Written by Science Knowledge on 2:04 AM

Muscles are the ultimate self-tuning organs. If you rely on them to perform daily labor, they respond by growing bigger and stronger. But if you don’t give them anything useful to do, they shrink. That way, your body saves on the metabolic cost of keeping them alive. After all, the more muscles you have, the more calories you burn, even at rest—and your frugal body isn’t willing to waste all that valuable fuel.

In the modern world, where the hardest labor many people do is to reach across the sofa for the TV remote, our daily activity just isn’t enough to keep our muscles healthy. To fill the gap, we created exercise—basically, a practice in which we lift heavy things and then put them down in exactly the same place, or run like crazy on a machine without actually going anywhere.

Exercise is a thoroughly modern invention. Thousands of years ago, the balance between rest and activity was almost exactly the reverse of what it is today. People spent most of their lives straining their bodies, and if they had a moment of free time, the healthiest thing they could do was rest their weary muscles. Today, we spend most of our lives sitting in one place and thinking hard (or at least trying to look like we’re thinking hard). When we have time off, we use exercise to build and maintain healthy muscles— or, from a more cynical perspective, to give the illusion that our bodies are being put to good use. But if you want to spend your twilight years strong, hearty, and with all the muscular strength you need to pull your bottom off a toilet seat, you need a regular regimen of exercise.

As you probably know, there are two basic types of exercise:

• Aerobic exercise. This is the heart-pounding, fast-breathing sort of exercise you perform when jogging, swimming, cycling, or jumping on a trampoline. A regular regimen of aerobic exercise strengthens your heart, improves your lung capacity, and increases your endurance. It has a cascade of other potentially beneficial effects on the body, too—for example, it can improve your coordination, boost your metabolism, and burn fat. However, aerobic exercise isn’t the best way to build your muscles.

• Strength training. This is the intense muscle-straining exercise you perform when lifting weights or doing sit-ups. It makes your muscles contract much more forcefully, but for much shorter periods of time. Although a regular regimen of strength training won’t improve your stamina, it will pump up your muscles.

Both types of exercise are important, and their benefits are complementary. You’ll learn more about aerobic exercise on page 172, when you explore the heart. In the following sections, you’ll learn more about how muscles develop, and you’ll get some practical tips to help with your own strength training.

Source of Information : Oreilly - Your Body Missing Manual

Related Posts by Categories

  1. 0 comments: Responses to “ Exercise ”

About Me

In its broadest sense, science (from the Latin scientia, meaning "knowledge") refers to any systematic knowledge or practice. In its more usual restricted sense, science refers to a system of acquiring knowledge based on scientific method, as well as to the organized body of knowledge gained through such research.

Fields of science are commonly classified along two major lines: natural sciences, which study natural phenomena (including biological life), and social sciences, which study human behavior and societies. These groupings are empirical sciences, which means the knowledge must be based on observable phenomena and capable of being experimented for its validity by other researchers working under the same conditions.

You are welcome to contact me and leave your comments in my Blog.

Science Knowledge

Want to subscribe?

Science Knowledge

Grab this Headline Animator

Enter your email address:

Delivered by FeedBurner