A bit off topic, but does involve Microsoft Excel…You runners, swimmers and bikers out there may occasionally do interval training in order to increase your speed. I’m always trying to answer the following question: how fast do I need run to get time X in a race of distance Y? And how fast do I have to run shorter interval Z to see what that pace feels like? I made an Excel file that makes such extrapolations easy. You can time yourself running a short interval and see what time you would get if you kept up that pace for a whole race. Download it with the link earlier in this post or using the Downloads page on this blog.