I started using trekking poles a few years ago and see the benefit. They are really good at reducing the shock on your knees and lower extremities. If your knees are weak our your fitting pain with age the trekking can be your friend. However, if your young and in good shape you may not need them or want them. I find they are good for support when climbing up hill or in rocky situations. Overall, they have a place on the trail and are more for the mature hiker that has some miles under their belt so to speak. My knees have thanked me time and time again. Nice topic to bring up and looking forward to hearing others feedback.

I probably wouldn't ever hike more than 3 miles without poles anymore. When you first start using them, it feels weird, I admit. But gradually they become an extension of your body helping you to move faster and go farther. I can move faster with poles and hike more efficiently - bottom line.

One thing that no one has mentioned yet is that when you're hiking without poles, you're legs are literally doing all the work while your arms just dangle there. Your arms aren't getting proper blood flow, can swell and get cramps. When I'm hiking without poles, I sometimes find myself opening and closing my hands a lot to get the blood moving. Hiking with poles is a full-body, cardio experience.

Other reasons I use poles:

Move faster -- don't have to stare at the trail as much to watch for rocks. I use the poles to guide my movements, swerving around obstacles and catching myself if I start to trip. I also use them to feel for rocks so I know how high to lift my leg sometimes.
Safety -- If you have a 35-50 lbs pack on your back and you're moving fast, trip, and go down, a fall on your wrists can take you off the trail. Poles will catch you.
Animal safety - if I surprise an animal on the trail or some viscous dog comes tearing at me I want to have a pole in my hand.
Ease on joints - going down more than up, but really it's like doing the trail with hand rails. It's almost like cheating.
Tent/Tarp support - obvious, if needed.
Move stuff -- I clear cobwebs, sticker bushes, poison ivy out of the way before I step through. If it's at night, sometimes I lift the pole to catch webs that I may walk through.
Injury support - got something to lean on if I twist an ankle

There are so many reasons to use poles that it seems silly for someone to not get them, especially the compact folding Z-poles that BD makes. They are so light that they literally take up no space at all. If you get a chance to borrow someone's poles, I'd encourage you to try them out. They are more than useful.

Last year I went on a day hike. The side of the hill gave way & pitched me into a ravine & it was about 30 min befor I could put weight on my right leg. If I had a trekking pole could have used it like a crutch so now I never hike with out one( plus love the extra support for my knees)

I always take them no matter what. Great for creek crossings, loose rocks on the trail, stepping up on big boulders with heavy pack, coming down steep inclines really saves my knees, and keeping my balance in heavy snow or icy trails.

Thanks for all the input!

I've used poles (tried them for a month) before and it just seemed like they always got in the way. I did a ~100 mile backpacking trip without poles and felt just fine plus numerous other trips. I've been hiking since I was a young little cub scout and have never stopped. So maybe it's just an old habit that I never grew out of.

I've used a walking stick before but very rarely. I already hike pretty fast, I usually end up waiting on people. It seemed like poles slowed me down.

I'm with you. I've always viewed them as something else to carry. However, there will come a day I'll want them, but that day is not now.