@rsharp I realized that I needed to get more into this for the Trailmetrics project I’m working on right now, since “10mi” and “10mi with 2000ft of cumulative elevation gain” are quite different things.

It looks like there’s no definitive standard on how to do this, but a lot of rules of thumb. Here’s one thread discussing the issue, and here’s another blog post.

One thing that looks pretty set is that most people take a baseline of +1mi equivalent for every 1000ft of elevation gain and then adjust for their own particular experience. Lacking any other convincing evidence, I think I’ll just go with that.

That makes HARM the following: (((Masshiker+pack / Masshiker) x ((cumulative elevation gain in ft/1000) + distance)) x (mortality rate x 2)) / miles. Mortality rate is doubled because our base design of 1.0 Powells has a mortality rate of 0.5.



Slightly modified because otherwise the numbers are so small as to be meaningless to actual readers (multiplied it all by 1000).

HARM = (((Masshiker+pack / Masshiker) x ((cumulative elevation gain in ft/1000) + distance)) x (mortality rate x 2) x 1000 )/ distance

Why multiply by 1000? Guess how many miles (roughly), John Wesley Powell’s expedition was?

Let’s run the example of @rsharp and my hike up the Belly River in September:

  • Mass – I was carrying a pack that meant I measured 1.24 times my normal body mass.
  • Distance – 25.67mi
  • Cumulative elevation gain – 4495ft
  • Mortality rate for Glacier national park – 260 deaths out of 102,082,878 through 2015 = 0.0000025.

So that makes our example calculation: (1.24mass x (25.67mi + 4495ft/1000) x 0.0000025 x 2 x 1000) = 0.186 total Powells and our HARM = 0.186 Powells / 25.67mi = 0.00726 Powells/mi. Note: HARM is also expressible in badassitude/mi.
Let’s compare that to the original: 1.0mass (in a boat, no carrying) x (1000mi + 0 gain in a boat) x 0.5 x 2 x 1000mi) = 1 million Powells / 1000mi = 1000 Powells/mi

Think that’s starting to look better to me @rsharp.

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