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What Muscles Work In A High Kick, And Why The Standing Leg Does As Much As The One That Moves
From the FASTER syllabus: this article is taught in full in The honest route from scratch to qualified →
In short: A high kick splits into two jobs at once. The kicking leg's hip flexors and quads lengthen then drive the leg up and out into the target, the visible half of the movement. The standing leg does the half nobody watches: the glutes, especially glute medius, hold the pelvis level while the whole bodyweight balances on one foot, and the calf and the muscles of the foot grip the ground to stop that foot rolling. The deep core and obliques support both jobs together, resisting the rotation the kicking leg and swinging arms put through the trunk and controlling the leg back down afterwards rather than letting it drop. The four steps that produce that answer are: decide where the force is acting, find the muscles working directly against it (the ones lengthening are easiest to see), find the secondary muscles assisting, then find the muscles supporting the joint. The same four steps already answered the same question about a squat, a lunge, a deadlift, a press-up, a row, a shoulder press, a loaded carry, a suspended plank, a sprint, a medicine ball throw, a vertical jump, a kettlebell swing, a band wood chop, a bird dog, a single-leg overhead reach, a hip hinge, a lateral lunge, a lateral shuffle, a split squat, a single-leg deadlift, a bear crawl, a beast position and a walking lunge.
What muscles work in a high kick
Split it into the leg that moves and the leg that doesn't, because they're doing two different jobs. The kicking leg's hip flexors pull the thigh up and the quads extend the knee out into the target, lengthening then firing through the whole arc. The standing leg's glutes, especially glute medius, hold the pelvis level while the entire bodyweight balances on one foot with nothing else to lean on.
The one people assume they already know
Somebody weighing up a career change into personal training has probably watched a kick land a hundred times, in a class, on a bag, on a screen, and filed the whole thing under "leg movement" without ever separating the leg that travels from the leg left holding everything else up. One of the things you learn on our CIMSPA-recognised personal training course is a method that pulls those two jobs apart and gets specific about what each one is actually doing. The course teaches it in the browser too, so it can be watched, read or answered by dictating the answer back, whichever fits the hour you have.
Twenty-four exercises in, and the method still hasn't changed
A squat, a lunge, a deadlift, a press-up, a row, a shoulder press, a loaded carry, a suspended plank, a sprint, a medicine ball throw, a vertical jump, a kettlebell swing, a band wood chop, a bird dog, a single-leg overhead reach, a hip hinge, a lateral lunge, a lateral shuffle, a split squat, a single-leg deadlift, a bear crawl, a beast position and a walking lunge have all run through the same four steps:
- Decide where the force is acting on the body
- Identify which muscles work directly against that force (muscles that lengthen are easiest to see)
- Identify which secondary muscles assist that movement
- Identify which muscles would support that joint / movement
Run it on a high kick.
One, where is the force acting? At the hip and knee of the kicking leg as it swings up and extends into the target, and at the hip of the standing leg, which is carrying the whole bodyweight alone for the length of the kick.
Two, what works directly against it? The kicking leg's hip flexors lengthen then shorten to lift the thigh, and the quads lengthen then extend the knee out into the target, the two muscle groups doing the visible part of the movement.
Three, what assists? The standing leg's glute medius, working hard to stop the hips dropping toward the unsupported side while the other leg is in the air, and the adductors and obliques on the kicking side, helping rotate the hip through the arc.
Four, what supports? The deep core and obliques, resisting the rotation the kick and the swinging arms put through the trunk, and the standing foot and calf, gripping the ground to keep that one point of contact stable through the whole movement.
Why the fourth answer changes how it's coached
A trainer who only watches the leg that moves has half the picture. A trainer who's run the four steps knows a kick that wobbles on the way up is just as likely to be the standing leg's glute medius losing the fight to hold the pelvis level as it is anything the kicking leg is doing wrong, which is a completely different thing to work on.
Point it at anything
A kick thrown off a shorter standing base, where the glute medius has less foot to balance over. A kick thrown after a sprint, where the standing leg is decelerating the whole body's forward momentum at the same moment it's expected to hold it steady sideways. Any movement that puts the full bodyweight on one leg while the other one does something else can be answered the same way, without a new list to learn.
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Also worth a look: Level 3 Personal Trainer — the anatomy unit this comes from.
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Frequently asked
Why does the standing leg matter more than the kicking leg?
Because it's holding the entire bodyweight on one foot for the whole movement. The kicking leg gets all the attention because it's the part that travels, but the standing leg's glutes are doing an isometric job the whole time it's up.
Is a high kick just a sport skill, not something a personal trainer needs to read?
The method doesn't care whether the movement is a gym exercise or something happening in a sport, activity or class — a trainer who can read one can read the other.
Does finishing the course get me PT Manager?
Yes. PT Manager opens the moment you sign up with FASTER, and adding real clients unlocks once you pass a course.
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