The alzapua flamenco guitar technique is hardly ever played in any other guitar music. Since it is played by rapid, repeating rhythmic patterns of three different thumb strokes, creating a unique flamenco guitar sound, it is difficult to understand the sequence of strokes.
The Spanish word ‘púa’ means plectrum and ‘alzar’ means lift up and raise. The alzapua flamenco guitar technique originates from the ancient past. Similar techniques have already been used in ancient music composed for the Islamic 'ud. At the beginning of the 19th century, when the flamenco guitar was added to flamenco singing and dance, flamenco guitarists played single note melodies only using the thumb like a plectrum, not involving any fingers. This particular use of the thumb in early flamenco guitar music evolved in a wide range of thumb techniques, demonstrating the skills of a flamenco guitar virtuoso.
To ensure a proper execution of the alzapua flamenco guitar technique, one first has to perfect the thumb rest stroke, also called apoyando. To play a thumb rest stroke, as a part of the alzapua, imagine to hold a ping-pong ball in your right hand palm with the thumb pointing outwards. Place you hand close to the guitar bridge, a bit further than half way between the guitar soundhole and the bridge. Rest your thumb slightly on the 6th string and pluck the 6th string with the thumb at an angle of about 60 degrees. Always pluck the string with your nail and flesh, never only with the nail. The fingers remain curved and the thumb will come to rest on the next 5th string. Movement is generated from the wrist, not bending the thumb at all. Once the thumb rest stroke is mastered, the alzapua flamenco guitar technique can be learned. There are several types of alzapuas across two, three or four strings at different starting points, but most often, the alzapua is played across three strings, for example the 6th, 5th and 4th string. First place the fingers i-m-a on the 1th string to fix the right hand. Next place your thumb on the 5th string, play a downstroke across the 5th and 4th string, followed by an upstroke with the back of the nail across the 5th and 4th string, ending with a rest stroke on the 6th string. This brings the thumb back in its initial position, resting on the 5th string, ready to repeat this cycle of movements.