[Scott Johnston]

That uphill test can be done with our without a pack.  Of course the results (with and without) will probably quite different in terms of HR and speed. Whether you choose to wear a weighted pack is up to you.   A weighted pack AnT test would be useful for comparing with a AeT on similar terrain without weight so you can see the spread between AeT and AnT.

An uphill AnT test, especially if it is steep (>10%), will probably not be helpful in establishing an AnT HR to compare with a flat running AeT test.  The modalities are enough different that about 50% of the people will have very different uphill AnT and flat running AnT.

If much of your running is on the flat I would recommend doing the AnT test running on the flat.

If you are training for mountaineering, flat running is a good way to accumulate a goof volume of aerobic base training but you should definitely include a significant volume of vertical each week using natural terrain or gym machines.

I hope this helps,

Scott