Have you noticed that people have taken to bragging, "I walk or I run 5K every day." Well, I was impressed until I realized that a K is not even a mile but .62 of a mile and 5K is only 3 miles.
I brisk walk a minimum of 5 miles every day, so 3 miles doesn’t impress me overmuch. Being an American, I use miles, and don’t really get why everyone is using metric for their running or walking. Maybe because, well, 5K does sound more impressive than 3 miles.
I’ll continue with my miles except when I respond to someone touting their 5K. My 8K trumps their 5 everyday.