@jmaunsell thanks so much for reaching out about trekking poles! We've had some really good conversations here in the community on this exact topic - you can find a few one of those conversations here.

In addition, we have some community members who know a lot about trekking poles - we'll tag them to weigh in too! @Minnie @Wanderer @mathineer @Philreedshikes @CajunHiker 

Also, here's a great resource in our Expert Advice on How to Choose Trekking Poles.

And finally, a few thoughts:

• Telescopic are likely a better choice for what you're describing, as you can shorten them for the uphills and lengthen them for the downhills.
• Shock absorption can be really helpful if you're covering a lot of miles and/or using them repetitively
• And then there are some personal choices, like material used in the grip (cork, rubber, foam)

Hope this helps to get you started!