CROSS-TRAIN·ING
The action or practice of engaging in two or more sports or types of exercise in order to improve fitness or performance in one's main sport. *source: dictionary.com

In other words, cross-training is basically a way to improve your running without straight up running. Here is a list of cross-training activities that will mimic running form and improve your endurance so you can go ALL. THE. WAY.

CROSS-TRAINING FOR RUNNING
Cycling / Spinning
Elliptical
Stair-Stepper
Walking / Hiking
Swimming
Rollerblading
Cross Country Skiing

If you are doing workouts that are not on this list, don’t sweat it - figuratively speaking, of course. These types of activities (think yoga, pilates, boxing, etc.) are still great for your overall fitness, but may need to be put on hold depending on your specific running goal.