Asaki Nishikawa, Mio Narita Grab 400 IM Titles at Japan Swim Depth in the men’s 400-meter individual medley has been a leading storyline in Japan in recent months, and Sunday was the turn of Asaki Nishikawa to display his talent in the event. A 19-year-old, Nishikawa posted a time of 4:08.66 to prevail in the 400 IM at the Japan Swim in Tokyo. That performance was more than a second quicker than Raito Numata, who picked up second place in 4:10.29.