To hike some mountain trails, or to travel along a canyon strewn with boulders, one needs to be sure-footed. But what exactly contributes towards sure-footedness?
Firstly, the hiker needs to have good balance. Without that, it’s impossible to traverse difficult country at speed. It’s also necessary to have good vision, particularly the ability to judge the distance to your next footstep.
Next, there’s a need for good muscle strength and muscle control. With these, you can reliably reach the next good footing.
You need to understand the physics of each footstep. Will the tiny stones under your next footstep roll like ball bearings, or will they dig into the earth that they are resting on? That boulder you are about to step onto—will it shift when you apply your body weight to one side of it? Where does the water flow when it rains? Those parts may be slippery even after the rain has passed.
If you understand the physics of a “dynamic” footstep, or have an intuitive “feel” for it, you will be much more secure over slippery terrain. With a dynamic footstep, you don’t attempt to stop on every boulder. Instead, you keep moving, placing your foot in one place (often the peak of the boulder) and pivoting as you pass over so that the force you apply is always pushing through the middle of your foot and towards a direction in which the boulder has stable support. When you make your way across a group of boulders with these dynamic moves, this is called “rock-hopping”.
Fast reflexes are important. If your foot starts to slide, you need to take your weight off that leg quickly, and place your other foot somewhere stable. If that’s not possible, sometimes you can quickly jerk the sliding foot into a more stable position—but only if you can respond before gravity has had much time to act. If you step on a boulder that starts to move, with fast enough reflexes you can push off hard against its inertial mass, so that you can reach your next foothold before the boulder moves too far.
Many people cite “proper footwear” as a prerequisite for sure-footedness, but the best footwear differs enormously according to terrain. A vibram sole holds brilliantly on dry grainy rock, but on wet slick rock a rubber sole can be better. On a slope covered with wet mountain grass, a sole with protrusions works best, but on wet limestone a flatter sole with greater contact area can work better. Even the stock recommendation to wear “stout shoes” is dubious. On irregular and slippery rocks, a softer shoe like the Dunlop Volley lets you curve your foot around a convex part of the rock, greatly increasing your contact area.
Walking poles can increase your stability, provided you don’t lean on them. If you do, and they slip, you’re likely to stumble or fall.
Finally, it’s important to be able to choose the best route across the terrain. Each step must be stable, or at least be a fleeting dynamic footstep on the way to a stable landing. On steep or treacherous ground, you always need to have a backup step in mind, to avoid accident or injury when your footing gives way—which it inevitably will do now and then.
Oh, and having four legs helps for sure-footedness, but most of us can’t do anything about that.
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