One thing clear to me on this marathon training cycle is that getting in a lot of miles is probably not going to happen. It’s one reason I went ahead and joined the gym near my home: I need to do more to fill in the blanks with cross training. I’ll hit my key workouts whether outdoors or indoors, and then have a variety of indoor options with which to fill in the blanks.
Filling in the blanks however requires some analysis. People cross train, but people don’t have a firm basis from which to equate their cross training to the needed aerobic development.
How much work on the bike or elliptical equals one mile of easy running? Most do an indeterminate amount of cross training, but beyond knowing that it helps some with training, they have no idea how many miles or how much progress it has helped make them.
(I will also note that, while some writers and coaches think it so, I don’t consider treadmill running cross training. I realize at a zero incline, with a consistent surface, and with no wind resistance… running on a treadmill could be easier than regular running. However, there are enough equalizing factors I’ll discuss another time that can and usually do make it as difficult, sometimes more difficult, than regular running. Plus, you still are bearing all of your weight at a higher speed and intensity, as you do with running. So, I consider miles run on the treadmill equal to regular running miles.)
What’s the best way to figure out how much value, how much volume, a cross training workout provided to your training? It’s a question I’ve dabbled with over time, and wrestled with more in recent memory, especially now that I’m cross training more frequently at the gym.
I think the best way to figure this out is: