你需要锻炼多少才合适?

How much exercise do you need to improve and maintain health? What kind of exercise do you need? Is walking enough, or do you need to jog? What about strength training? The American College of Sports Medicine and the American Heart Association updated their Physical Activity Guidelines in August, 2007. These guidelines are for healthy adults aged 18-65. There are additional guidelines for those over age 65.
你需要多少量的锻炼改善和保持健康？你需要哪种锻炼？步行可以吗，还是你需要跑步？力量训练呢？美国运动医学学院和美国心脏协会在2007年8月更新了他们的体育运动健身指南。这些指南针对年龄18-65岁的健康成年人。对于超过65岁的有另外补充的指南。

Choose Moderate or Vigorous Aerobic (Endurance) Exercise
选择中度的或者剧烈的有氧（耐力）锻炼

All healthy adults need endurance exercise, which noticeably accelerates their heart rate for at least 10 minutes at a time. They can get it either with moderate or vigorous exercise -- you can enjoy a brisk walk, jog, dance, bike, or swim. You can also mix it up and enjoy moderate some days and vigorous other days, if you wish.
所有的健康成年人需要耐力锻炼，一次至少在10分钟显著地加速心跳。他们可以从中度的或者剧烈的锻炼中得到这样的效果--你可以快步走，慢跑，跳舞，单车，或者游泳。你还可以混合使用，几天享受中度的锻炼和几天剧烈的锻炼，如果你想的话。

Moderate Aerobic Exercise for 30 Minutes a Day, 5 Days a Week
中度的有氧锻炼，一周5天，每天30分钟

   * How Long: A minimum of 30 minutes a day. The 30 minutes can be broken up into 10 minute increments.
* 多长：每天至少30分钟。这30分钟可以被分成10分钟的增量。

   * How Often: At least 5 days a week.
* 多久一次：每周至少5天

    * What Does Moderate Feel Like? A moderate level of activity noticeably increases your heart rate and breathing rate. You may sweat, but you are still able to carry on a conversation.
* 中度锻炼的感觉像什么？中度锻炼显著地提高你的心率和呼吸率。你也许会流汗，但是你还是能够同时在进行交谈。

    * Kinds of Exercise: Brisk walking, easy jogging, treadmilling, elliptical trainer, bike riding, swimming, dancing.
* 锻炼的种类：快步走，慢跑，椭圆机，跑步机，骑单车，游泳，跳舞
  
    * What Doesn't Count: An easy walk of under 10 minutes doesn't count as aerobic activity. You can build moderate activity into your lifestyle by walking briskly for at least 10 minutes to the bus, etc. But just adding steps on your pedometer doesn't count.
* 哪种不算：少于10分钟的舒服的步行不能算作有氧运动。你可以把中度的锻炼移入你的生活方式中，比如至少慢跑10分钟去公车等等。但是仅仅在你计步器上增加步数是不算的。

    * How to Start Walking
* 怎样开始步行

    * Weekly Walking Workout Schedule: Vary your walking intensity.
* 每周步行锻炼计划表：变化步行强度

Or - Vigorous Aerobic Activity for 20 Minutes on 3 Days Each Week
或者-每周3天，每天20分钟剧烈的有氧运动

   * How Long: 20 minutes.
多长：20分钟

    * How Often: At least 3 days a week.
* 多久一次：每周至少3天

    * What Does Vigorous Aerobic Exercise Feel Like? You are breathing rapidly and only able to speak in short phrases. Your heart rate is substantially increased and you are likely to be sweating.
* 剧烈的有氧锻炼感觉象什么？你呼吸地很快，只能够讲简短的词组。你的心率很大程度上加速了，你很有可能流汗。

    * Kinds of Vigorous Aerobic Exercise: Running, cycling, or swimming at an intense level.
* 剧烈的有氧锻炼的种类：跑步，骑自行车，或者以一定的强度游泳。

Add Strength Training Two Days a Week
增加每周2天的力量训练

Moderate or vigorous aerobic activity is needed, but you also need strength training exercise two days a week.
中度或者剧烈的有氧运动是必须的，但是你还是需要每周2天的力量训练。

   * How Many: Do eight to 10 strength-training exercises, eight to 12 repetitions of each exercise.
* 多少：做8-10种力量训练运动，每种运动做8-12次重复。

    * How Often: Two days each week.
* 多久一次：每周2天

    * What Are Strength Training Exercises? Strength training exercises have you lift, push or pull to increase muscle strength and endurance. These include lifts with dumbbells and barbells. You may also use resistance bands or gym equipment.
* 力量训练运动是什么？力量训练运动举，推或者拉提高肌肉力量和耐力。这些包括举哑铃和杠铃。你也可以使用拉伸带或者健身器材。

    * Strength Training Guide
* 力量训练指南

More Is Better
更多更好

These guidelines are the minimum for maintaining good health. If you workout for longer or more often, you further improve your fitness and reduce your risk of chronic disease and weight gain.
这些指南是维持好的健康的最低标准。如果你锻炼的时间更长或者更久，你会进一步改善你的健康，减少你得慢性病和变胖的危险。

Changes in Guidelines Since 1995
自从1995版指南中的改变

The last set of guidelines was issued in 1995. The 2007 guidelines made several changes.
上一版的指南是在1995年出版。2007版指南做了一些改变。

   * Strength training is added.
 * 添加了力量训练

    * The number of days per week are now spelled out.
* 现在阐明了每周的训练天数

    * Vigorous physical activity guidelines are spelled out.
* 阐明了有氧运动指南

    * It is made clear that you could mix and match moderate and vigorous activities.
* 这很清晰地说明了你可以混合搭配中度和剧烈的运动。

    * Aerobic activity doesn't include easy walking, doing chores, etc. for less than 10 minutes at a time.
* 有氧运动不包括舒服的散步，做家务，等等一次少于10分钟的。

    * "More is better" is spelled out.
* 阐明了“更多更好”

    * Short bouts of exercise of at least 10 minutes can be added up to the total time needed.
* 至少10分钟的短时间阶段运动可以加到需要的全部时间里。

Exercise Guidelines for Those Over Age 65: Guess what, you need even more kinds of exercise as you age.
针对年龄超过65岁的锻炼指南：你们猜怎么着，在你们的年龄你们甚至需要更多种类的运动。