 to 20. On this scale, very light exercise is under 10 points and very heavy is over 15. By learning to recognize what exertion level corresponds to a heart rate in your target zone, you can monitor your exercise intensity and adjust it accordingly. Another easy way to monitor your level of exertion is by talking while exercising. You should exercise hard enough so your heart and breathing speed up, but not so hard that you can’t carry on a conversation.

Easy Does It

A wise strategy for someone beginning a regular program of physical activity is to start by taking a 15-minute walk at least three times a week — building up to every day, if possible. Walking with an “exercise companion” makes the experience more fun and helps emphasize its importance. The first five minutes of the walk should be taken at a moderate pace. This “warm-up” period should be followed by brisk walking for five minutes so that the heart reaches its target heart zone. During the final five-minute cool-down period, the pace should be slower again. In the following week, brisk-walking time can be increased by two to five minutes (keeping the warm-up and cool-down periods at five minutes each), and in subsequent weeks, it can be gradually increased until you are walking 30-60 minutes.

If you have been inactive for six months or more or have physical or medical limitations — such as angina (the chest discomfort that indicates the heart is not getting enough blood) or lung disease — be even more conservative. Start with a shorter walk of five to 10 minutes and add one minute or less every two to three exercise sessions. Regularity and frequency are key components of any exercise program. The more you participate during a week, the more weeks per month, and the more months per year, the more health benefits you will acquire. Naturally, if pain, discomfort, or troublesome shortness of breath occurs, stop exercising immediately and call your doctor.

Resistance Training

Cardiologists once thought weight lifting and other resistance-training exercise raised blood pressure and caused heart-rhythm abnormalities. So heart patients were advised to avoid lifting, pulling, and pushing. But over the past decade, several studies have demonstrated the benefits of this type of exercise and documented its safety — as long as you do not attempt to lift extremely heavy weights and don’t hold your breath. Today, resistance exercises are recommended not only for healthy adults but also for those with heart disease.

An effective weight-training program usually includes eight to 10 exercises that train the major muscle groups of the body — arms, shoulders, chest, abdominals, back/trunk, hips and legs. This type of exercise should be done a minimum of twice a week with at least one day’s rest between sessions. Start with a very light weight that you can control comfortably. As you master the technique and gain strength, you can gradually increase the load or the number of repetitions. A good rule of thumb is to repeat each exercise 10-15 times until the muscles are moderately fatigued. Proper breathing is very important because it reduces the chance of temporary increases in blood pressure and allows you to do more repetitions. When you lift a weight, you should exhale; when returning to the starting position, you should inhale.

If you don’t know how to start an exercise program, ask your doctor to recommend a fitness facility or fitness specialist who can help design a regimen appropriate for you. If you already have a cardiac disease, ask your doctor if a cardiac rehabilitation program might be suitable.

Never Too Late

No one should be deterred from pursuing exercise because of age. Research has shown that even people who begin exercising in their 90s and 100s realize gains in both cardiovascular and musculoskeletal fitness. Nevertheless, older individuals should start gradually. And anyone performing strength-training activities should avoid exercise of such intensity that it causes pain, which may lead to (or indicate) muscle strains, tears, or other orthopedic injuries. Because of the proven benefits of even moderate activity, just about every authoritative document on exercise guidelines recommends that most adults pursue moderate-intensity training.

Yes, it’s never too late to start an exercise program and even a little bit of exercise is better than none at all!

Source: Philippine Star