For me, the most beneficial effect of trekking poles is balance in rugged terrain - especially going downhill with a heavy pack. If they save you from just one fall, they're worth the investement. Cannot begin to count the number of stumbles, slips or trips over the years that would have resulted in a full fall if not for poles.
I use trekking poles all the time - light dayhikes to heavy backpacks. Last year I read that constant use of trekking poles may degrade your natural balance, so I went for a few hikes without them. I also do some occasional technical climbing and the thought of any deterioration in balance concerned me. I think it was my third or fourth hike without poles when a mild slip on a section of wet slabby granite turned into a broken big toe, multiple contusions, and several weeks of inactivity till the toe healed.
Screw the theory of possible balance degradation - poles go with me all the time now. Period. My personal favorites are the Black Diamond Trail Shocks. Close to 1000 miles on these babies - beat to hell and chewed gnarly by marmots, but still going strong.
Sidebar: Knowing how to use trekking pole wrist-straps, as well as when not to have the straps looped around your wrist in a potentially dangerous situation, goes a long way in comfort, effort and stability. Used properly, poles can make you feel like a four-legged mountain goat. Used improperly, they're just so much dead weight and a PITA hinderance.
This is a very good point.....technique matters. I see many people with poles, which by their use is obviously only decoration.
How you use the straps, how you hold the handles, how long you have them....all make a big difference in how they work and feel. I've made a lot of adjustments over time.
