Are Trail Runners Really Runners?

We have been having an ongoing discussion with some of our friend around running versus walking hills on trails. On one side (including my wife and I) is the group that does trail runs on a regular basis and will walk most hills.  The reasoning is that, from an endurance standpoint, you want to conserve the additional energy that you would expend running up a hill for the flats and downhill.  On the other side, is the group who do a lot of road races, and run every run like it is a flat marathon - all out (a very anaerobic style).

900 Elevation within the first mile at Brazen's Wildcat 5K, 10K, and Half-Marathon

What makes runs interesting is when these two worlds collide.  I recently received a text from my road running buddy who has just started running trails wanting to get the phone number of my buddy who runs ultras.  After the first run, my road running buddy was amazed at how "slow" my ultra friend was.  Keep in mind, my road running buddy's marathon PR is under 4 hours.  My ultra friend mentioned, however, that about mile 7 on a 13 mile trail run the road running buddy started to really slow down.

It is the same with the road running buddy's wife.  She has been running with my wife for a few years now.  My wife loves the trails, especially since our son has begun kindergarten.  They have a standing running date every Thursday and they rotate which week on who picks the running course.  The Beast (my wife's nickname for her since she runs so fast) typically wants to run flat trails, like the Iron Horse Trail here in Walnut Creek.  She typically leaves my wife in the dust.  The interesting thing is that the Beast is hurt on a regular basis.

Half Marathon with 3,800 Elevation gain....hmmm.

It is so interesting that the running or walking hills (or mountains) and the speed of a trail runner can be a polarizing discussion.  In fact just this past week, Trail Runner Nation had a Podcast that discussed whether someone should call a 100 mile run should actually be called a run if you are walking anywhere from 50% to 90% of the race.  What was even more interesting to me was how an East Coast person (which is used to a lot of flat 100-milers) looks at 100 mile Ultras verses someone from the mountain states or West Coast.

Clearly a trail runner looks at a run more strategically than a regular road run.  There is elevation gain, how technical the terrain, the length of the run, when to refuel (an aid station every 4 to 10 miles isn't very forgiving), etc. for a trail runner takes more precedence than the time it takes.  

You can compare the both types of runs to NASCAR and Formula One Races.  Both are races; one is just faster than the other.  But when to change the tires, fuel up, as well as the speed the course will allow are different between the two.

So are trail runners really runners?  Of course we are, we just know when to conserve our energy to go the distance.  Is a road runner foolish for running hills?  They can if they want...but that is typically why there aren't many road race ultras.