Comparing Apples and Oranges

One of the reasons that hard-core runners don’t do more cross-training is because they don’t know how to compare it to their running. The major way that they track their progress is to recite their weekly running mileage to anyone who will listen. A five-mile run is a five-mile run is a fivemile run, so if you only run, keeping records is pretty easy. But what about a two-hour bike ride, a half hour in the pool, or 45 minutes on a stair machine? How do these compare to running miles?
My advice is different than what most people are going to tell you. I say, don’t worry about it. That’s because I’m recommending that you cross-train to add to your running, not replace it. In that case, there’s not much point in obsessing about whether three cycling miles equals one running mile and how many minutes on a rowing machine equal one mile of running. To paraphrase Sigmund Freud, sometimes a two-hour bike ride is just a two-hour bike ride.