Encyclopedia of Health and Medicine

214 Fitness: Exercise and Health
hard. A person who can carry on an extended
conversation or sing during exercise is likely
below his or her target heart rate and is not working
hard enough for aerobic conditioning.
CALCULATING TARGET HEART RATE
The standard formula for calculating target HEART
RATE is 220 minus one’s age (an estimated maximum
heart rate), then multiplying the result by
60 percent. For example, the target heart rate for
a person 35 years old is 111 beats per minute:
220 – 35 = 185 x 0.6 = 111.
Aerobic exercise uses the large MUSCLE groups
in rhythmic, repetitive activity that increases the
body’s consumption of oxygen, and is the core of
cardiovascular CONDITIONING. Regular aerobic exercise
improves the all-around efficiency of the cardiovascular
system including
• more powerful contractions of the HEART to
pump BLOOD out to the body
• the ability of the LUNGS to exchange carbon
dioxide for oxygen
• the ability of the muscles in the body to contract
with power and force
• the ability of the blood vessels to dilate (open)
to carry more blood with each beat of the heart
• lower BLOOD PRESSURE as a result of reduced
resistance to the flow of blood
Health experts recommend a minimum of 30
minutes of aerobic exercise three days every week
and encourage more. At the onset of an aerobic
exercise program a person is likely to achieve target
heart rate quickly because the heart is not
accustomed to working in such a way. It is important
to stay at the target heart rate for as long as
possible, which may not be a full 20 minutes at
first. As the FITNESS LEVEL and AEROBIC CAPACITY
improve, it takes longer to reach and becomes easier
to maintain one’s target heart rate.
People who want to increase their fitness levels
should increase both the length and frequency of
their exercise sessions, for example 45 minutes of
aerobic activities five days a week. The higher a
person’s aerobic capacity, the more effort the person
must exert to achieve and maintain his or her
target heart rate. Competitive athletes and people
at high aerobic capacity may derive greater benefit
from exercising at a target heart rate that is 70 to
80 percent of maximum heart rate.
Among the most familiar and popular aerobic
activities are running, swimming, cross-country
skiing, and bicycling. Brisk walking (five miles per
hour) is aerobic as well. Sports such as basketball,
volleyball, soccer, and singles tennis also provide
an aerobic workout. Participating in aerobic exercise
at less than an aerobic level (below target
heart rate) provides numerous health and fitness
benefits, too, as part of maintaining a physically
active lifestyle.
AEROBIC ACTIVITIES
basketball
bicycling
climbing stairs
cross-country running
cross-country skiing
dancing
handball
ice skating
inline skating
jogging
jumping rope
racquetball
roller skating
rowing
running
snow shoeing
soccer
spinning
stair-stepping
stationary cycling
swimming
tennis (singles)
volleyball
walking
See also CARDIAC CAPACITY; EXERCISE AND HEALTH;
FLEXIBILITY; LIFESTYLE AND HEALTH; OBESITY AND HEALTH;
RESISTANCE EXERCISE; STRENGTH; WEIGHT LOSS AND
WEIGHT MANAGEMENT.
aging, changes in physical ability and fitness
needs that occur with As a person grows older,
his or her physical capabilities, STRENGTH, FLEXIBILITY,
AEROBIC CAPACITY, exercise needs, metabolic rate,
body composition, and risk for injury change.
Children and Exercise
Children require physical activity for proper development
and growth. BONE and MUSCLE development
relies in part on the stimulation from
resistance activities such as walking and running.
Preschool-age children tend to be on the go constantly.
However, many develop fairly sedentary
habits by the time they reach school age, with
activities such as watching television, using the