LONDON — Standing on the medal podium with gold draped around her neck, Kayla Harrison laughed and cried.
She thought of all the practices when it was difficult to pick herself off the mat. All the 4:30 a.m. wake-up calls for weightlifting sessions. All the moments her coaches at Pedro’s Judo Center in Wakefield, Mass., pushed her to be better. All the times she visualized winning an Olympic title. All that she had overcome.