Planning a heart-smart exercise program
When developing an exercise program, you should consider the following fitness components: cardiovascular fitness, muscular fitness, flexibility, and body composition.
Cardiovascular fitness, also referred to as aerobic fitness or aerobic capacity, is developed by focusing on exercises that enhance the function of your heart, circulatory system, lungs, and skeletal muscles all at the same time. When cardiovascular fitness is high, so is aerobic capacity. For maximum effectiveness, cardiovascular conditioning should include exercises that are rhythmic, continuous, and involve the large muscle groups (primarily located in the lower part of your body). Walking, jogging, cycling, aerobic dance, and stair climbing are examples of exercises that use large muscle groups and can enhance your heart function, cardiovascular fitness, and aerobic capacity. Activities combining upper- and lower-body movements such as cross-country skiing, rowing, walking, jogging, running, and swimming can lead to even higher aerobic capacity.
Muscular fitness is enhanced by resistance training. Here the focus of the exercise is to enhance skeletal muscuar strength and endurance. Exercises used in this type of training can emphasize strength, endurance, or both. When your goal is to increase strength and size of muscles, you should lift a weight 6 to 8 times, or repetitions (reps), before becoming fatigued to the point that you are unable to continue. On the other hand, if your goal is to increase muscular endurance, you should lift a weight 12 to 15 reps before fatiguing.
There are two facts to keep in mind. First, unless muscular strength and endurance exercises are performed regularly, you will lose up to half a pound of muscle for every year of life after age 25. Second, muscle is very active tissue with high energy requirements. Even when you are asleep, your muscles are responsible for more than 25 percent of your body’s use of kilocalories. An increase in muscle tissue causes a corresponding increase in the number of kilocalories your body burns, even at rest.
Flexibility is the ability for muscles to move joints through their full range of motion, and it is a critical element that is often overlooked in exercise programs. Being able to use a joint’s full range of motion can increase physical performance, decrease risk of injury, increase that particular joint’s blood supply, improve balance, decrease risk of pain such as in the low back, and reduce muscular stress.
Body composition is also a component of physical fitness and refers to the two basic tissues found in the body: lean mass (muscle, bone, vital tissues, and organs) and fat mass. An optimal ratio of fat to lean mass is used by some as an indication of fitness, and with the right amount of appropriate exercises you can decrease body fat while increasing muscle mass.
A planned exercise session has three basic components: the warm-up, the cardiovascular fitness and muscular fitness portion, and the cool-down. Each of these components can vary in length depending on what your goals are.
The warm-up is the first part of the exercise session. It is important because it increases the body’s temperature. A common mistake made by many people just starting an exercise program is overstretching or doing too many range-of-motion exercises before the muscles are adequately warmed up. Never stretch a cold muscle; rather, warm up the body by doing light aerobic exercises. The best time to stretch your muscles is after they are warm. One way of warming the body is by doing the same activity that you do during the cardiovascular fitness portion of the exercise session, but at a much lower intensity. This warm-up exercise can be an easy walk or an activity at less than 40 percent of your maximum heart rate (HRmax). The warm-up should last from 5 to 10 minutes. After finishing your warm-up exercises, your muscles should be warm, which may help prevent injury.
The cool-down portion of an exercise session is similar to the warm-up in that it should last 5 to 10 minutes and should be done at a low intensity (40 to 50 percent of HRmax). After you have completed the cardiovascular and muscular fitness portion of the session, the cool-down portion begins. This part of the exercise session is extremely important for developing flexibility because it is where you gain the most benefits from flexibility and range-of-motion exercises. With increased flexibility, your performance levels are likely to be higher and your injury risk reduced. Later in the chapter we’ll describe and illustrate some effective flexibility exercises.
Range-of-motion and flexibility exercises are best performed moving through the full range of motion slowly. When you reach the farthest point in the movement, hold at that point for six to eight seconds. This form of stretching is referred to as static stretching and is different from ballistic stretching. Ballistic stretching uses the same stretching position, but movement is performed faster and is not held when the farthest movement point is reached. As a result, the movement looks as though bouncing is incorporated, which is why it is called ballistic stretching. This form of stretching can cause tears in the muscle tissue and other tissue damage and is not recommended.
It is a good idea to add two exercises to the cool-down: push-ups and abdominal curls. These are not flexibility exercises — instead they enhance strength and endurance — but they take little time and can be done without any added expense. Doing push-ups increases the tone of the muscles in the upper extremities, including the pectoral, deltoid, biceps, and triceps muscles. Abdominal curls will increase the tone of the muscles in the abdominal area, including the rectus abdominis and external obliques.
Whether your interest is in cardiovascular fitness or muscular fitness, four keys to selecting the right kinds of exercises for each of the basic components of fitness are found in the following principles.
• Overload. This principle implies that you must work at a level of moderate to vigorous exercise intensity long enough to overload your body above its resting level in order to bring about improvement.
• Progression. This principle means that when starting an exercise program, it is better to start at lower intensity, frequency, and duration and over several weeks or months slowly progress to higher exercise intensities of longer durations and at a greater frequency.
• Specificity. Exercise training is specific, and this principle means that you need to select the type of activities that will help you meet your long-term goal. For example, because one of your goals is to reduce blood cholesterol and because the best way to positively affect blood cholesterol is to choose activities that improve cardiovascular fitness, you need to select activities like walking, running, or biking. An exercise program that primarily focuses on muscular fitness is not the best program for moving toward your goal of achieving a healthy blood lipid and lipoprotein profile.
• Reversibility. You can’t save up cardiovascular fitness. Once you have reached a desirable fitness level, at least two or three exercise sessions a week are necessary to maintain the achieved fitness level.
From Action Plan for High Cholesterol by J. Larry Durstine, PhD.
Excerpted by permission of Human Kinetics, Champaign, IL. Available to order at www.HumanKinetics.com or by calling 1-800-465-7301.