When I started riding my trike, I wore Merrell Barefoot Pace Glove shoes. Love these shoes! If I could have ridden truly barefoot, I would have, but these super-light, extremely comfortable shoes were the next best thing.

I loved being able to feel the pedals, and these were terrific shoes until I started riding 20 miles at a time. Around that time, I met an opinionated cyclist, and she told me that I needed proper cycling shoes. With clips.
Yikes! Clips made me think of cages — the metal toe-grabbers that serious cyclists use (used?). I’d always thought of them as the stuff of nightmares — and broken ankles.
It turns out that modern clips are a whole different story. First of all, if you attach your shoes to your pedals, that’s called riding “clipless”. Go figure. Apparently that’s because the steel cages I feared in my youth are called “toe clips”.
The guys at the bike shop told me that I could expect cycling to be about 15% easier if I “went clipless”. Fifteen per cent is a lot, in my book. I’ve mentioned that my trike is more than half my weight, so I work a little harder than most cyclists to get where I’m going.
One of the guys claimed that another benefit is that, with a clipless setup, my calves would be doing more work. Without them, my peddling is mostly driven by my thighs.
I took the plunge. First came the shoes; all I cared about was having enough room in the toe box, because I’ve never abused my feet, and wasn’t willing to start now. The business part is on the sole, though:
That cleat is screwed into the shoe, just behind the toes. It’s metal, but ever-so-slightly recessed into the sole. I wouldn’t walk on wood floors in them, but they shouldn’t cause much damage to most surfaces, since they’re somewhat protected by the vinyl (? I know it’s not rubber) rim around the shoes.
Then came the pedals. My opinionated informant said that mountain bike pedals, with SPD clips (cliplesses?), would be best for me. The fellow who helped me when I choose my shoes seconded this advice, and recommended that I get a pedal with the SPD binding on one side, and a flat surface on the other. That’s the binding side, above, that connects to the clip on the shoe.
Here’s the flat side. On this particular pedal it’s pretty broad; the guy at the shop pointed out that having this pedal meant that I could still ride my trike, even if I’d taken it hundreds of miles from home, and failed to pack my SPD shoes. Gulp.

That was one easy sale.
So how do I like them? They’re amazing — well, maybe the most amazing thing is that a novice like me could feel the difference immediately.
Whatever little lift the clips offer the pedal on the upstroke is just enough to make it much easier for me to make it up a bunch of inclines, without pedal-assist, that I couldn’t quite do on my own, previously. My legs seem more capable, and (as promised) it feels as if I’m using calf and thigh equally. It feels good to use those calves. My feet had never really gotten sore on the long rides, but they definitely knew where they’d been. The stiffer cycling shoes, though, are very, very easy on the tootsies.
Here’s a look at the underside of an SPD pedal. Unlike mine, this pedal has a binding on each side of the pedal. That, presumably, is because the cyclist, writing, as he is, on MtnBikeRiders, is quite a bit more hardcore than moi. (The reviewer didn’t like this cool-looking shoe very much — follow the link to read his comments — so let this be a lesson: All cycling shoes are not the same; buy the shoe that works for you.)

Any drawbacks? Well, an unexpected change. I tend to use the battery more than I did BC (Before Clipsless). Why? Because I have to take my right foot out of the clip to turn the battery on and off. I’m not really adept at that yet, though I expect I will get very good at it over time.
For now, though, it’s easier to leave the battery on if I know I may need it in the next few minutes. Formerly, I turned it off every single instant I could. I actually don’t like using the battery, so I’m hoping this changes fast, but it’s a minor issue compared to all the good things the shoes do.
Oh, and the break-your-ankle factor? Technically speaking, you could get stuck in the pedal and go down. Apparently this is a real risk for bicyclists, but that would be virtually impossible on a tricycle. You release the shoes by twisting your heel to the side — kind of the motion you’d make if you wanted to break your ankle. Only you don’t break your ankle, you just release the cleat and binding.
Shimano warns bicycle riders to detach shoes when slowing and before coming to a stop; that’s a habit that’s worth practicing until it’s second nature (just as you’d want to make the process of clipping and unclipping into an almost unconscious act), but a trike rider is unlikely to get into that kind of trouble, as a tricycle stays upright when stopped.