The Importance of Physical Activity
Physical activity is defined as body movement produced by the skeletal muscles that results in energy expenditure. It is a crucial component of a healthy lifestyle. In fact, physical inactivity has been proven to be a major risk factor in the development of coronary artery disease. In addition, physical inactivity has been linked to other risk factors such as obesity, cancer, diabetes and high blood pressure.
Increased physical activity could help alleviate many of these conditions.
Benefits of Physical Activity
Just a moderate amount of physical activity can be beneficial to health and well-being. Benefits include:
All age groups can benefit from physical activity. Current recommendations state that children and adults should attempt to complete at least 30 minutes of moderate activity every day.
Target Heart Rates
Moderate exercise is defined as 50 to 75 percent of your maximum heart rate. This can be calculated by using the following formula: 220 ' (minus) your age x (times) percentage of effort desired. For example, if you would like to exercise at 50 percent of your heart rate and you are 25 years old: 220 - 25 x .50 = 97.5 beats per minute. This would be considered the low end of your target heart rate zone. At 75 percent of your maximum heart rate, your target heart rate would be 146 beats per minute. This would be considered the high end of your target heart rate zone.
Physical Fitness
Physical activity is important for health. The International Consensus conference on Physical Activity Guidelines for Adolescents recommended that adolescents should be physically active most days. This activity may take the form of games, sports, work, physical education, walking or biking to school or other places or planned exercise. When activity is incorporated in daily activities at home, at school and in the community, physical fitness is easier to achieve.
Components of Physical Fitness
There are five components of physical fitness. A sound exercise program should address the first four factors of physical fitness. The five components are
Aerobic Endurance
Aerobic endurance pertains to the body's ability to use oxygen. Aerobic endurance allows people to last longer when participating in activities such as running, walking, climbing stairs, riding a bike or swimming. The more aerobic endurance people have, the easier it is for them to participate in these activities.
People need aerobic endurance to achieve cardiovascular fitness-the ability to pump blood through the heart and blood vessels, thereby feeding the working muscles more fuel (oxygen) for work. When exercising for aerobic endurance, you should never become breathless to the point that you cannot talk while engaging in the activity.
Aerobic exercise involves activities that use the large muscle groups such as the legs and arms. Aerobic activities include: brisk walking, jogging, bicycling, swimming, aerobic dance, racket sports and rowing.
Muscular Strength
Muscular strength is the ability to exert a force against some type of resistance. Lifting a weight, picking up books from a desk and standing up from a chair are all examples of muscular strength. Strengthening the muscles allows people to lift a heavier weight, pick up more books from a desk or stand up from a chair with greater ease.
Muscular Endurance
Muscular endurance refers to the ability to repeat muscle exertions. Sit-ups, push-ups, moving many boxes of books and squatting repeatedly are examples of muscular endurance activities. As muscular endurance increases, the ability to repeat muscle exertions also increases.
Flexibility
Flexibility is the ability to move through the full range of motion allowed by a joint. Flexibility depends on many factors, including age, gender, body fat/muscle mass ratio and exercises done to enhance flexibility. Females tend to be more flexible than males, because of their body composition (body fat to muscle mass ratio). The older people get, the less flexible they become, because joint mobility decreases.
The more a joint is used, the more flexible it will become. Increasing flexibility is most effectively achieved through stretching. Stretching lengthens the muscles. The most important areas in which to maintain flexibility are the neck, shoulders, hamstring muscles (back of upper leg), chest and hips. It is important never to stretch a cold muscle. Always warm-up with some light activity before stretching. In addition, never bounce when stretching, and don't stretch to the point of pain.
Body Composition
Body composition refers to the percentage of body fat found in the body. The number of pounds one weighs is not as important as body fat percentage. The recommended body fat percentage range for women is 19-26 percent fat; for men, it's 15-19 percent fat. Women typically have a greater percentage of body fat due to the extra energy demands placed upon their bodies during pregnancy and breast-feeding-this is a natural occurrence.
Several different tests can be used to evaluate body fat percentage. Qualified health care professionals should perform these tests. Body fat percentage can be altered through a sound exercise program and healthful eating.
The F.I.T. Principle
The F.I.T. principle refers to guidelines for regular physical activity. F.I.T. stands for frequency, intensity and time.
Figuring Heart Rates
The target heart rate (THR) range is the recommended range to stay within while exercising aerobically. It is based on the maximum heart rate (MHR). These heart rates represent the number of times the heart beats per minute. THR is 60 to 85 percent of the MHR.
The MHR is calculated by subtracting your age from 220 (220 ' age = MHR). The maximum heart rate for a twelve-year-old is 208 beats per minute. The target heart rate range is found by multiplying the maximum heart rate by 60 percent and by 85 percent (MHR x .60 = bottom of THR; MHR x .85 = top of THR). The target heart rate range for a twelve year old is 125 to 177 beats per minute.
Finding the Heart Rate
Your heart rate is determined by counting your pulse. An easy way to figure the heart rate is to count the times the pulse beats in ten seconds and multiply by six to equal a minute. For example, if the pulse rate is 22 beats in ten seconds, the heart rate for one minute is 132. You can also count the number of beats in thirty seconds and multiply by two.
There are two recommended ways to find the pulse rate. The radial pulse is measured at the radial artery, which is located just below the base of the thumb on the inner side of the wrist. Find the pulse by placing the index finger and middle finger of the opposite hand on the radial artery.
The carotid pulse is located on the side of the neck just below the angle of the jawbone. This pulse is measure by placing the index and middle fingers on the carotid pulse.
Phases of a Workout
All exercise and physical activity sections should include three phases-warm-up, work out and cool down. The warm-up helps prepare the muscles for exercise and reduces injury. Five minutes of fast walking, slow jogging or push-ups and sit-ups followed by five minutes of stretching will adequately prepare the body for activity.
The work-out phase is the active section. It should include 20-60 minutes of aerobic activities. Aerobic activities are those that involve continuous, rhythmic motion using the large muscle groups.
The cool-down allows the body to adjust back to its resting state. The blood from the working muscles returns to the heart, the heart rate slows down, breathing returns to normal. Five to ten minutes of walking and gentle stretching is recommended to finish off a workout.
Two Elements of Fitness
Cardio-respiratory Fitness
Cardio-respiratory fitness pertains to the body's ability to utilize oxygen. Cardio-respiratory fitness allows people to last longer when participating in activities such as running, walking, climbing stairs, riding a bike or swimming. The more cardio-respiratory fitness people have, the easier it is for them to participate in activities. Cardio-respiratory fitness means blood is pumped through the heart and blood vessels with greater ease, thereby feeding the working muscles more fuel (oxygen) for work.
When exercising for aerobic endurance, people should never become breathless or work so hard that they cannot talk while engaging in the activity. Cardio-respiratory activities include those that use the large muscle groups such as the legs and arms:
Flexibility
Flexibility is the ability to move through the full range of motion allowed by a joint. Flexibility depends on many factors, such as age, gender, body fat/muscle mass ratio and exercises done to enhance flexibility. Females tend to be more flexible than males, because of their body composition (body fat to muscle mass ratio). The older people get, the less flexible they become, because joint mobility decreases. The more a joint is used, the more flexible it will become.
Increasing flexibility is most effectively achieved through stretching. Stretching lengthens the muscles. The most important areas in which to maintain flexibility are the neck, shoulders, hamstring muscles (back of upper leg), chest and hips. It is important to never stretch a cold muscle. Always warm up before stretching with some light activity. In addition, never bounce when stretching, and don't stretch to the point of pain.
Improving Fitness
Directions: Write a different title and list of activities on two pieces of poster board, as described in the following lists. Use colored markers for interest. Add pictures to enhance the posters (optional).
Improving Cardio-respiratory Fitness
Exercises That Improve Flexibility
Components of Physical Fitness
Physical fitness has five important components:
Aerobic Endurance/Cardio-respiratory Fitness
Aerobic endurance pertains to the body's ability to use oxygen. It is the combination of the respiratory system (lungs) and the circulatory system (cardio-heart and blood vessels) that provides the working muscles with enough oxygen to continue exercise for extended periods of time. Aerobic endurance allows you to last longer when participating in activities such as running, walking, climbing stairs, riding a bike or swimming. The more aerobic endurance people have, the easier it is for them to participate in physical activity.
When exercising for aerobic endurance, you should never be breathless or exercise to the point that you cannot talk while engaging in the activity. Aerobic exercising includes activities that use the large muscle groups such as the legs and arms. Aerobic activities include: brisk walking, jogging, bicycling, swimming, aerobic dance, racket sports and rowing.
Muscular Strength and Endurance
Muscular strength is the ability to exert a force against some type of resistance. Lifting a weight, picking up books from a desk and standing up from a chair are all examples of muscular strength. Strengthening the muscles allows people to lift heavier weights, pick up more books from a desk or stand up from a chair with greater ease.
Muscular endurance refers to the ability to repeat muscle exertions. Sit-ups, push-ups, moving many boxes of books and squatting repeatedly are examples of muscular endurance activities. As muscular endurance increases, the ability to repeat muscle exertions also increases.
Flexibility
Flexibility is the ability to move through the full range of motion allowed by a joint. Flexibility depends on many factors, including age, gender, body fat/muscle mass ratio and exercises done to enhance flexibility. Females tend to be more flexible than males because of their body composition (body fat to muscle mass ratio). The older people get, the less flexible they become, because joint mobility decreases. The more a joint is used, the more flexible it will become.
Increasing flexibility is most effectively achieved through stretching. Stretching lengthens the muscles. The most important areas in which to maintain flexibility are the neck, shoulders, hamstring muscles (back of upper leg), chest and hips. It is important to never stretch a cold muscle. Always warm up before stretching with some light activity. In addition, never bounce when stretching, and don't stretch to the point of pain.
Body Composition
Body composition refers to percentage of body fat found in the body. The number of pounds a person weighs is not as important as body fat percentage. Women should fall within the range of 19 to 26 percent body fat, and men should fall within the range of 15 to 19 percent body fat. Women typically have a greater percentage of body fat, due to the extra energy demands placed upon their bodies during pregnancy and breast feeding-this is a natural occurrence. Several different tests can evaluate body fat percentage. Qualified health care professionals should perform these tests. Body fat percentage can be altered through a sound exercise program and healthy eating habits (those that follow the dietary guidelines).
Fitness Guidelines
Recommended Activity Levels
All age groups benefit from physical activity. Current recommendations from the Centers for Disease Control and Prevention state that elementary school-aged children should accumulate at least 30 minutes of activity on all, or most, days of the week. Some of the activity should be in periods lasting 10 to 15 minutes or more and should include moderate to vigorous activity. Moderate activity is defined as activity that raises the heart rate to 50 to 75 percent of the maximum heart rate. Maximum heart rate is calculated using the following formula: 220 - your age x %. For example: If a 25-year-old adult would like to exercise at 50 percent of his or her maximum heart rate, the calculation would be 220 - 25 x .50 = 97.5 beats per minute. This would be considered the low end of the target heart rate zone. If this same adult would like to exercise at 75 percent of her or his maximum heart rate, the calculation would be 220 - 25 x .75 = 146 beats per minute. This would be considered the high end of the target heart rate zone.
