Speed climbing is a real sport. In fact, it will be one of three new climbing events in next year’s Olympic Games in Tokyo. The goal is to scale a 15-meter wall and slap a timer button at the top before your opponent in an adjacent lane does. The wall has outcroppings to grab and push off of, and they’re always the same, so competitors have every move memorized.
Still, the speeds they reach are insane—the race looks like a 100-meter dash up a vertical wall. Spider-Man would be jealous! The world record is currently held by an Iranian man named Reza Alipour, aka the Persian Cheetah, with a time of 5.48 seconds. Seriously, check out this video of Alipour at the IFSC World Championships last year.
So you’re thinking, “Hey, it’s early days in this sport. This might be my big chance to make an Olympic team before everyone gets in.” The question you need to answer is this: If you practiced enough—if you mastered the technical skills—do you have what it takes physically to get somewhere close to that speed?
To find out, we want to look at the idea of an athlete’s power output. What is power? In physics, it’s the time rate of energy use. No? OK, let’s refresh.
What Is Power?
Remember how light bulbs used to be rated in watts? Watts are a unit of power. A 100-watt bulb drew energy at a higher rate than a 60-watt bulb, so it was brighter. If you ran them both for an hour, the 100-watt bulb would use up more energy. (In fact, they’d use 100 watt-hours and 60 watt-hours of energy, respectively.)
It’s the same if you hoist a barbell off the floor. There is a decrease in the energy stored in your body, while the barbell increases in kinetic energy (because it speeds up) and gravitational potential energy (because it moves up). To execute the lift fast, you need a high power output. If you take a long time, you’ll have the same transfer of energy but a much lower power level.
You get the idea: In speed climbing, you’re competing on time, so the limiting factor on your performance is your power output—the time rate of energy use. Only here you’re both the motor and the object being moved: You’re using your muscles to hoist your body mass up a wall, in defiance of gravity, which would like you to stay on the ground.
Power Output of a Speed Climber
So what kind of power levels are we talking about? We can estimate it from the video above of Alipour’s climb. All we need to know is the time to the top of the wall and the amount of energy used over that interval. Here’s our basic equation. Power (P ) equals the change in energy (?E) divided by the change in time (?t):
Illustration: Rhett Allain
social experiment by Livio Acerbo #greengroundit #wired https://www.wired.com/story/power-demands-of-speed-climbing