Characteristics of the participants and the time required for portyanki

Trench foot is a nonfreezing cold injury that occurs when the feet are exposed to a cold and wet environment for an extended period. To prevent trench foot, it is important to change wet socks and keep the feet dry. However, securing a large number of socks during natural disasters is challenging. We considered that the footwrap method known as portyanki, used by the Russian military, would be a simple and useful technique to prevent trench foot during natural disasters. To measure the time needed to learn portyanki, we conducted a study with 10 junior resident volunteers. Using a 40 × 70 cm cotton cloth, participants stood with one foot on a cloth set on a 45 cm high table. The researcher gave direct instructions on the portyanki technique. Participants then performed portyanki 10 times consecutively, with the duration of each attempt recorded. The timing started when the foot was placed on the cloth and ended when the edge of the cloth was secured. Each participant completed the experiment individually.