觉得这篇文章很有用，转过来 :)

If you're considering putting an exercise program together it's perfectly normal to
have a lot of questions swimming around in your head. What's the best activity to
participate in? How do I get the most out of exercising? How long should I exercise?

Often, the hardest part of getting into shape is taking the first step. Here are some
simple steps to help you begin your journey.

Think F.I.T.
To make physical improvements, you need to work your body harder than usual. This
is referred to as the overload principle. As your body becomes more conditioned, you
need to increase the frequency, intensity, or time of your workouts in order to
continue improving your fitness level.

Frequency: How often you exercise. For beginners, consider starting with 2-3 sessions
per week.
Intensity: How hard you exercise. For example, the pace you walk or run, the amount
of weight you lift, or your heart rate count.
Time: How long you perform an activity. "Time" can also refer to the number of sets
or repetitions you perform in weight training.

Aerobic exercise increases the health and function of your heart, lungs, and circulatory
system. For maximum effectiveness, aerobic exercise needs to be rhythmic,
continuous and involve the large muscle groups (primarily located in the lower part of
your body.) Walking, jogging, cycling, aerobic dance, and stair climbing are examples
of activities that use large muscle groups. Activities combining upper and lower body
movements such as cross-country skiing, rowing, and swimming can lead to even
higher levels of aerobic capacity.

Strength training is the process of exercising with progressively heavier resistance to
build or retain muscle. Unless you perform regular strength exercise, you will lose up to
one-half pound of muscle every year of life after age 25. Muscle is a very active tissue
with high energy requirements, even when you are asleep, your muscles are
responsible for over 25% of your calorie use. An increase in muscle tissue causes a
corresponding increase in the number of calories your body will burn, even at rest.

Flexibility is a critical element of an exercise program but it is often overlooked.
Stretching is important for a number of reasons; increases physical performance,
decreases risk of injury, increases blood supply and nutrients to the joints, increases
neuromuscular coordination, reduces soreness, improves balance, decreases risk of low
back pain, and reduces stress in muscles

The best exercise is an activity that you enjoy enough to really pursue enthusiastically.
Experiment with different forms of activity (cross training). Alternating new activities
with old favorites will keep your enthusiasm high. Cross training also helps avoid injury
due to repeatedly doing the same activity. Here are some suggestions:

Indoor (Facility) Activities: If the treadmill, stairmaster, rowing machine or stationery
cycle doesn't excite you, sample some group activities that strike your fancy.
Participate in a group cycling class, beat stress with yoga, find balance with martial
arts, stay cool with indoor swimming, or kick some you-know-what with boxaerobics.

At Home Activities: You don't need to join a gym to experience a variety of activities.
Your local video store or library will carry a variety of fitness videos that allow you to
workout in the privacy of your home. Some equipment may be required, depending
on the activity you select. A few inexpensive pieces of equipment include a jum
rope, a set of hand weights (preferably with weight plates that you can add and
remove), Dyna-Bands or tubing, or a basic step (for step aerobics).

If you enjoy working out at home then you may want to consider investing in a larger
piece of equipment such as a treadmill, ski machine, stationery bicycle, or elliptical
trainer.


Outdoor Activities: Outdoor activities abound during all four seasons. Sample the
variety of activities available to you. For example, take a hike to enjoy the Fall colors,
learn to cross-country ski when Old Man Winter visits, walk among the flowers in the
Spring, or dive into swimming during the hot months of Summer. Getting outdoors
into the fresh air not only adds variety to your exercise program but it seems to
provide an uplifting of one's spirit as well.

[此贴子已经被作者于2004-11-17 9:46:23编辑过]

To achieve cardiovascular benefits, the American College of Sports Medicine (ACSM)
recommends exercising 3-5 times per week (frequency) with a training heart rate of
60-85 percent of your maximum (intensity) for 20-60 minutes (time).

To attain muscular fitness benefits, the ACSM recommends weight training two days
per week (frequency), performing one to three sets of 10 repetitions (time) of eight
to ten different exercises at approximately 70-85 percent of your one repetition
maximum (intensity.)

If you're just beginning an exercise program, start in the low range of the above
recommendations. For example, participate in a cardiovascular activity (walking
aerobics, cycling, etc.) for 20 minutes, three times a week and add strength training
exercises to your workout, twice a week. Schedule your strength training workouts
with 48 hours rest in between to allow your muscles to recuperate and repair after
each workout.

Unfamiliarity with movements and equipment can prove frustrating enough that you may consider throwing in the towel. Take heart, it's normal to feel awkward in the beginning, especially if you have undertaken an activity that you aren't familiar with. It doesn't take long for your skill to improve if you stick with it. Afterall, even fitness instructors were once beginners!

If you attempt "too much, too soon" it will lead to soreness, fatigue and/or injuries. Work at your own level, start out slow, and gradually increase duration and level of difficulty as your body progresses. Getting fit is not an overnight proposition, it's a lifestyle commitment. Don't expect immediate dramatic changes in your body shape or weight loss. Although changes are happening internally, most external benefits won't become visible for the first four to six weeks. Stay focused on your lifestyle choice and celebrate the internal benefits you're experiencing such as increased energy, less stress and anxiety, higher self-esteem, and an increased feeling of well-being.

讲的挺全面的。这3相里，最不喜欢strength training。如果肌肉睡觉还燃烧热量，还是挺值得的。

以下是引用Chanel在2004-11-17 9:49:49的发言：
Unfamiliarity with movements and equipment can prove frustrating enough that you may consider throwing in the towel. Take heart, it's normal to feel awkward in the beginning, especially if you have undertaken an activity that you aren't familiar with. It doesn't take long for your skill to improve if you stick with it. Afterall, even fitness instructors were once beginners!

If you attempt "too much, too soon" it will lead to soreness, fatigue and/or injuries. Work at your own level, start out slow, and gradually increase duration and level of difficulty as your body progresses. Getting fit is not an overnight proposition, it's a lifestyle commitment. Don't expect immediate dramatic changes in your body shape or weight loss. Although changes are happening internally, most external benefits won't become visible for the first four to six weeks. Stay focused on your lifestyle choice and celebrate the internal benefits you're experiencing such as increased energy, less stress and anxiety, higher self-esteem, and an increased feeling of well-being.

it is so right, a "lifestyle commitment"...I guess here I can use "lifetime" too...
My problem is frequency. After the whole day working, I just could not get myself to gym. I enjoy working out at gym a lot. It's not boring to me at all even I run on treadmill for several months. The pity is I do not have enough time/energy to fulfill the commitment.

BTW, very good article, thanks Chanel mm...[em00]