你发誓今年要跑一次马拉松。

好消息来了：不必为没开始练习马拉松而产生负罪感了。

其实不用跑到5英里（约8千米）就能获得像长跑等耐力训练同样的效果。

没错，每天快跑5到10分钟就能延年益寿，跟跑几小时是一样的。实际上，与每周跑步超过3小时一样，每周跑步不足一小时（每天跑几分钟）可在心脏健康方面达到同等的好处。

此发现与近期研究结果一致：长时间耐力运动所能获得的某些健康益处，通过短时间爆发性的剧烈运动同样可以获得。

马拉松与间歇运动

最流行同时也是研究最多的一种快速锻炼法是间歇训练。简单说，就是尽全力锻炼，然后休息，再尽全力锻炼。

最佳锻炼时长？5-10分钟是比较典型的（甚至有一款纽约时报的APP建立在此基础上，叫7分钟锻炼法）。

根据过去10年的研究，尽管间歇锻炼法锻炼时长比马拉松训练短得多，但从从长远看，间歇锻炼更健康。2012年的一项研究对比了传统持续性跑和间歇跑，结论是两组跑步者的锻炼效果几乎一致。仅有一个小的区别：间歇跑步者摄氧量的峰值更佳，这是衡量耐力的一个重要指标。

另一个发表在糖尿病杂志《Diabetologia》的研究发现，快走3分钟然后休息3分钟对于血糖的控制远比匀速持续走要好。

还是不相信？

你要考虑的是，长跑可能对你不利。

一些证据表明，像马拉松赛前数周数月的准备以及马拉松本身这样的长时间的剧烈运动会产生免疫功能降低、消化不良等副作用。

有研究表明，运动达到身体极限，会降低上呼吸道抵抗感冒及流感的能力。而短时间运动可以加强免疫力，降低患病风险，即使生了病还能减轻病痛。

71%的长跑者会伴有腹部绞痛、腹泻（腹泻很常见，被跑步者称为运动性腹泻或跑步性腹泻）。很多跑步者甚至是长期坚持跑步的人在长跑中或者刚跑完会感到胃酸反流，对身体的不利影响跟胃灼热、消化不良、咳嗽、声音嘶哑、气喘差不多。

归根到底，无论坚持长跑还是选择每天间歇性快跑，运动量并非越大越好。

原文来自Business Insider

Here's what you should be doing to get fit instead of training for a marathon

So you swore you'd run a marathon this year.

Good news: You can stop feeling guilty about not starting to train for it yet.

As it turns out, you can get some of the same benefits of long-distance running and other types of endurance training without ever passing the five-mile mark.

That's right. Running fast and hard for five to 10 minutes a day can add years to your life, just as running for hours can. In fact, people who run for less than an hour a week — so long as they get in their few minutes of daily running — getsimilar benefits in terms of heart healthcompared with people who run more than three hours a week.

That finding squares with recent research showing thatshort bursts of intense exercise can provide some of the same health benefitsas long, endurance-style workouts.

Marathoners, meet interval training

One of the most popular forms of the quick workout — and the one that has been studied the most — isinterval training. Basically, you work yourself as hard and fast as you can for a few minutes, rest, then do it again.

The best part? It typically lasts between five and 10 minutes total. (There's even a New York Times workout app based on the idea, called the 7-Minute Workout. More on thathere.)

Despite consuming far less time than a marathon training session, an interval workoutmay actually be healthierin the long run (pun intended), according tosome research done in the past decade.

A 2012 study comparing a group of runners who did traditional, continuous runs with a group of runners who did interval trainingfound that both groups achieved nearly the same results. There was one small difference, though: The interval trainers had better peak oxygen uptake, an important measure of endurance.

And arecent study in the journal Diabetologiafound that doing walking interval training — an hour of alternating between three minutes of brisk walking and three minutes of stopping — helped people with diabetes control their blood-sugar levels far better than simply walking at the same pace continuously.

Still not convinced?

Consider this: Distance running could actually be bad for you.

There's some evidence to suggest that prolonged, intense exercise — such as the type necessary in the weeks and months before a marathon and in the race itself — can have some unhealthy side effects, from reduced immune function to digestive issues.

Working the body to its maximum,some research shows, can reduce the body's natural ability to fend off upper-respiratory infections including colds and the flu. Short bouts of activity, on the other hand, improve immune function. Quick workouts appear to not only reduce your chances of getting sick, but also to reduce the severity of an illness when you do come down with something.

Up to 71% of long-distance runners also experience abdominal cramping and diarrhea. (The latter is so frequent that runners have a term for it: "runner's trots," aka "runner's diarrhea.") Many runners, even those without a history of it, experience acid reflux — a condition with effects like heartburn, indigestion, coughing, hoarseness, and asthma — during and immediately after a long run.

Here's what it all comes down to: Whether you stick to a long-distance routine or opt for a quicker, daily exercise plan, it's important to keep in mind that more is not always better.