Maco Yoshioka is the founder of Madre Bonita, a nonprofit group that offers postpartum fitness programs for women using elastic exercise balls. Yoshioka, 40, who studied sports physiology at the University of Tokyo, says she became aware of physical and mental difficulties for new mothers when, in the late 1990s, she herself became a single mom at age 25, experiencing many discomforts, such as exhaustion, lack of stamina and sore joints. She stresses the importance of care for women in this period, to help them ward off postpartum depression and stop them from becoming abusive toward their children. Madre Bonita classes are now being taught at 50 locations across the country by 24 accredited instructors, including Yoshioka.