[2] In the 1920s she again began to hold classes, initially for children in her own home, and by 1926 was training teachers in her own system at the Bagot Stack Health School in Holland Park, London.

This initially involved 12 sequences of exercise designed to train the body in accordance with the seven principles of the Bagot Stack System.

The Women's League of Health and Beauty classes included elements from dance, callisthenics, and remedial, slimming, and rhythmical exercise to music.

[13] Mary Meta (Mollie) Bagot Stack was born 12 June 1883 in Dublin to parents from the Irish Protestant professional class.

[2] She married again on 10 March 1912 to a third cousin, Edward Hugh Bagot Stack (1884 - 1914), a captain in the Gurkha Rifles, who was killed in the First World War.

She travelled with him to India, living in Lansdowne, a hill station near the Himalayas, but returned to the UK at the outbreak of war with her newborn daughter.