There is no real substitute for running up and down hills
A little variety in running is always welcome.
Whether it is a different route, trying to run hills, speed work or maybe trying a longer distance variety has benefits. There are occasional arguments as to which of the running best benefits fitness, weight loss or calories burned.
When organizers advertise in their flyer that there are a few hills on the course, a number of runners will opt to try a race where the course is flat and fast.