Glossary of Terms
Defining Fitness
What does it mean to be physically "fit?" Physical fitness is defined as "a set of attributes that people have or achieve that relates to the ability to perform physical activity" (USDHHS, 1996). In other words, it is more than being able to run a long distance or lift a lot of weight at the gym. Being fit is not defined only by what kind of activity you do, how long you do it, or at what level of intensity. While these are important measures of fitness, they only address single areas. Overall fitness is made up of five main components. In order to assess your level of fitness, look at all five components together:
Cardiorespiratory Endurance (Cardiorespiratory
Fitness)
Cardiorespiratory endurance is the ability of the body's circulatory and
respiratory systems to supply fuel during sustained physical activity (USDHHS,
1996 as adapted from Corbin & Lindsey, 1994). To improve your
cardiorespiratory endurance, try activities that keep your heart rate
elevated at a safe level for a sustained length of time such as walking,
swimming, or bicycling. The activity you choose does not have to be
strenuous to improve your cardiorespiratory endurance. Start slowly with an
activity you enjoy, and gradually work up to a more intense pace.
Muscular Strength
Muscular strength is the ability of the muscle to exert force during an
activity (USDHHS, 1996 as adapted from Wilmore & Costill, 1994). The key to
making your muscles stronger is working them against resistance, whether
that be from weights or gravity. If you want to gain muscle strength, try
exercises such as lifting weights or rapidly taking the stairs.
Muscular Endurance
Muscular endurance is the ability of the muscle to continue to perform
without fatigue (USDHHS, 1996 as adapted from Wilmore & Costill, 1994).
To improve your muscle endurance, try cardiorespiratory activities such as
walking, jogging, bicycling, or dancing.
Body Composition
Body composition refers to the relative amount of muscle, fat, bone, and
other vital parts of the body (USDHHS, 1996 as adapted from Corbin and
Lindsey, 1994). A person's total body weight (what you see on the bathroom
scale) may not change over time. But the bathroom scale does not assess how
much of that body weight is fat and how much is lean mass (muscle, bone,
tendons, and ligaments). Body composition is important to consider for
health and managing your weight!
Flexibility
Flexibility is the range of motion around a joint (USDHHS, 1996 as
adapted from Wilmore & Costill, 1994). Good flexibility in the joints
can help prevent injuries through all stages of life. If you want to
improve your flexibility, try activities that lengthen the muscles such as
swimming or a basic stretching program.
Other Terms
Calorie, Kilocalorie
A measure of energy from food. (3,500 kilocalories of food energy = 1 pound
of body weight). Also the amount of heat required to raise the temperature
of 1 gram of water 1° C (1000 calories = 1 kilocalorie). An interesting
fact: When we see "Calories" on a food label it is actually measuring
kilocalories (kcal).
Cardiorespiratory fitness (also called aerobic endurance or
aerobic fitness)
Cardiorespiratory endurance is the ability of the body's circulatory and
respiratory systems to supply fuel and oxygen during sustained physical
activity.
Fitness
Physical fitness is defined as "a set of attributes that people have or
achieve that relates to the ability to perform physical activity." (USDHHS,
1996) See above for more.
Exercise
Exercise is physical activity that is planned or structured. It involves
repetitive bodily movement done to improve or maintain one or more of the
components of physical fitness—cardiorespiratory endurance (aerobic
fitness), muscular strength, muscular endurance, flexibility, and body
composition.
Household physical activity
Household physical activity includes (but is not limited to) activities
such as sweeping floors, scrubbing, washing windows, and raking the lawn.
Inactivity
Inactivity is not engaging in any regular pattern of physical activity
beyond daily functioning.
Kilocalorie
The amount of heat required to raise the temperature of 1 kg of water 1° C.
Kilocalorie is the ordinary calorie discussed in food or exercise
energy-expenditure tables and food labels.
Leisure-time physical activity
Leisure-time physical activity is exercise, sports, recreation, or hobbies
that are not associated with activities as part of one's regular job
duties, household, or transportation.
- Walking slowly
- Golf, powered cart
- Swimming, slow treading
- Gardening or pruning
- Bicycling, very light effort
- Dusting or vacuuming
- Conditioning exercise, light stretching or warm up
MET
The standard metabolic equivalent, or MET, level. This unit is used to
estimate the amount of oxygen used by the body during physical activity.
1 MET = the energy (oxygen) used by the body as you sit quietly,
perhaps while talking on the phone or reading a book.
The harder your body works during the activity, the higher the MET.
- Any activity that burns 3 to 6 METs is considered moderate-intensity physical activity.
- Any activity that burns > 6 METs is considered vigorous-intensity physical activity.
Moderate-intensity physical activity
Moderate-intensity physical activity refers to a level of effort in which a
person should experience:
- Some increase in breathing or heart rate
- a "perceived exertion" of 11 to 14 on the
Borg scale
- the effort a healthy individual might expend while walking briskly, mowing the lawn, dancing, swimming, or bicycling on level terrain, for example.
- 3 to 6 metabolic equivalents (METs); or
- any activity that burns 3.5 to 7 Calories per minute (kcal/min)
- Walking briskly
- Golf, pulling or carrying clubs
- Swimming, recreational
- Mowing lawn, power motor
- Tennis, doubles
- Bicycling 5 to 9 mph, level terrain, or with a few hills
- Scrubbing floors or washing windows
- Weight lifting, Nautilus machines or free weights
Occupational physical activity
Occupational physical activity is completed regularly as part of one's job.
It includes activities such as walking, hauling, lifting, pushing,
carpentry, shoveling, and packing boxes.
Physical activity
Physical activity is any bodily movement produced by skeletal muscles that
result in an expenditure of energy.
Physical fitness
Physical fitness is a set of attributes a person has in regards to a
person's ability to perform physical activities that require aerobic
fitness, endurance, strength, or flexibility and is determined by a
combination of regular activity and genetically inherited ability.
Regular physical activity
A pattern of physical activity is regular if activities are performed:
- most days of the week, preferably daily;
- 5 or more days of the week if moderate-intensity activities (in bouts of at least 10 minutes for a total of at least 30 minutes per day); or
- 3 or more days of the week if vigorous-intensity activities (for at least 20-60 minutes per session).
Note: These are minimum recommendations, greater health outcomes can be achieved by doing additional types activities and/or increasing time spent doing activities.
Transportation physical activity
Transportation physical activity is walking, biking or wheeling (for
wheelchair users), or similar activities to and from places such as: work,
school, place of worship, and stores.
Vigorous-intensity physical activity
Vigorous-intensity physical activity may be intense enough to represent a
substantial challenge to an individual and refers to a level of effort in
which a person should experience:
- large increase in breathing or heart rate (conversation is difficult or “broken”)
- a "perceived exertion" of 15 or greater on the
Borg
scale;
- the effort a healthy individual might expend while jogging, mowing the lawn with a nonmotorized pushmower, participating in high-impact aerobic dancing, swimming continuous laps, or bicycling uphill, carrying more than 25 lbs up a flight of stairs, standing or walking with more than 50 lbs for example.
- greater than 6 metabolic equivalents (METs); or
- any activity that burns more than 7 kcal/ min
- Racewalking, jogging or running
- Swimming laps
- Mowing lawn, hand mower
- Tennis, singles
- Bicycling more than 10 mph, or on steep uphill terrain
- Moving or pushing furniture
- Circuit training
Weight-bearing physical activity
Any physical activity that imparts a load or impact (such as jumping or
skipping) on the skeleton.
References
U.S. Department of Health and Human Services. Physical activity and health: a report of the Surgeon General. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion; 1996.
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Page last updated: March 26, 2008
Content Source: Division of Nutrition, Physical Activity and Obesity, National Center for Chronic Disease Prevention and Health Promotion
