So is it true? Can we use exercise to control our metabolism?

這是真的嗎？我們能用運動來控制新陳代謝嗎？

[Body Stuff with Dr. Jen Gunter]

【珍‧甘特醫生談身體的五四三】

To answer that question, we have to first dig deeper into what metabolism is.

要回答這個問題，我們需要深入了解什麼是新陳代謝。

No surprise, metabolism is really complex, and scientists and researchers are still discovering many new things about it.

不意外，新陳代謝非常複雜，科學研究還陸續有新發現。

Very simply, metabolism is the set of chemical reactions in every cell of our body that harnesses energy to keep us alive.

簡單來說，新陳代謝是人體細胞中的一組化學反應，能控制能量讓我們活著。

So much of what happens in our bodies is metabolism,

我們身體裡發生的事有許多屬於新陳代謝，

making new cells is metabolism, growing hair is metabolism, and converting food into energy is metabolism.

造新細胞是新陳代謝、長頭髮是新陳代謝、轉化食物為能量也是新陳代謝。

The sum total energy of all the metabolic processes that occur throughout our body is measured in calories.

我們身體新陳代謝產生能量的總和是以卡路里來衡量的。

And surprisingly, exercise is usually a small percentage of our daily calorie burn.

令人驚訝的是， 運動通常只是我們每天消耗掉卡路里的一小部分。

Unless you're a professional athlete, most of our calorie expenditure is accounted for by our basal metabolic rate.

除非你是職業運動員， 否則我們大部分的卡路里消耗都是由我們的基礎代謝率決定的。

All the vital stuff we need to function, like having a heartbeat, growing hair, building cells and even blinking.

所有我們身體運作所需的要事， 例如心跳、長毛髮、製造細胞甚至眨眼。

That stuff takes up a big chunk of our energy.

這些機能用掉我們能量的一大部分。

So can we hack this equation in some way?

我們有辦法破解這方程式嗎？

Can we use exercise to speed up our metabolism so we burn more energy?

我們能用運動加速新陳代謝而消耗更多能量嗎？

Can we burn even more calories?

我們能消耗更多卡路里嗎？

Not just doing burpees, but while we're growing an eyelash, than before?

不只是做波比跳， 當我們長眼睫毛的時候， 也能比以前消耗更多卡路里嗎？

The answer is no.

答案是不能。

First of all, this is a misunderstanding of what fast versus slow metabolism really indicates.

首先， 這是對新陳代謝快或慢真正含義的誤解。

There's no clear link between thinner people and fast metabolism, and the same goes for larger people and slow metabolism.

苗條的人和快速的新陳代謝沒有明顯的關聯，胖的人和緩慢的新陳代謝也一樣沒有明顯的關聯。

In fact, if you look at the absolute numbers, people with larger bodies have faster metabolisms, meaning they burn more calories because larger bodies have more cells,

事實上，如果你只看數字，體型大的人新陳代謝比較快，意味著他們消耗更多卡路里， 因為大的體型有較多細胞，

which in turn are doing more to sustain the body.

需要消耗更多才能維持運轉。

Now, differences in metabolism between people with similar body sizes do exist, but the difference between fast metabolism and slow metabolism can be about 300 calories.

體型類似的人的確有新陳代謝的差異， 但是新陳代謝快和慢的差異大約只是 300 卡路里。

That's like two apples and a banana.

相當於兩個蘋果和一根香蕉。

How fast our metabolism works is mostly genetic and related to body size, but there's also age.

我們新陳代謝的速度主要決定於基因， 也和體型有關，年齡也有影響。

Our metabolic rate changes a few times over our lifespan.

我們的新陳代謝率在一生中會改變幾次。

We start with the metabolic rate of an infant.

起初是嬰兒的新陳代謝率，

Then there is a switch when we are toddlers, and then it's pretty stable during adulthood to age 60, when it changes again.

然後轉變到兒童時期，然後成年一直到 60 歲都相當穩定，然後再次改變。

Researchers evaluated the Hadza, a group of people in Tanzania who live a traditional hunter gatherer lifestyle.

研究人員評估了坦尚尼亞的哈札人， 他們仍過著捕獵採集的原始生活。

And yet, when you control for body size and age, they burn a similar amount of calories a day as an average American adult.

但是，當你控制體型和年齡的因素，他們每天消耗的卡路里和美國平均的成年人很類似。

It seems that calories out is a pretty fixed number, and it appears that our bodies have limits.

似乎卡路里的消耗 是一個相當固定的數字， 而且我們的身體也有極限。

If we exercise harder, at first we may expend more energy, but over time, our metabolism will find ways to conserve.

如果我們更賣力運動， 一開始可能會消耗掉更多能量， 但是過了一段時間， 們的新陳代謝會找到辦法保存能量。

Here's what I'm getting at.

要講到我的重點了。

The point of our metabolic system is to manage energy, not to manage weight.

我們新陳代謝系統的目的是管理能量，不是管理體重。

So if you read an article or hear a so-called expert inviting you to boost your metabolism,

所以，如果你讀到一篇文章， 或聽到所謂的專家邀請你去促進新陳代謝，

remember that's just marketing speak rooted in a weight loss culture, and it just isn't true.

記住，那只是扎根於減重文化的行銷之詞，並不是真的。