P–R

physical activity recommendations The guide-
lines health and fitness experts suggest as mini-
mum standards to maintain a FITNESS LEVELthat
supports good health and reduces HEALTH RISK FAC-
TORSfor conditions such as CARDIOVASCULAR DISEASE
(CVD), type 2 DIABETES, OSTEOPOROSIS, OSTEOARTHRI-
TIS, and OBESITY. General physical activity recom-
mendations emphasize AEROBIC EXERCISE to
improve AEROBIC CAPACITYbecause this is the foun-
dation for physical fitness.
The amount of physical activity necessary to
have a positive effect on health is less than people
commonly perceive. Recent research findings
demonstrate that when it comes to exercise, a lit-
tle goes a long way. Though more is nearly always
better, the baseline recommendations for physical
activity to support health are modest. To achieve
and maintain a moderate fitness level health
experts recommend healthy adults engage in

• 30 minutes of moderately intense physical
  activity on five days of each week
  and


• 20 minutes of vigorous physical activity on
  three days of each week

WARMUPand stretching should open and close
every activity session, improving FLEXIBILITY and
lowering the risk for injury. Walking is an ideal
activity for exercise of moderate intensity and has
the added advantage of being easy for most people
to incorporate into their daily lifestyle routines.
Walking is also a good RESISTANCE EXERCISE, improv-
ing BONE DENSITY. Short sessions, such as 5 to 10
minutes at a time, that add up to 30 minutes over
the course of a day are as effective as a single, con-
tinuous 30-minute sessions.

Vigorous physical activities are those which

raise HEART RATEto 60 percent of maximum for 20

minutes or longer and consume 7 calories or more

(eight metabolic equivalents [METs]) per minute.

Running, bicycling, swimming, cross-country ski-

ing, jumping rope, step aerobics, aerobic dance,

rowing, and stair stepping are among the numer-

ous activities capable of accomplishing this objec-

tive. Vigorous physical exercise is most effective

when it continues for 20 minutes or longer. Most

vigorous exercise also incorporates resistance,

increasing MUSCLE STRENGTH and mass as well as

supporting BONEdensity.

Meeting these recommendations increases

energy expenditure by 1,200 to 1,400 calories

each week, helping with WEIGHT LOSS AND WEIGHT

MANAGEMENT. For a person striving to lose weight,

exercising at the recommended level can allow

weight loss of 18 to 21 pounds over the course of

a year without a change in the number of calories

consumed. Exercise in combination with nutri-

tious EATING HABITSthat maintain dietary intake at

the recommended level further expedites weight

loss. Adding physical activity beyond these recom-

mendations, which health experts encourage, fur-

ther improves physical fitness and aerobic capacity

and lowers health risk factors for HYPERTENSION

(high BLOOD PRESSURE), HYPERLIPIDEMIA, ATHEROSCLE-

ROSIS, CORONARY ARTERY DISEASE(CAD), and INSULIN

RESISTANCE.

Health experts recommend a minimum of 60

minutes of moderate physical activity daily (seven

days a week) for children and adolescents.

Research findings support the belief that such a

level of physical activity provides health benefits

that extend well into adulthood. Among these

benefits are strong bones, cardiovascular effi-

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