Today we ruck. That just means we carry a heavy backpack around for a solid chunk of time while listening to something awesome. We are always aiming to train all the parts of our fitness spectrum. With the ruck, you'll get a combination of moderate heart rate and a very long time and distance. That combination is hard to get unless you are a well seasoned long endurance athlete. That's what we want today. The logistics of this thing could distract you, don't let them. Put some amount of weight on a comfortable backpack, get a good playlist going, and just walk wherever you can for at least an hour. 

I carried the 25-pound slam ball in my backpack on a cold afternoon in Oxford.