BYDGOSZCZ, Poland — The United States swept the relay races at the World Junior Championships by successfully defending the men's and women's 1,600-meter titles today.

A day after capturing gold in the 400 relays, the Americans held onto the 1,600 titles they won two years ago in Beijing at the last junior worlds.

Marcus Boyd, Bryan Miller, O'Neal Wilder and Jeshua Anderson won the men's event in 3 minutes, 3.86 seconds. Britain finished second (3:05.82) and Germany was third (3:06.47).

In the women's race, Lanie Whittaker, Jessica Beard, Erica Alexander and Takecia Jameson won the gold in 3:30.19 seconds, easily outpacing Ukraine (3:34.20) and Australia (3:34.23).

The U.S. also got a silver medal from Booker Nunley in the men's 110 hurdles on the last day of the meet, which began Tuesday and featured athletes from 183 countries.

Jordan Hasay, who delayed her trip to the meet after reaching the 1,500 finals at the U.S. Olympic trials, finished fourth in that event.

In the final medal count, the United States topped the standings with 17 medals, including 11 gold. Germany had 10 with six gold and Kenya had 11 with four gold.