Can you believe it's only a week until we complete our fitness challenge? Don't panic -- we have a great way for you to test your mettle for the final day, and it's part of a simple, doable workout.

If you've been meaning to start running, or to take your running more seriously, today is your lucky day. We're launching a new challenge that will unfold over the next seven weeks, with the goal of getting you ready to run your first, or fastest, 5K.

As soon as I was able to run, I wanted to run faster. It's been a journey with a lot of ups and downs, but it really is possible to start as a slow runner and, well, become a lot less slow. I'm no Olympian, but I'm fast enough to occasionally win age group medals at local races. Here's my story.