Pick a big hill, run up it...............repeat. Over and over and over, etc. HA!
I usually do a bigger hill near my mom's house, but today I chose a somewhat smaller hill, had to twice as many to make up the amount of the larger hill.
I brought Sebastian out with me today, told him that he didn't have to run, but wasn't allowed to stop. I think he got about 3 done. Which I am happy with since he didn't complain!
I did 8, which amounted to 4 miles. 38 minutes. Eh.