Pay the money, buy more space

A transatlantic flight's "extra legroom" seat costs about $140 each way from the U.S., so it's almost $300 round-trip. That's a big cost.

Is it worth it?

Yes.

Here's why.

When you arrive at your destination, you want to hit the ground running - collect your carry-on and personal items (hopefully with no checked luggage), exit the airport and start seeing sights. No delays. Very efficient.

This is hard to do when your body is already screaming from being twisted and torqued every which way in a tight seat for 8 hours or longer.

I don't recommend the exit rows unless you qualify under every requirement, because it's a matter of life and death. You need to understand what a flight attendant might be shouting at you in a chaotic situation, with a fair bit of screaming (in your native language or in another language); a lot of scrambling will be happening at the same time.

Similarly, I don't recommend First Class, because it's just so expensive and damaging to the planet for one person to demand that level of emissions, unless of course you have a physical or mental challenge that requires that much extra room for the safety of everyone else.

But most flights offer, in addition to exit rows and First Class, something called "extra legroom." It's usually as roomy as an exit row, at the same cost - check both of these - and for that amount of money, you get many more inches of extra space. Usually, you can stretch out your legs or even stand up without intruding into anyone else's personal space. This means that you arrive at your destination more rested and more ready to start your new adventure.

"Pre-game" with some pain reliever (possibly with the addition of caffeine) and some antacid, and exit the plane with confidence.

You're on your way!