“有氧运动”这个词汇这些年可谓是大行其道。

所谓有氧运动，指的是长时间进行运动（耐力运动），使得心（血液循环系统）、肺（呼吸系统）得到充分的有效刺激，提高心、肺功能。虽然一般来说慢跑、游泳、骑自行车、步行、原地跑、有氧健身操等都被视为有氧运动，但绝不等于你进行上述活动就真的能够起到有氧运动的效果——到底有没有效果，还是心跳说了算。一般来说，运动心跳若为最大心跳的60%-70%，只能算是基本瘦身运动；而传统认为较具健身效用的有氧运动，就要达到最大心跳的70-85%才可，而且最好持续20-60分钟。这也就意味着，有氧运动绝不是一件轻松的事情——难怪许多信誓旦旦尝试有氧运动者都以半途而废告终——更不要说像笔者这样从未有相关打算的懒人了。

幸好，懒人也有了懒人的福音。《哈佛健康》的一篇文章指出，即使是那些传统上连瘦身运动都算不上的基本适度运动，对身体健康依然有着极佳的作用。

这篇文章综述了大量报告，以下是主要数据：

  1. 每周步行9英里(14.49公里)，可以降低22%的死亡风险；
  2. 每周爬55层楼梯，可以降低33%死亡风险；
  3. 每周步行2.5个小时，可以降低30%的心血管疾病风险；
  4. 每周步行1小时，亦可降低51%的冠心病风险；
  5. 适度运动可以降低以下疾病的风险：中风21-34%，糖尿病16-50%，精神分裂15-50%，骨折40%，乳房癌20-30%，结肠癌30%-40%
  6. 有规律的进行每小时5.635公里的慢走，可以提高预期寿命3.7年

此文给出的健身方案很简单，每天花30-40分钟慢走2英里(3.22公里)，若为了瘦身则增量至4英里(6.44公里)。更重要的是，相比有氧运动强调持续性运动不同，这种适度活动的健身方案可以将总量分解成多次运动，每次只有8-12分钟也没有问题，对懒人而言无疑是更佳的选择。

有兴趣了解这篇文章详细内容的，可以看下面的原文引用：

Exercise — No Pain, Big Gains
Most men know that exercise is good for them. But if exercise means
a trip to the gym or a 5-mile run, exercise becomes a “spectator
sport” for too many men. Vigorous exercise is great for guys who
are so inclined, but for many others, there is a kinder, gentler way
to exercise for health.

The aerobics doctrine

The scientific study of exercise blossomed in the 1960s and 1970s. Researchers
used a tool called the maximum oxygen uptake test, which measures the
amount of oxygen sucked up by the lungs, pumped by the heart, and delivered
to the muscles during maximal exertion on a treadmill or stationary bicycle.
Improvements in the maximum oxygen uptake — also called the VO2max — quickly
became the gold standard for judging the benefits of exercise.
Research showed that the biggest improvements in the VO2max depend on
exercise that is intense enough to raise the heart rate to 70% to 85%
of its maximum heart rate for 20 to 60 minutes continuously, at least
three times a week. The aerobics doctrine was born along with the no
pain, no gain school of thought.

Aerobics – a hard sell

The aerobics doctrine gained acceptance just as Olympic champion Frank
Shorter and marathoner Bill Rodgers proved that Americans could run.
Running became the symbol of aerobic exercise and the marathon took over
as the icon of success. Despite extraordinary individual achievements,
however, the aerobics revolution did not succeed in getting our nation
off its collective duff.
The aerobics doctrine inspired the few but discouraged the many. A relatively
small number of lucky people discovered the benefits (and pleasures)
of aerobic exercise. But by proclaiming that the only way to really benefit
from exercise was through aerobic training, doctors discouraged people
who found aerobic activities, such as running, too difficult. According
to the “gospel of aerobics,” golf was the perfect way to ruin
a 4-mile walk. But we now know that’s wrong.

The benefits of moderation

New studies show that it’s possible to attain nearly all the health
benefits of exercise without high-intensity activity that leaves you
drenched in sweat. That means moderate exercise, such as walking, biking,
and gardening can help you get fit. Exercise intensity is less important
than the overall amount of time spent exercising, and intermittent exercise
is as effective as continuous activity. In fact, golf is beneficial,
as long as players walk the course and play two to three times a week.
Research involving more than 320,000 people from around the world proves
that regular moderate exercise can reduce risk factors, such as high
cholesterol, high blood sugar, blood pressure and body fat, which we
expect will improve health and reduce the risk for many chronic diseases.
Although we don’t have the advantage of randomized clinical trials that
evaluate the effects of exercise on cardiac events and mortality in healthy
men and women, doctors have data from 48 trials of patients with proven
coronary artery disease. About half of the 8,940 patients studied were
randomly assigned to receive the best medical and surgical care available,
while the others got the same standard of care and participated in a
cardiac rehabilitation program based on moderate exercise. The exercisers
came out on top. They enjoyed a 26% reduction in the risk of death from
heart disease and a 20% reduction in the overall death rate. It’s powerful
evidence that exercise protects the heart — and what’s good for
ailing hearts should be at least as beneficial for healthy ones!

Summary of the research

Group Activity Benefits
10,269 Harvard alumni ages 35-74 Walking at least 9 miles a week

Climbing at least 55 flights of stairs a week | 22% lower death rate

33% lower death rate
73,743 American women ages 50-79| Walking for at least 2.5 hours a week| 30% lower risk of cardiovascular

events
44,452 American male health professionals| Walking at least 30 minutes a day| 18% lower risk of coronary artery disease
39,372 American female health professionals| Walking at least 1 hour a week| 51% lower risk of coronary artery disease
72,488 American female nurses| Walking at least 3 hours a week| 35% lower risk of heart attack and cardiac death;
34% lower risk of stroke
30,640 Danish men and women ages 20-93| Spending 2-4 hours a week on light leisure-time activity| 32% lower mortality rate

If reducing risk factors for cardiovascular disease were the only benefit
of moderate exercise, it would still be vitally important. But moderate
exercise also helps:

  • Promote weight loss – Exercise, along with diet, is essential
    for losing weight.

  • Decrease the risk for stroke (by 21%-34%), diabetes (by 16%-50%),
    dementia (by 15%-50%), fractures (by 40%), breast cancer (by 20%-30%),
    and colon cancer (by 30%-40%).

  • Slow the physiologic changes associated with aging.

  • Increase life expectancy – A 2005 analysis of data from the
    famed Framingham Heart Study reports that people who exercise regularly
    live an additional 3.7 years, compared with sedentary individuals.
    Walking at a 17-minutes-per-mile pace (about 3.5 miles an hour) was
    sufficient to produce this extraordinary gain. Another 2005 study showed
    that moderate exercise (walking 8.6 miles a week at 40% to 55% of maximum)
    will increase the VO2max, though not to the same degree as aerobic
    training.

We know what you’re thinking: There must be some catch. There isn’t.
To get the astounding health benefits of exercise merely takes walking
at a moderate pace for 30 to 40 minutes a day, with the goal of covering
about 2 miles. If you need to lose weight, build up to 4 miles a day.
Remember you can divide your walking into 8- to 12-minute segments throughout
the day if that’s more convenient. And you can substitute other activities,
such as climbing stairs, gardening, biking, dancing, swimming, playing
racquet sports, or yes, even golfing — as long as you walk the
course.

The bottom line

Moderate exercise is the key to exercising for health. But many people
will get extra benefits by adding exercises for strength, flexibility,
and balance — not necessarily at a gym under the watchful eye of
a trainer, but at home in just a few minutes a day. And a prudent diet
is an essential part of a healthy lifestyle to prevent many of the chronic
illnesses that plague modern societies. Medical science continues to
make astounding advances. It has taken the collective effort of many
dedicated scientists to bring us back to the wisdom of Hippocrates. Some
2,400 years ago, the Father of Medicine said, “If we could give
every individual the right amount of nourishment and exercise, not too
little and not too much, we would have found the safest way to health.”