Counting the breaths (usually up, not down) is the standard starting practice in zazen, Zen meditation. When you lose track you bring your mind back to counting

Counting the breaths (usually up, not down) is the standard starting practice in zazen, Zen meditation. When you lose track you bring your mind back to counting again at 1, so it's more like "1.. 2.. shit. 1.. ugh. 1.. 2.. 3.." than anything actually involving 10.