The United States made up for their botched performance in the sprint relays by winning both 4x400 meters events on Saturday to finish the Olympic athletics program on a high.

LaShawn Merritt, Angelo Taylor, David Neville and Jeremy Wariner clocked a combined time of two minutes 55.39 seconds to win the men's gold medal while Mary Wineberg, Allyson Felix, Monique Henderson and Sanya Richards won the women's gold in 3:18.54.

The two victories enabled the United States to overtake Jamaica and Russia [Images] at the top of the athletics' medals tables with seven golds and just the men's marathon to come on Sunday.

"To end it with an Olympic record after everything they'd gone through, that shows you that they care about representing America," U.S. men's head coach Bubba Thornton said.

The United States failed to make either final of the 4x100 relays, after dropping the batons in the heats, but there were no mistakes with the longer relays.

The men were overwhelming favourites to win after fielding the three medallists from the individual 400 final, Merritt, Wariner and Neville as well as the 400 hurdles champion Taylor.

They led at all four changeovers and finished almost three seconds ahead of runners-up Bahamas and third-place Russia.

"We gave it our all and we ran an Olympic record and close to the world record," said Wariner.

"A lot of things happened here that we weren't expecting. That gives us a lot to work on for the world championships next year."

The women's race was a much tighter affair, with Richards surging past her Russian rival Anastasia Kapachinskaya in the last 25 meters to snatch the gold and make amends for her third placing in the individual 400.

"I knew I had to pull out a supreme effort to help our team win and I'm happy we were able to do that. I came to the Olympics [Images] to win a gold medal," Richards said.

Russia, who led at the last handover, took the silver while Jamaica won the bronze as the United States, who abandoned their traditional blue vests for a red outfit, silenced their critics by finishing top of the athletics medals.

"We wanted to come out with the new uniform, a new fresh attitude and fresh outlook and go out there and prove our point, that it's not over yet," Henderson said.

"We've been overshadowed by the wonderful performance of the Jamaicans, but honestly, we've had a very strong performance this year."