As a tennis player, or any professional athlete, our career has a shelf life. I don't want to waste any opportunities, I don't want to look back on it when I'm 45 and think I could have done a lot more.

I didn't know I could even be a professional tennis player, honestly. All this is actually very, very unexpected.

A lot of times when I'm confident and relaxed on the court, I'm going to be a pretty tough out. But when I'm not so confident and not so relaxed, I tense up and my balls fall short and everything. It just sort of unravels.

In the past, I've played where I only just rely on my serve.

Sleephackers go to bed with sensors on their wrists and foreheads and maintain detailed electronic sleep diaries, which they often share online. To shift between sleep phases, sleephackers experiment with various diets, room and body temperatures, and kinds of pre-sleep physical exercise.

What's happened with the over-the-counter birth control issue is that the Democrats didn't see it coming. They think that they've got a monopoly on talking to women from the waist down. Anything that has to do with reproduction and birth control and abortion - they call it women's health, then they call it women's issues.

Health care is a need; it's not a commodity, and it should be distributed according to need. If you're very sick, you should have a lot of it. If you're not sick, you shouldn't have a lot of it.

The American people want change. They don't want the same old health care system that's not affordable, that doesn't offer coverage to everybody, that keeps escalating in cost. And what we've seen from the Republicans is, really, a desire to have the status quo.