Oops, it doesn't look like 'outrigger sprints day' is a national day..

Other days

boy friend

Boy Friend Day
prosecco

Prosecco Day
comfy

Comfy Day
singles

Singles Day
blanket fort

Blanket Fort Day
self care

Self Care Day
believe

Believe Day
hoodie

Hoodie Day
lisp

Lisp Day
mean girls

Mean Girls Day