Notes from Wikiquote
Similar expressions were also used in his famous "Speech to the Third Army" in June 1944. The phrase is similar to one attributed to Erwin Rommel, "Sweat saves blood, blood saves lives, and brains saves both", and to an even older one by August Willich: "A drop of sweat on the drill ground will save many drops of blood on the battlefield" from The Army: Standing Army or National Army? (1866)