What makes muscles grow? - Jeffrey Siegel

譯者: Pechow Z 審譯者: Max Chern

Muscles.

肌肉

We have over 600 of them.

我們有超過600塊肌肉

They make up between 1/3 and 1/2 of our body weight,

佔身體重量的三分之一到二分之一

and along with connective tissue,

與結締組織

they bind us together, hold us up, and help us move.

將身體連結在一起， 讓我們站，讓我們動

And whether or not body building is your hobby,

無論健身是不是你的興趣愛好

muscles need your constant attention

肌肉都需要你的持續關注

because the way you treat them on a daily basis

因為你每日使用的方式

determines whether they will wither or grow.

可決定肌肉的消長

Say you're standing in front of a door, ready to pull it open.

比如說你站在門前面，準備拉開門

Your brain and muscles are perfectly poised to help you achieve this goal.

你的大腦和肌肉會 完美協調幫你達成目標

First, your brain sends a signal to motor neurons inside your arm.

首先，你的大腦會給手臂 的運動神經元發送信號

When they receive this message, they fire,

當它們接到信號，它們就會啟動

causing muscles to contract and relax,

造成肌肉收縮和放鬆

which pull on the bones in your arm and generate the needed movement.

拉動手臂的骨骼作出相應的行動

The bigger the challenge becomes, the bigger the brain's signal grows,

動作的挑戰越大， 大腦發送的信號就越強

and the more motor units it rallies to help you achieve your task.

越多的運動單位會聚集幫助你達成任務

But what if the door is made of solid iron?

但是如果這扇門是鐵門呢？

At this point, your arm muscles alone

現在，單憑你手臂的肌肉

won't be able to generate enough tension to pull it open,

是不可能產生足夠的拉力來開門的

so your brain appeals to other muscles for help.

所以你的大腦會叫其他肌肉來幫忙

You plant your feet, tighten your belly, and tense your back,

你站穩腳，收腹，挺直腰

generating enough force to yank it open.

產生足夠的力量使勁拉開門

Your nervous system has just leveraged the resources you already have,

你的神經系統剛剛挪用身體現成的資源

other muscles,

其它肌肉

to meet the demand.

來滿足需求

While all this is happening,

當這一切發生時

your muscle fibers undergo another kind of cellular change.

肌肉纖維進行另一種細胞改變

As you expose them to stress, they experience microscopic damage,

當肌肉承受拉伸，會發生微細的損傷

which, in this context, is a good thing.

在這種狀況下，是一件好事

In response, the injured cells release inflammatory molecules called cytokines

對此反應，損傷的細胞釋放出 稱為“細胞因子”的發炎分子

that activate the immune system to repair the injury.

用來激活免疫系統和修復損傷

This is when the muscle-building magic happens.

這就是增長肌肉的魔法

The greater the damage to the muscle tissue,

肌肉組織的損傷越大

the more your body will need to repair itself.

身體就會進行越多的自我修復

The resulting cycle of damage and repair

損傷和修復導致的循環

eventually makes muscles bigger and stronger

最終使肌肉更大更強壯

as they adapt to progressively greater demands.

以便可以適應逐漸更大的需求

Since our bodies have already adapted to most everyday activities,

因為我們的身體已經 適應大多數的日常活動

those generally don't produce enough stress

通常日常活動就無法產生足夠的壓力

to stimulate new muscle growth.

來刺激新的肌肉生長

So, to build new muscle, a process called hypertrophy,

所以，增長新的肌肉， 所謂“肥厚增生”的過程

our cells need to be exposed to higher workloads than they are used to.

必須承受比平常更高的工作負荷

In fact, if you don't continuously expose your muscles to some resistance,

事實上，如果你不持續讓肌肉承受一些阻抗

they will shrink,

肌肉會縮小

a process known as muscular atrophy.

這個過程稱為“肌肉萎縮”

In contrast, exposing the muscle to a high-degree of tension,

相對的，讓肌肉承受高強度張力

especially while the muscle is lengthening,

特別是肌肉拉伸時

also called an eccentric contraction,

也被稱為“離心性收縮”

generates effective conditions for new growth.

可為新的肌肉生長產生有效的條件

However, muscles rely on more than just activity to grow.

然而，肌肉增長不只是 依賴助長生長的活動

Without proper nutrition, hormones, and rest,

沒有合適的營養、賀爾蒙，和休息

your body would never be able to repair damaged muscle fibers.

身體永遠不能修復受損的肌肉纖維

Protein in our diet preserves muscle mass

飲食中的蛋白質能維持肌肉的質量

by providing the building blocks for new tissue

藉著以氨基酸的形式，提供 組成單位給新生肌肉組織

in the form of amino acids.

藉著以氨基酸的形式，提供 組成單位給新生肌肉組織

Adequate protein intake, along with naturally occurring hormones,

足量的蛋白質攝入， 再加上天生的荷爾蒙，

like insulin-like growth factor and testosterone,

比如類胰島素生長因子和睾固酮

help shift the body into a state where tissue is repaired and grown.

可協助身體進入組織已 修復和生長的狀態

This vital repair process mainly occurs when we're resting,

這個重要的修復過程 主要發生在休息的時候

especially at night while sleeping.

尤其是晚上睡眠時

Gender and age affect this repair mechanism,

性別和年齡也會影響修復機制

which is why young men with more testosterone

這就是為什麼有較多睾固酮的年青人

have a leg up in the muscle building game.

在肌肉增長有優勢

Genetic factors also play a role in one's ability to grow muscle.

基因因素也會影響一個人增長肌肉的能力

Some people have more robust immune reactions to muscle damage,

有些人對肌肉損傷有更加強大的免疫反應

and are better able to repair and replace damaged muscle fibers,

而且對損傷的肌肉纖維 有較佳修復和替換的能力

increasing their muscle-building potential.

增大增長肌肉的潛能

The body responds to the demands you place on it.

身體會對你的需求做出反應

If you tear your muscles up, eat right, rest and repeat,

如果你撕裂肌肉，補充營養， 好好休息，持之以恆

you'll create the conditions to make your muscles as big and strong as possible.

你將創造使肌肉儘可能 變大變強壯的條件

It is with muscles as it is with life:

肌肉增長就和生命一樣

Meaningful growth requires challenge and stress.

有意義的成長需要挑戰和壓力