How rollercoasters affect your body - Brian D. Avery

譯者: Lilian Chiu 審譯者: Helen Chang

In the summer of 1895, crowds flooded the Coney Island boardwalk

在 1895 年夏天，

康尼島的木棧道上滿是人群，

to see the latest marvel of roller coaster technology:

他們搶著要看看最新的 雲霄飛車技術有多神奇：

the Flip Flap Railway.

就是「搖擺鐵路」。

This was America’s first-ever looping coaster

它是美國最早的轉圈飛車——

– but its thrilling flip came at a price.

但它那刺激的翻轉是有代價的。

The ride caused numerous cases of severe whiplash,

這組飛車曾經造成許多 嚴重揮鞭症候群、

neck injury and even ejections,

頸部受傷，甚至彈出的意外，

all due to its signature loop.

原因都是它主打的轉圈設計。

Today, coasters can pull off far more exciting tricks,

現今，雲霄飛車的花招更炫了，

without resorting to the “thrill” of a hospital visit.

且不附帶後續要進醫院的 另一種「刺激」。

But what exactly are roller coasters doing to your body,

但雲霄飛車對你的身體 到底有何影響？

and how have they managed to get scarier and safer at the same time?

它們要如何能在同時 變得更安全又更駭人？

At the center of every roller coaster design is gravity.

雲霄飛車設計的核心是重力。

Unlike cars or transit trains,

和汽車或捷運不同，

most coasters are propelled around their tracks

大部分雲霄飛車能在軌道上推進，

almost entirely by gravitational energy.

靠的幾乎全是重力能。

After the coaster crests the initial lift hill,

在雲霄飛車爬上了第一個高峰時，

it begins an expertly engineered cycle –

專業打造的循環就開始了——

building potential energy on ascents and expending kinetic energy on descents.

上升時會建立位能， 下降時會消耗動能。

This rhythm repeats throughout the ride,

這個節奏在整趟過程中不斷重覆，

acting out the coaster engineer’s choreographed dance

演出雲霄飛車工程師

所編排的重力能之舞。

of gravitational energy.

But there’s a key variable in this cycle that wasn’t always so carefully considered:

但在這個循環中有一個關鍵變數 不見得總是被小心地考量到：

you.

就是你。

In the days of the Flip-Flap,

在搖擺鐵路時期，

ride designers were most concerned with coasters getting stuck

飛車設計師最擔心的是飛車

somewhere along the track.

在軌道的某個地方卡住。

This led early builders to overcompensate,

這導致了早期的建造者會過度補償，

hurling trains down hills

讓列車更猛地衝下坡， 在抵達終點站時用力拉煞車。

and pulling on the brakes when they reached the station.

But as gravity affects the cars, it also affects the passengers.

但重力不只會影響列車， 也會影響乘客。

And under the intense conditions of a coaster,

在雲霄飛車的緊張條件下，

gravity’s effects are multiplied.

重力的影響有加乘的效果。

There’s a common unit used by jet pilots,

有一種噴射機飛行員、 太空人、雲霄飛車設計師

astronauts,

and coaster designers called “g force”.

都常使用的單位，叫「G 力」。

One G force is the familiar tug of gravity you feel when standing on Earth

1G 的力就是你站在地球上時 熟悉的重力牽引——

– this is the force of Earth’s gravitational pull on our bodies.

這就是地球對我們的身體 所產生的重力拉力。

But as riders accelerate and decelerate,

但隨著飛車乘客加速和減速，

they experience more or less gravitational force.

他們會經歷到更高或更低的重力。

Modern ride designers know that the body can handle up to roughly 5 Gs,

現代的飛車設計師知道 人體能承受到大約 5G，

but the Flip-Flap and its contemporaries routinely reached up to 12 Gs.

但搖擺鐵路和那時的 其他飛車經常會衝到 12G。

At those levels of gravitational pressure,

在那種程度的重力壓力下，

blood is sent flying from your brain to your feet,

血液會從你的大腦衝到你的腳，

leading to light-headedness or blackouts

在大腦拼命想保持意識時

as the brain struggles to stay conscious.

導致眩暈或昏倒。

And oxygen deprivation in the retinal cells impairs their ability to process light,

視網膜細胞缺氧

會讓那些細胞無法處理光線，

causing greyed out vision or temporary blindness.

造成視線灰暗或暫時性失明。

If the riders are upside down, blood can flood the skull,

如果乘客倒過來， 血液可能會衝向頭部，

causing a bout of crimson vision called a “redout”.

造成視線變紅的「紅視」發作。

Conversely, negative G’s create weightlessness.

反過來，負數的 G 力造成失重。

Within the body,

在身體內，短期的失重 幾乎是無害的。

short-term weightlessness is mostly harmless.

It can contribute to a rider’s motion sickness

它可能會造成乘客暈車，

by suspending the fluid in their inner ears

因為會讓內耳中 協調平衡的液體懸浮起來，

which coordinates balance.

But the bigger potential danger

但更大的潛在危險和刺激

– and thrill –

comes from what ride designers call airtime.

來自飛車設計師所謂的空中時間。

This is when riders typically experience seat separation,

也就是乘客通常 會感覺到和椅子分離，

and, without the proper precautions,

且，若沒做好事先預防， 就會彈出去。

ejection.

The numerous belts and harnesses of modern coasters

現代雲霄飛車用了 許多安全帶和保險帶，

have largely solved this issue,

大部分解決了這個議題，

but the passenger’s ever-changing position can make it difficult

但乘客的位置一直在改變，

可能很難判斷要怎麼捆綁。

to determine what needs to be strapped down.

Fortunately, modern ride designers are well aware

幸運的是，現代 雲霄飛車設計師都知道

of what your body, and the coaster,

你的身體和雲霄飛車能承受多少。

can handle.

Coaster engineers play these competing forces against each other,

雲霄飛車的工程師 利用這些力來互相抗衡，

to relieve periods of intense pressure with periods of no pressure at all.

用完全沒有壓力的一段路 來緩和壓力極大的一段路。

And since a quick transition from positive to negative G-force

因為從正的 G 力 快速轉換為負的 G 力

can result in whiplash, headaches, and back and neck pain,

可能會造成揮鞭症候群、 頭痛、背痛、頸痛，

they avoid the extreme changes in speed and direction

他們會避免使用以前 刺激飛車常見的做法：

so common in thrill rides of old.

速度和方向的急劇改變。

Modern rides are also much sturdier,

現代飛車也比較堅固，

closely considering the amount of gravity they need to withstand.

很仔細地考量了飛車 需要承受的重力。

At 5 G’s, your body feels 5 times heavier;

在 5G 時，你的身體 感覺起來有 5 倍重；

so if you weigh 100lbs,

如果你的體重是一百磅，

you’d exert the weight of 500 lbs on the coaster.

你在雲霄飛車上 要承受五百磅的體重。

Engineers have to account for the multiplied weight

工程師在設計雲霄飛車的支撐時，

of every passenger when designing a coaster’s supports.

要考慮到每一位乘客加乘的體重。

Still, these rides aren’t for everyone.

不過，仍然不是人人 適合乘坐雲霄飛車。

The floods of adrenaline, light-headedness, and motion sickness

腎上腺素大量分泌、

頭暈目眩、暈車

aren’t going anywhere soon.

暫時都還是會存在。

But today’s redundant restraints, 3D modeling and simulation software

但現今，過多的限制、 3D 建模，以及模擬軟體

have made roller coasters safer and more thrilling than ever.

已經讓雲霄飛車變得 比以前更安全、更刺激。

Our precise knowledge about the limits of the human body

我們對於人體限制的精確知識

have helped us build coasters that are faster, taller, and loopier

協助我們打造出更快、更高、 更多轉圈的雲霄飛車——

– and all without going off the rails.

且都不會出軌。