Forearm rotation – free course

Turn a door handle or a key: you are performing a forearm rotation (pronation towards the thumb, supination towards the 5th finger). This movement, often invisible in great pianists, is one of the secrets of effortless technique. It spares the fingers by handing part of the work to much more powerful muscles.

Where rotation is essential

Alberti basses and broken accompaniments (C-G-E-G): the hand rocks like a pendulum between thumb and 5th finger.
Tremolos in octaves or chords.
Arpeggios: rotation helps the hand "turn" around the thumb (see arpeggios).
Weak outer fingers: the 4th and 5th fingers receive help from the forearm.

Exercise 1 — the pendulum

Put the thumb on C and the 5th finger on G (right hand). Without moving the fingers, rock the hand: thumb plays, then 5, then thumb…
The movement should be small and even, like a very slow windscreen wiper. The fingers stay passive: the forearm does the playing.
Gradually speed up towards a tremolo, reducing the amplitude.

Exercise 2 — Alberti bass in the right hand

Play this pattern slowly, exaggerating the rotation at first, then making it almost invisible. The fingerings shown are for the right hand.

M:4/4
L:1/8
Q:1/4=69
K:C
!1!C!5!G!3!E!5!G CGEG | !1!B,!5!G!2!D!5!G B,GDG | !1!C!5!A!3!F!5!A CAFA | !1!C!5!G!3!E!5!G C4 |]

Common mistakes:

Keeping a large rotation at high speed: the faster you go, the smaller the movement.
A locked wrist: rotation needs a supple wrist, otherwise it turns into tension.
Letting the fingers "fall asleep": they stay firm and ready; rotation helps them, it does not replace them.

Tip: in any series of notes, each change of direction between thumb and 5th finger is an opportunity for rotation. Look for them in your pieces: Für Elise is full of them, especially in the left-hand broken chords.