During World War 1 soldiers were ordered to inspect their feet daily; they were also paired up and instructed to observe the feet of their partner (because it was discovered that a soldier was more likely to remove the socks and boots and dry the feet when a fellow soldier was there) to ensure that meticulous foot care was conducted.
After trench foot occurred in thousands of soldiers, the soldiers were all ordered to carry three pairs of socks with them at all times. They were ordered to change and rotate the dry socks at least two times each day. They were also instructed to massage the feet after they were dry with whale oil.
The trenches were kept as dry as possible using wooden boards to keep soldiers from walking in the water; these boards were called duckboards. Exposure to the outdoor elements was limited by the employment of troop rotation. These measures were found to decrease the incidence of trench foot.