What are the main muscles used in kicking?

[zambri]

The title says it all doesn't it? For any inside kicks would it be your quadriceps and abductors, and for most out sides adductor's as well as hamstrings. I would just like to know.

Thanks=]

[tricker_d]

Your penis. No really, it gives your quads, hip flexors, glutes, and hamstrings magical powers.

[Bryanimay]

Your core muscles come into play when kicking too .

[Skilzat85X]

Think about the individual motions of your muscles.

Your quadriceps extend your leg.
Your hamstring retract your leg.
Your Iliopsoas pulls your thigh upwards (forwards).
Your adductors pull your thigh sideways outward.
Your abductors pull your thigh sideways inwards.
Your gluteus maximus pulls your thigh backwards.
Your calves pull your toes forwards.

So when you say, front kick, your thigh pulls forwards, your leg extends outwards. Iliopsoas + Quads. (not including retraction, anyways)
What about spinning hook kick? Leg picks up into a chamber, Iliopsoas + Hamstring, Leg pulls up about 45 degrees off the target while extending, Glutes + Adductors and Quads, leg pulls backwards across then retracts, Glutes then Hamstrings. Toes point, calves.
I might be a little off but you get the idea.

Generally, in almost any kick used in most kick tricks, your Quads are always used, seeings as you need to kick to full extension. And your Iliopsoas (hip flexors) pull your thigh up, so you'll commonly use it, though not so commonly with say hooks and rounds, but hardly anyone does full on hooks in their tricks, more of hybrids.

And as has been said, core strength does play a role too, though it doesn't have much to do with the actual physical leg motions.

[kickjim]

Some gastrocnemius [calf] info I find usefull & interesting:

The Gastrocnemius is the calf muscle that is visible from the outside of the body. It's attached to the heel with the Achilles Tendon and originates behind the knee on the femur, crossing two joints.

The Gastrocnemius has two heads, medial and lateral. Known too from a diamond shape if fully developed.

The Soleus is not visible when looking at the body from the outside, it's situated underneath the Gastrocnemius on the rear of the lower leg.

The Soleus is most active when doing calf exercises where the knee is bent, such as seated calf raises.

[kickjim]

I find a strong core very beneficial, especially for twisting and tucking motions.

[Skilzat85X]

It should be brought to the attention of the masses that in terms of kicks and tricks in general, power is more important than strength for these things specifically.