By David Gold

Michael Phelps_9_AugustAugust 9 - Michael Phelps leads the United States Sports Academy nominees for July's athlete of the month award after making history at the Olympics.

The American swim sensation (pictured top) picked up a record 19th medal at the Games during July, claiming silver in the 200 metres butterfly and then gold in the 4x200m relay.

With 15 gold and 19 medals in total, that made Phelps the most successful Olympian of all time, overtaking Soviet gymnast Larisa Latynina.

Since his record-breaking heroics at the end of July, Phelps continued in stunning form as he won a further two gold medals, becoming the first man to defend three successive Olympic titles in two disciplines.

He faces competition for the men's award from Swiss tennis ace Roger Federer, who equalled Pete Sampras' record of seven Wimbledon titles when he beat home favourite Andy Murray last month 4-6, 7-5, 6-3, 6-4.

It was his first Grand Slam title in over two years and his 17th major title in total, and the result moved him up to the top of the ATP world rankings again.

That also meant he broke the record for the most weeks in the number one slot.

South African golfer Ernie Els won The Open in Britain by one stroke in July, to clinch his fourth Major championship.

Jimmie Johnson_9_AugustMotor-racing ace Jimmie Johnson performs a celebratory donut after winning the Brickyard 400

Also in the running is NASCAR racer Jimmie Johnson; the American won his fourth Brickyard 400, destroying the rest of the field as he led 99 of 160 laps.

It meant he joined an exclusive club of four drivers who have four times at the Indianapolis Motor Speedway in the Indy 500 Series.

The other two men's contenders both enjoyed superb Olympic Games.

South Africa's Cameron van der Burgh broke the 100m breaststroke world record to beat Japan's Kosuke Kitajima, a quadruple Olympic champion, to gold.

Bradley Wiggins will also be a strong contender for the prize after he became the first British winner of cycling's Tour de France, after 75 years.

Wiggins followed that up with an Olympic gold in the time trial at the start of August.

Leading the running for the women's award is American tennis star Serena Williams.

She enjoyed a superb month as she claimed her fifth Wimbledon title and 14th Grand Slam victory in all.

Williams went on to win the Wimbledon doubles title with sister Venus, and carried on her form into August by winning the women's Olympic singles gold medal.

Kazakhstan's weightlifter Zulfiya Chinshanlo broke a clean and jerk world record at the Olympics, claiming gold in the women's 53kg category.

Two American swimmers, Dana Vollmer and Missy Franklin, are also in contention for the crown.

Vollmer set a world record as she won the 100m butterfly title at London 2012.

Zulfiya Chinshanlo_9_AugustGold-winning weightlifter Zulfiya Chinshanlo broke a clean and jerk world record at the Olympics

The 24-year-old has a heart condition which means a defibrillator has to be kept poolside, but powered to victory to claim the Olympic title, having missed out on Beijing 2008.

Franklin, just 17, beat Australia's Emily Seebohm in the 100m backstroke to claim a dramatic Olympic gold medal, setting an American record in the process.

Completing the contenders are South Korean golfer Na Yeon Choi, and American skeet shooter Kimberly Rhode.

Choi won the US Women's Open by four shots - her first Major championship win - finishing seven under par for the tournament.

Rhode set American Olympic history last month when she claimed gold in the women's skeet.

In equalling the world record by missing just one in 100 shots, Rhode became the first American to claim an individual medal at five consecutive Olympics.

She had previously won gold at Atlanta 1996, bronze at Sydney 2000, gold at Athens 2004 and silver in Beijing four years ago.

Members of the public have until next week to vote for the award by clicking here.

The monthly winners of the award go into the running to become the overall male and female World Athletes of the Year.

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