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Can Caffeine Really Cause Insanity?

kira86 于2010-10-26发布 l 已有人浏览
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From babies to body builders, we all have muscles. They grow, they bulge, they stretch and sometimes

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From babies to body builders, we all have muscles. They grow, they bulge, they stretch and sometimes they even painfully pull. But for all the work they do for us, we are still unable to crown one as "the strongest muscle."

Instead, a few muscles could claim the title, depending on how strength is measured.

If the title goes to the muscle that can exert the most force, the victor would be the soleus, or the calf muscle, according to Gray's Anatomy, the anatomy textbook. Without this muscle, we wouldn't be able to stand, walk, run or shake our bodies on the dance floor. If the soleus was not continuously pulling, we would always be falling over ourselves (although some of us tend to do that from time to time anyway).

But perhaps the title should go to the muscle that exerts the most pressure. Pressure is different from force — pressure takes into account the area over which a force is exerted. The muscle that takes the prize for delivering the greatest amount of pressure is the masseter, or the jaw muscle, according to the book "Clinical Oral Science" (Reed Educational and Professional Publishing, 1998).

In 1986, Richard Hofmann of Lake City, Fla., achieved a bite strength of 975 pounds (442 kilograms) for two seconds, setting a Guinness Record. Talk about jaw dropping! The jaw is able to clench and chew because of the masseter muscle.

Others may argue the muscles used in childbirth are the most powerful. To be specific, the ability of the myometrium, or the uterine muscle, to contract and relax makes human birth possible. But because these muscles are not often used and highly depend on an interaction of hormonal and biochemical factors, some discount the myometrium as the strongest muscle.

When it comes to versatility, perhaps the tongue is the strongest muscle. Its combination of elasticity and forcefulness gives us the ability to speak, eat and kiss – all things very desirable on a first date. However dexterous it may be though, its power does not match that of muscles such as the soleus.

If slow and steady wins the race, the heart is certainly a contender for the title. Electrical impulses in the myocardium, the heart's muscular wall, keep your heart beating. When it contracts, the muscle pumps about 2 ounces (59 milliliters) of blood, and is constantly working over a lifetime. Beating about 40 million times a year, a person's heart will beat approximately 2.5 billion times by the time of their 70th birthday.

The single biggest muscle in the human body is the gluteus maximus, or the buttocks. This muscle helps keep the torso erect, and stronger glutes allow a person to jump higher and sprint faster.

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