In the coffee grinder (helicopter) the extended leg circles in one-arm support. Learn support, swing and trunk control while protecting your shoulder.
What is the coffee grinder and how do I learn it? In the coffee grinder (often also called helicopter) you sit in a deep squat, support yourself with one hand on the floor, and an extended leg circles low under the body — like the crank of a coffee mill. It is one of the basic footwork elements and the bridge to more demanding floor elements.
The honest answer on learning time: with a secure 6-step and good one-arm support you usually need several weeks until the circle runs round. That is practical experience, not a study. Swinging the leg is easy — staying calm on one hand while doing so is the core.
And the core has its price: the support shoulder carries a large share of your weight in this position. In a survey of 97 breakers the shoulder was affected in 60.8% of injuries, and intensive power-move training was statistically linked to shoulder pathology [2]. Among breakers seeking medical help at US competitions the shoulder topped the list at 39% [3].
The coffee grinder is not a power move in the narrow sense, though: it is a practice field for weight on one hand, calm trunk, round leg — exactly what you need later for turtle, swipe and other elements.
Go into a deep squat, one hand firmly on the floor, the free arm stays at the body. Weight rests over hand and standing foot. Milestone: you hold 15 seconds per side calmly without the trunk tipping.
Extend the other leg and guide it low in small half circles under the body without the standing foot hopping. At first just the movement path. Milestone: ten clean half circles per side without the support hand slipping.
Extend to a full circle in slow motion. The standing foot may hop slightly to let the circling leg pass — the weight still stays calm. The circling leg should almost brush the floor, not strike it. Milestone: five full circles in a row, round and without stopping.
Dance it on the count, then switch to the other side. Build the coffee grinder into a phrase: go-down, 3-step, coffee grinder, back to toprock. Milestone: you dance a 16-count phrase with two circles on both sides on time.
In a small study of eight experienced female breakers the asymmetry of the shoulder internal rotators averaged 14%; the ratio of external to internal rotators was about 38% on the right and 32.5% on the left, and it was linked to the number of strength-training hours per week [1]. This is only a hint study (n = 8) but fits practice: strengthen the rotator cuff in a targeted way, do not just warm up.
Breakers with professional experience train on average about 24 hours a week, and the knee is the most frequently injured site [4]. As a beginner your load is a fraction of that, but you should build technique and strength early. Stop at sharp shoulder or wrist pain and have it checked. This guide does not replace supervised training.
Do not let the free hand hang. When the free arm swings up or to the side, it helps the trunk let the leg pass — and the move immediately looks more like dance. Practise this first with the circle in slow motion, then at tempo. That turns a leg trick into a whole-body move.
With a secure 6-step and good one-arm support many expect a few weeks of regular practice until the circle runs round. That is practical experience, not a study. A calm support arm matters, not tempo.
This catalogue lists both names for the same basic move. How exactly the scene distinguishes the terms varies between crews and teachers. What matters is the principle: one-arm support, low leg circling.
It should not hurt. The support shoulder carries a lot of weight, and the shoulder was affected in 60.8% of breakers in one survey [2]. Pain means: pause, check technique, build strength.
Usually the squat is too high or the circling leg too far from the floor. Go lower, keep the leg flat and make the circle smaller at first. The standing leg needs only a minimal hop for the leg to pass — whoever jumps hard loses the support. That is practical experience, not a study.
There is no reliable study on that. As a practical rule: better short and focused, with breaks. In one survey injury rate was linked to total training time [5].
The Turtle as a Power Move: Rotating in the Arm Balance