My running ambition is to keep doing it until I'm way past the point where I have any business running. Just to keep doing it throughout my whole life—to stay fit and feel good.

Coming down under a parachute is quite different as well. You hit the ground pretty hard, but all the systems work very well to keep it from hurting, so it doesn't even hurt when you hit. It was a great experience to be able to do both.

Even though I knew I was inside the space shuttle getting ready to go fly, something about it wasn't completely real up until we got the call at about one minute to go, to close and lock our visors and start our oxygen flow. People often ask me, "What did it feel like right at the moment of launch?" And they're surprised when I tell them actually what I felt was relief. It wasn't like being anxious or scared or anything. It was relief because this is something I had wanted to do my whole life and now that the boosters had lit, we were on our way to go do it and nothing was going to stop us.

You saw Britain back in the early days of sailing ships. They were the sea power, the controlled the seas and they had colonies all over the world and then you can look at history and watch the way that their empire kind of crumbled. I certainly don't want that to happen to the United States in space technology.

As far as Russia goes, they've been our partner for a long time now, since the early '90's. So you know, what's that, that's more than 15 years. And there have been times where things were a little tense, a little testy, but by and large, the partnership has been very successful. To give you two examples of that, when the Columbia accident occurred, the Russians supported us with their spacecraft faring our astronauts, including me, to the space station and also supplies.

The United States, Russia, and China are the only three countries in the world that can launch astronauts into space. Mostly in the U.S. you see some companies trying to launch private commercial people into space, but nobody's done it yet. The only private vehicle that's made it into space so far is Spaceship 1 in 2004, and that was an effort that was funded by one of the Microsoft founders, and he spent about $20 million to develop this spacecraft to do a sub-orbital flight. And it's not the same as going into orbit, but it was a huge first step.

I attended a big human space flight conference in Beijing and I was going as myself. And really, there weren't any NASA astronauts there, I was the only so-called American Astronaut there. We had astronauts from most of the other countries, certainly from Russia, from France, from Japan, several other countries, but it was a little bit odd because here we are at an international gathering of a lot of astronauts and I'm talking about somewhere upwards of 30 or so astronauts, and I'm the only American. And I wasn't even there in an official capacity.