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The ultimate focus of the health-related components of physical fitness is to provide a framework for components that are necessary for good health. There are five areas of health-related fitness: cardiorespiratory endurance, muscular strength, muscular endurance, flexibility, and body composition.
Cardiorespiratory endurance is the ability to carry out prolonged, large muscle, dynamic movements at a moderate to high level of intensity. In cardiorespiratory endurance, the heart, lungs, and blood vessels work together in three main ways: delivering oxygen to body tissues, delivering nutrients, and removing waste products. Cardiovascular activity makes the heart beat more rapidly to meet the demands of the movement. Both planned exercise and physical activity throughout the day can count toward meeting the Physical Activity Guidelines. For example, physically active occupations can count toward meeting the guidelines, as well as active transportation choices (walking or bicycling). All types of cardiovascular activities can count as long as they are of sufficient intensity and duration. Over time, regular cardiovascular activity makes the cardiovascular system more fit.
| Examples of Different Aerobic Physical Activities and Intensities | |
|---|---|
| Moderate Intensity | Vigorous Intensity |
| Walking briskly | Racewalking, jogging, or running; hiking uphill or with a heavy pack |
| Water aerobics | Swimming laps |
| Bicycling at less than 10 miles (6.2 km) per hour | Bicycling at more than 10 miles (6.2 km) per hour |
| Tennis (doubles) | Tennis (singles) |
| Ballroom dancing | Jumping rope |
| General gardening | Heavy gardening, such as continuous digging or shoveling |
Muscular strength is the ability of the muscles to exert force over a single or maximal effort. Improving muscular strength involves making the muscles do more work than they are accustomed to doing. That is, they overload the muscles. Resistance training, including weight training, is a familiar example of muscle-strengthening activity. Other examples include working with resistance bands, doing calisthenics that use body weight for resistance (such as push-ups, pull-ups, and sit-ups), carrying heavy loads, and heavy gardening (such as digging or hoeing).
Muscle-strengthening activities provide additional benefits not found with aerobic activity. The benefits of muscle-strengthening activity include increased bone strength and muscular fitness. Muscle-strengthening activities can also help maintain muscle mass during a program of weight loss.
Muscle-strengthening activities count if they involve a moderate to high level of intensity or effort and work the major muscle groups of the body: the legs, hips, back, chest, abdomen, shoulders, and arms. Muscle-strengthening activities for all the major muscle groups should be done at least 2 days a week.
Muscle-strengthening exercises should be performed to the point at which it would be difficult to do another repetition without help. When resistance training is used to enhance muscle strength, one set of 8 to 12 repetitions of each exercise is effective, although two or three sets may be more effective. Development of muscle strength and endurance is progressive over time. Increases in the amount of weight or the days a week of exercising will result in stronger muscles.
Muscular endurance is the ability to exert a force over a period of time or repetitions. You’ll learn more about resistance training principles in a future lesson, but the same types of equipment in the form of external resistance can be used for both muscular strength and muscular endurance. A person might use weights to increase the amount they can lift over time (muscular strength) or else use weights in a circuit-training type format to see how many repetitions they can get in a given time period (muscular endurance). Activities that build muscular endurance can also overlap with activities that build cardiorespiratory endurance, such as swimming, dancing, and circuit training.
Flexibility is the ability to move your joints through a full range of motion. Examples of activities where flexibility is used are yoga, stretching, and tai chi. Some types of activity, such as dance or gymnastics, require more flexibility than others. Stretching exercises can increase flexibility when done consistently over time.
Flexibility activities are an appropriate part of a physical activity program since they help people maintain pain-free range of motion. However, the research on flexibility activities is not clear on specific health benefits or injury reduction. In addition, time spent doing flexibility activities by themselves does not count toward meeting the aerobic or muscle-strengthening Guidelines.
As you’ve learned, body composition refers to the proportion of fat mass and fat-free mass within the body. Body composition is a unique component of health-related fitness because it is not an action we do (unlike cardiovascular endurance activities, muscular strength and endurance activities, and flexibility activities). Instead, it is an outcome of other healthy behaviors, where changes in body composition usually occur as a result of other health-related fitness components, as well as changing eating habits. Body composition is included as part of the five health-related fitness components because a balanced amount of fat and muscle is vital for health and wellness.
The first step in achieving or maintaining a healthy body composition is to meet the minimum level of physical activity in the Guidelines. People who are at a healthy body weight but slowly gaining weight can either gradually increase the level of physical activity (toward the equivalent of 300 minutes a week of moderate-intensity aerobic activity), or reduce caloric intake, or both, until their weight is stable. By regularly checking body weight, people can find the amount of physical activity that works for them.
Many adults will need to do more than the recommended 150 minutes a week of moderate-intensity aerobic physical activity as part of a program to lose weight or keep it off. These adults should do more physical activity and/or further reduce their caloric intake. Some people will need to do the equivalent of 300 or more minutes of moderate-intensity physical activity a week to meet their weight-control goals. Combined with restricting caloric intake, these adults should gradually increase minutes or the intensity of aerobic physical activity per week, to the point at which the physical activity is effective in achieving a healthy weight.
It is important to remember that all activities, both baseline and physical activity, “count” for energy balance. Active choices, such as taking the stairs rather than the elevator or adding short episodes of walking to the day, are examples of activities that can be helpful in weight control and improving body composition.
Using the FITT principle is a way to apply the Physical Activity Guidelines and implement improvements in your own health-related physical fitness. FITT stands for:
| Cardiorespiratory | Muscular Strength | Muscular Endurance | Flexibility | |
|---|---|---|---|---|
| Frequency | 3–5 times per week or more, at least 3 days a week | 2 or more days per week using all major muscle groups | Daily for some muscle groups; perform 3–4 times per week | No specific recommended frequency; useful to include with warm-up and cool-down for other activities |
| Intensity | In moderate intensity, a person can talk, but not sing, during the activity. In vigorous intensity, it is difficult to say more than a few words without pausing for breath | Perform movements at 60–80% of the maximal amount you can lift (1 rep max) | Start with bodyweight, then add resistance, performing movements at less than 50% of the maximal amount you can lift (1 rep max). | Stretch all major muscle groups and associated joint areas, hold to the point of mild tension |
| Time | 20–60 minutes of continuous activity | 15–60 minutes, 1–3 sets of 8–12 reps | 30–60 minutes, 1–3 sets of 15 or more reps | Hold stretches for 15–30 seconds, perform 1–3 repetitions of each stretch |
| Type | Choose rhythmic activities that use large muscle groups, such as walking, cycling, swimming, or dancing | Done through resistance such as body weight, bands, weighted implements like free weights, machines, and others | Done through resistance such as body weight, bands, weighted implements like free weights, machines, and others | Can be improved through static stretches, controlled dynamic stretches, or other activities involving flexibility, such as yoga |
Each component of the FITT principle can be used to guide you in starting a regular physical activity or progressing to improve your fitness. Inactive adults should work gradually toward reaching the Physical Activity Guidelines. The initial amount of activity should be at a light or moderate intensity, for short periods of time, with the sessions spread throughout the week. Even 60 minutes a week of moderate-intensity physical activity can provide some health benefits.
Gradual progression is important to reduce the risk of injury and reduce fatigue. In addition, a general rule of thumb is to change only one component of FITT at a time as you progress. An inactive person might try to gradually be active more frequently before increasing time or intensity. Or, muscle-strengthening activities might be done just one day a week starting a light or moderate level of effort. Over time, the number of days a week can be increased to 2, and then possibly to more than 2. After that, the level of effort (intensity) can be increased slightly each week until it becomes moderate to high.
IN CONTEXT
Adults can meet the Physical Activity Guidelines in all sorts of ways and with many types of physical activity through applying FITT. The choices of types and amounts of physical activity depend on personal health and fitness goals. Here is one example:
Douglas is an active middle-aged man who was actively playing soccer when he was younger. His goal is to get back into shape by running regularly. In addition to his job operating heavy equipment, he walks 30 to 40 minutes a day on 5 days each week. He also lifts weights 2 days a week.
Starting out: Douglas starts a walk/jog program with a coworker and plans to gradually replace walking with jogging and then running. The first week he goes out on 5 days, walking for 25 minutes and jogging for 5 minutes.
Making good progress: Each week, Douglas gradually increases the time spent jogging (vigorous-intensity activity) and reduces the time spent walking (moderate intensity activity). He also continues his weight-lifting program.
Reaching his goal: Eventually, Douglas is running 30 to 45 minutes 4 days a week and lifting weights 2 days a week. He goes for a 1-hour bicycle ride on most weekends.
Because Douglas was already active most days of the week, and because he wanted to progress from walking to running, modifying Intensity in FITT made the most sense for his goals.
Source: THIS TUTORIAL HAS BEEN ADAPTED FROM (1) "WELLNESS" BY EXTENDED LEARNING INSTITUTE (ELI)" AT NOVA. ACCESS FOR FREE AT: oer commons. (2) "HEALTH EDUCATION" BY COLLEGE OF THE CANYONS. ACCESS FOR FREE AT: open.umn.edu. LICENSING (1 & 2): CREATIVE COMMONS ATTRIBUTION 4.0 INTERNATIONAL.
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