Ben Lecomte, a 50-year old Frenchman turned Texan, will slip into the water Sunday off the coast of Choshi, Japan, and start swimming. If all goes as planned, he won’t set foot on land for six months.

Keeping with Japanese tradition, the women’s 100-meter breaststroke offered a tight finish on the second night of the Japan Swim in Tokyo. Clocking a time of 1:06.21, Satomi Suzuki emerged victorious, ...