Use ankle weights to build kick speed by performing straight-leg stretch kicks with the weights on, then immediately repeating the drill without them. The contrast is the whole point. Your legs feel weightless, your range of motion opens up, and your kicks fire faster than they ever have.
That's it. That's the drill.
Kru Robert Perez uses it with his fighters in the Muay Thai Bible, and he compares it directly to what boxers do with weighted gloves or two- and three-pound dumbbells for hand speed. Same principle, different limb. Load the movement, then unload it. Your nervous system over-corrects and the unweighted version feels like it's moving by itself.
Here's how to run it:
Start in a front fighting stance. Lift your lead leg in a perfectly straight line — no knee chamber, no hip hitch, no cheating. Just a straight lift. Kru Perez is blunt about it: he doesn't care how high you get the leg when you're starting out. Four inches is fine. What matters is that the leg is straight and the hip is opening.
Ten reps each side. Switch legs. Ten more. Keep the tempo controlled — this is a mobility and speed drill, not a cardio flush.
The reason this works is all about hip pathways. Kicking power doesn't come from the leg. It comes from the hips unlocking, and flexible hips give that power somewhere to go. The ankle weight forces the stabilizers to work harder while you groove the movement pattern. Take the weight off and you've got mobility plus explosiveness stacked on top of each other.
One caution. Don't throw full-power roundhouses with ankle weights on. The drill above is a slow, controlled stretch kick — that's the safe application. Ripping snap kicks at full speed with extra weight on your ankle is how knees blow up.
Light weights. Straight legs. Controlled tempo. Then drop them and feel the difference.
For the complete kick development system, check out our guide to developing kicking power in Muay Thai and our full roundhouse kick breakdown. Get the whole course in the Ultimate Muay Thai Training System.