Speedsters are an odd lot. Their powers are misunderstood and sometimes controversial. To set the record straight, I've asked veteran villain speedster Hurricane Hal to talk about this. I've done some editing of the text, with his permission.
Hey all, Hal here. Mr. Big and I go back a few years and I was very flattered to be asked to talk about what I do. And what I do is run! Let's talk about speedsters:
We don't think radically faster than most people. Super-speed isn't time acceleration. Instead, we're moving our bodies faster. This is a combination of force control, muscular adaptions to moving very fast, and alterations to the nervous system. Our subconscious minds do process motion at super-speeds, but there's plenty of evidence that it happens thanks to the myelin substitutes you'll find in speedsters' brains rather than some kind of time-related power.
We don't perceive things at higher rates. Let me see if I can describe what it's like. When you fire a gun, you take aim, you track your target, but the bullet is off and doing its own thing the moment you pull that trigger. Now instead of a gun, imagine that the bullet is your body. You aim your mind at an objective by focusing on what you want, where you plan to move, whatever, and you commit to it. There's a brief moment of disorientation and it's done. Sometimes the subconscious will do its own thing - speedsters can and have dodged bullets without thinking about it, for example. But we notice all these things after the fact.
We don't send up huge currents of air around us - though we can. Most speedsters have a limited amount of control over the air surrounding their bodies, enough to keep us from being burned alive by friction. We create a slipstream effect that puts the air back where it was once we've gone past. Skilled speedsters learn to use this control to guide the slipstream laterally and create a huge gust of wind as we go by.
We don't age quicker or eat more. Some speedsters might develop a large appetite, but research shows that it's mostly psychosomatic. Their bodies feel the calorie burn and produce feelings of hunger. As we get more used to our powers, those cravings fade. A lot of speedsters I know don't even eat food except as a hobby - our bodies metabolize something else.
Obstacles in our path can still kill us. Someone asked me if I could run through walls. I said yeah - if I wanted to die! You've still built up a tremendous amount of momentum and delivering it to a solid object will very definitely hurt. That said, the slipstream will divert things like water vapor, so I don't die if I run through a rainstorm. If it would hurt you to run through something, it'll hurt a lot more to run through it faster, plain and simple!
Super-speed punches don't work like you think. Speedster fans like speculating about a super-fast person who could run up to a target and punch them, claiming that the momentum will do a lot more damage. Yeah - that works! Unfortunately the damage goes both ways. Newton's Third Law of Motion still works, and you'll break your arm. So let me tell you the secret to super-punches.
Linear momentum is a vector quantity, calculated as p = mv. That's mass times velocity. For example, say that you (a burly 100 kg) sprint (5 meters per second, or about 11 mph) at me and punch me. Your momentum is 100 * 5, or 500 kg m/s. The dominant factor is your mass, no duh. Big men have been kicking sand in the face of the macs at the beach for millennia, everyone knows this.
But instead of punching me with your fist, say that you're a speedster using your slipstream control to punch me with air. You push the air forward just before you connect. The mass of a cubic foot of air is about 0.03 kg, which at the above speeds is negligible - 0.03 * 5 is 0.15, orders of magnitude less. It's a breeze. But you're not moving at that speed, and you're not just moving air normally. I can reach Mach 10 with a good punch, and the slipstream effect is another order of magnitude in effectiveness. That makes my momentum calculation to be 0.03 * 34000, or 1020 - twice the punching power of our typical man at a sprint! And I can do that several times a second. Yes, I can tear through rock and steel without too much effort if I want to. And by the way, the slipstream works on water too, which is a lot heavier than air.
My advice to people interested in fighting hand-to-hand as speedsters is "don't" - there's far more effective uses of your power in combat. But if this is your thing - and it is incredibly flashy and intimidating if you can do it - then I strongly suggest learning a martial art that focuses on fast strikes, so you can build up the necessary muscle memory to do it at super-speed. American Kenpo, Kajukenbo, and Baguazhang all teach fast hand strikes. Wing Chun is a great style, because of its fast strikes, but also because the style works with relaxed muscles and that's how speedsters operate.
Mr. Big here again. Thanks for the contribution, Hal!