Kicking power is largely dependent on how fast you can lift your leg off the ground.
This involves strengthening the hip muscles. Doing squats will help a little but leg lifting and working the hip flexors are a much more efficient way of getting strong kicks FAST!
In order to have really effective kicks you must also train your balance and flexibility. When you are flexible your choice of striking targets increases.
These drills when done on a regular basis will greatly improve your kicks regardless of your martial arts style.
Try doing these drills with ankle weights on as well.
Most of the people in the video are wearing 2 to 5 lbs. Anything heavier will probably slow you down to much.
Come and try out our adult class and see if training like this is for you.