Only 11% of rental units allow big dogs.

But what exactly is a big dog?

The answer could mean the difference between life and death.

Control F is a new podcast about the data that companies and the government use to shape our daily lives.

Listen to Control F from KOWW in Seattle, a member of the NPR network.

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This Friday, the Olympic Caldern will be lit, signaling the start of the winter games in Italy.

We will see figure skating, ice hockey, and of course, the sliding sports,

bobsled, luge, and its sister sport skeleton, where you slide down the ice track headfirst,

going up to 80, sometimes 90 miles per hour. To me, it felt like the closest thing you could

get to flying. It was like a roller coaster that you could control. But then on the bad days,

it felt like a minute of a car crash. Alia Snyder was a competitive skeleton athlete. The sport

gave her a huge adrenaline rush. But there was something else too. Some runs left her feeling

shaky afterwards, disoriented. Then it became more clear over the course of the day that I

would have trouble concentrating, I would be feeling more nauseous, I would just kind of feel more

irritable, have trouble with lights, things like that. And she was told back then, don't worry,

it's normal.

Oh, you know, everybody's kind of a little bit concussed all the time.

But nowadays, there is a term for the symptoms that can follow a really shaky or high G-force run.

And that term is sledhead, the dizziness, nausea, exhaustion, and cognitive problems

that eventually damaged Aaliyia's brain and body.

My head didn't tolerate the vibrational forces. And I just kept training through a lot of symptoms that I kept

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