Power to weight ratio for sprinting is simple: it's how much power you can put into the ground compared to how much body you have to carry. Strength on its own isn't the number that matters for speed. Power and strength relative to your own body weight is. So you can get stronger, get more powerful, and still come out slower if the weight you put on to get there was too much for what you got back.
Watch: the video this post comes from
That's a bad trade. And most players make it without knowing they made it.
Why this is a physics problem
Every kilo you carry, you carry through every single stride. When you're running flat out, your foot is on the ground for around a tenth of a second. That's the only window you get to push yourself forward. Whatever you can put into the ground inside that window has to move all of you.
So if you add size and your power goes up a little, but your weight goes up more, you've got less power for every kilo. You're stronger on paper and slower on the pitch. See?
I don't base the work on theories. I base it on physics and the laws of mechanics. And physics doesn't care what you lift. It cares how much force you produce, how fast, against how much mass.
Power to weight ratio for sprinting vs the number on the bar
This is where players get caught. The lift goes up, so they think they're improving. But your body doesn't know the number on the bar.
Here's how I explain it to our athletes. If you move the same weight faster than last week, that's an improvement. Chasing an extra 10 kg on the bar doesn't mean anything if it doesn't come out in your running. That's ego speaking.
And there isn't one magic ratio either. I can't tell you it's two times body weight, because it's different for every athlete. It comes down to the length of your thigh bone, where your muscles attach, and the levers you've been given. Two players can lift the same weight at the same body weight and get completely different speed out of it.
The joint that has to hold it
There's a second part of the trade most people never look at: the structure underneath.
As an athlete gets stronger, the rest of his body has to be able to take what he's now producing. The ankles are the ones I watch. At contact, the ankle has to hold under that new level of force. If it gives way, the force doesn't transfer into the ground. It leaks.
So now you've got a stronger athlete standing on a joint that can't hold what he's putting through it. More power going in, less coming out. On film you can see it: the ankle collapses on contact instead of staying stiff like a spring.
That's why we keep the ankles strong alongside the gym work, and why we film every rep. You can't feel that leak. You have to see it.
Big doesn't have to mean slow
None of this means you have to be small to be fast. Look at the Haalands of the game. Still quick at a large size. They carry all that strength and they've kept the rotation and rhythm through the top half of the body.
What kills the big athlete's speed isn't the size. It's weight that didn't bring enough power with it, a joint that can't hold the force, and so much bracing that he can't move with any rhythm. Fix those, and size stops being a problem. I go through the tension side of this in does squatting make you faster.
How to check your own ratio
You don't need a lab. You need to measure power against your weight over time, and watch which way it moves.
- ✓Track your bound distance next to your body weight and your lift. The 10-bound test: a 5 m run-in, then 10 continuous bounds, measure the distance. If your weight and your lift go up and the bound stays flat, the trade went the wrong way.
- ✓Time your sprints. If you've put on size and your first 10 m and top speed in km/h haven't moved, the extra weight isn't paying for itself.
- ✓Film your contacts. Watch the ankle when the foot hits. If it sinks, the structure isn't ready for the strength.
Right? The goal isn't to be the strongest player in the gym. It's to get there first.
Our assessment measures all of this against your body, so you know whether your next block should add strength, add power, or protect what you've got.