Front kick
Mae geri, the front kick, is the most commonly-used kick, because simple, straightforward kicks tend to be the most effective. Spinning kicks are intrinsically telegraphing, with complex setups that force you to turn your back on your opponent. Jump kicks leave you vulnerable while jumping and landing. Drop kicks sacrifice your balance. Simple linear kicks have none of these problems.
Front kicks are a four point process. Slowly practice each step individually, then put them all together. Speed is for rabbits and fools. Instead, concentrate on executing a proper form, and worry about performing that as smoothly and fluid as possible. Remember, slow is smooth, and smooth is fast. The four points are:
- Chambering. Enter a walking crane stance, raising your knee as high as possible. Ideally, knee your chest. At minimum, your knee must be “past parallel” -- your knee must be higher than your hips, so that your thigh is angled upward with respect to the floor.
Remember to slightly-bend your supporting leg, keeping your knee directly over the toes to improve your balance. Pretend that your spine and supporting leg is a telephone pole buried deep in the ground. This sturdy grounding keep you from being blown back from the recoil of your kicks.
Keep your arms close to your chest to shield yourself. As long as you remain on one foot, your defense is compromised -- your blocks will be weak (since you cannot drive with your legs), and evasive footwork requires two feet. - Kicking. Push the knee down and forward to drive your foot horizontally into the target. The most common problem with kicks is flicking them, instead of snapping them. A “flicky” kick swings your foot up from a fixed knee, as though your physician were checking your reflexes. A proper front kick “drives with the knee” ; the knee lowers, and the foot travels horizontally with no arc, like a scissors jack. Test your front kicks by using them to close car doors or crumple cardboard boxes. A flicking kick just wipes the dirt off the door or box.
[video of flicky and proper front kicks from the front and side, and their effects on car doors.]
Be careful, as flicky kicks may feel like good form. To keep yourself honest, practice against a responsive target, like a hanging heavy bag. A proper front kick will dent a heavy bag. Heavy bags remain stationary when flicked, and swing when pushed by kicks with poor snap. Since heavy bags are round, kicks which aren’t perfectly straight-in will glance off.
In Goshin-Jutsu, front kicks contact their targets with the ball of the foot. Some karate styles, like Uechi-ryū, impact with the tip of the big toe for a more piercing kick. Since "toe-kicks" can lead to jammed and broken toes, they are only acceptable when you are wearing steel-toed work boots. Some other arts, like Tae Kwon Do, perform flicking front kicks which impact with the instep, even though the instep is one of the weak points of the human body.
To help keep your balance, do stomach crunch to tense your abdominal muscles as the kick extends. This keeps your shoulders directly over your hips, which is the secret to stability. Some karate styles, like Shōtōkan, advocate leaning back as you kick, to balance yourself by using your torso as a counterweight. However, leaning back means having to lean forward later, and this extra motion results in slower techniques and wasted energy. - Re-chambering. Return to walking crane stance as quickly as possible. As a rule, kicks should return twice as fast as they went out. Resist the urge to use your kick as a giant step. By immediately returning to the chambered position after kicking, you have the option of throwing additional kicks.
- Stepping out. When you are done kicking, set your kicking leg behind you, and enter a front stance or fighting stance. Alternately, you can slide your kicking foot down beside your support foot (in a sort of bent-knees attention stance) and then slide your kicking foot out into a front or fighting stance. What you will not do -- ever, for any reason -- is to step forward directly from crane stance into some other stance. Using kicks as a giant steps transfers your weight to a leg which isn’t touching the ground, setting your opponents up to topple you instantly with a well-timed leg sweep.
Putting it all together, a front kick looks like this:
[video of a front snap-kick, viewed from the front and side, many times, fast and slow.]
This is a lot to take in, but we must be thorough. Slowly practice each step individually, and then put them all together. Emphasizing speed over form wont make you a better martial artist; it just makes you suck faster.