Trekking poles will incredibly add to your hiking efficiency if used properly. Reinhold Messner, world famous mountaineer, used them 20 years ago, and he is a climbing animal- he used them to become a mean hiking machine, not because he had any balance problems. I did a few climbs with a fellow from New Zealand and he was like a mountain goat with his poles. He literally could run down a steep rocky slope. So I got some. It took some time to build up my arm strength, but now they add to my uphill walking as well as protect my knees going downhill. I just finished a 3-day trip with two steep 3000+ ft uphill sections and two 3000 foot downhills. Could not have done it without trekking poles! Now if you are just ambling down a flat trail, probably no need for them. It depends on where you hike. Very useful for steep off-trail travel.

For we older backpackers, poles are a godsend. I doubt I would still be at this without poles.